Tag Archives: deep-sea animals

Episode 400: Four no wait Five Mysteries!

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To donate to help victims of Hurricane Helena:

Day One Relief – direct donation link

World Central Kitchen – direct donation link

It’s the big 400th episode! Let’s have a good old-fashioned mystery episode! Thanks to Richard from NC for suggesting two of our animal mysteries today.

Further reading:

A 150-Year-Old Weird Ancient Animal Mystery, Solved

The Enigmatic Cinnamon Bird: A Mythical Tale of Spice and Splendor

First ever photograph of rare bird species New Britain Goshawk

Scientists stumbled onto toothy deep-sea “top predator,” and named it after elite sumo wrestlers

Bryde’s whales produce Biotwang calls, which occur seasonally in long-term acoustic recordings from the central and western Pacific

A stylophoran [drawing by Haplochromis – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=10946202]:

A cinnamon flycatcher, looking adorable [photo by By https://www.flickr.com/photos/neilorlandodiazmartinez/ – https://www.flickr.com/photos/neilorlandodiazmartinez/9728856384, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=30338634]:

The rediscovered New Britain goshawk, and the first photo ever taken of it, by Tom Vieras:

The mystery fish photo:

The yokozuna slickhead fish:

The Biotwang maker, Bryde’s whale:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

We’ve made it to the big episode 400, and also to the end of September. That means monster month is coming up fast! To celebrate our 400th episode and the start of monster month, let’s have a good old-fashioned mysteries episode.

We’ll start with an ancient animal called a stylophoran, which first appears in the fossil record around 500 million years ago. It disappears from the fossil record around 300 million years ago, so it persisted for a long time before going extinct. But until recently, no one knew what the stylophoran looked like when it was alive, and what it could possibly be related to. It was just too weird.

That’s an issue with ancient fossils, especially ones from the Cambrian period. We talked about the Cambrian explosion in episode 69, which was when tiny marine life forms began to evolve into much larger, more elaborate animals as new ecological niches became available. In the fossil record it looks like it happened practically overnight, which is why it’s called the Cambrian explosion, but it took millions of years. Many of the animals that evolved 500 million years ago look very different from all animals alive today, as organisms evolved body plans and appendages that weren’t passed down to descendants.

As for stylophorans, the first fossils were discovered about 150 years ago. They’re tiny animals, only millimeters long, and over 100 species have been identified so far. The body is flattened and shaped sort of like a rectangle, but two of the rectangle’s corners actually extend up into little points, and growing from those two points are what look like two appendages. From the other side of the rectangle, the long flat side, is another appendage that looks like a tail. The tail has plates on it and blunt spikes that stick up, while the other two appendages look like they might be flexible like starfish arms.

Naturally, the first scientists to examine a stylophoran decided the tail was a tail and the flexible appendages were arm-like structures that helped it move around and find food. But half a billion years ago, there were no animals with tails. Tails developed much later, and are mainly a trait of vertebrates.

That led to some scientists questioning whether the stylophoran was an early precursor of vertebrates, or animals with some form of spinal cord. The spikes growing from the top of the tail actually look a little bit like primitive vertebrae, made of calcite plates. That led to the calcichordate hypothesis that suggested stylophorans gave rise to vertebrates.

Then, in 2014, scientists found some exceptionally well preserved stylophoran fossils in the Sahara Desert in Africa. The fossils dated to 478 million years ago and two of them actually had soft tissue preserved as the mineral pyrite. Pyrite is also called fool’s gold because it looks like gold but isn’t, so these were shiny fossils.

When the soft tissue was observed through electron microscopes in the lab, it became clear that the tails weren’t actually tails. Instead, they were more like a starfish arm, with what may be a mouth at the base. The arm was probably the front of the animal, not the back like a tail, and the stylophoran probably used it to grab food and maybe even to crawl around.

Most scientists today agree that stylophorans are related to modern echinoderms like starfish and urchins, but there is one big difference. Echinoderms show radial symmetry, but no stylophoran found so far does. It doesn’t really even show bilateral symmetry, since the two points aren’t really symmetrical to each other. We’re also not sure what the points were for and how such an unusual body plan really worked, so there are still a lot of mysteries left regarding the stylophoran.

Next let’s talk about a mythical bird, called some variation of the word cynomolgus, or just the cinnamon bird. Naturalists from the ancient world wrote about it, including Pliny the Elder and Aristotle, and it appeared in medieval bestiaries. It was said to be from Arabia and to build its nest of cinnamon sticks in the tops of very tall trees or on the sides of cliffs.

Cinnamon comes from the inner bark of cinnamon trees, various species of which are native to southern Asia and Oceania. It’s an evergreen tree that needs a tropical or subtropical climate to thrive, and it smells and tastes really good to humans. You might have seen cinnamon sticks, which are curled-up pieces of dried cinnamon bark, and that’s the same type of cinnamon people used in the olden days. Ground cinnamon is just the powdered bark. Like many other spices, it was highly prized in the olden days and cost a fortune for just a little bit of it. Ancient Egyptians used it as part of the embalming process for mummies, ancient Greeks left it as offerings to the sun god Apollo, ancient Romans burnt it during the funerals of nobility, and it was sought after by kings throughout the world.

One interesting thing is that if you live in the United States, the cinnamon in your kitchen cupboard is probably actually cassia, also called Chinese cinnamon because it’s native to southern China. Cassia is often mentioned alongside cinnamon in old writings, because they’re so similar, but true cinnamon comes from a tree native to Sri Lanka. It’s usually marketed as Ceylon cinnamon and is more expensive, but cassia is actually better for baking. True cinnamon has a more subtle flavor that’s especially good with savory dishes, but it loses a lot of its flavor if you bake with it.

Anyway, back in the olden days, no one outside of subtropical Asia and Oceania knew where cinnamon came from. The traders who bought it from locals to resell definitely weren’t going to tell anyone where it was from. They made up stories that highlighted just how hard cinnamon was to find and harvest, to discourage anyone from trying to find cinnamon on their own and to keep prices really high. As Pliny the Elder pointed out 2,000 years ago, the cinnamon bird was one of those stories.

The cinnamon bird was supposedly the only animal that knew where cinnamon trees grew, and it would peel pieces of the bark off with its beak, then carry them to the Arabian desert or somewhere just as remote, where it would build a nest of the bark. The birds were supposed to be enormous, sometimes so big that their open wings stretched from horizon to horizon. Their nests were equally large, but so hard to reach that no human could hope to climb up and collect the cinnamon. Instead, cinnamon hunters left dead oxen and other big animals near the area where the birds had nests. The birds would swoop down and carry the oxen back to their nests to eat, and the extra weight would cause the nests to fall. In other stories, cinnamon hunters would shoot at the nests with arrows with ropes attached. Once several arrows were lodged into a nest, the hunters would pull the ropes to dislodge the nest and cause it to fall, so they could collect the cinnamon.

Of course none of that is true. Some scholars think the cinnamon bird is probably the same mythical bird as the phoenix, but without any magical abilities. Others agree with Pliny the Elder that it was just a way for traders to raise their prices for cinnamon even more. Either way, the cinnamon bird is probably not a real animal.

There are birds with cinnamon in their name, but that’s just a reference to their coloration. Cinnamon is generally a reddish-brown in color, and in animals that color is often referred to as rufous, chestnut, or cinnamon. For example, the cinnamon flycatcher, which lives in tropical and cloud forests along the Andes Mountains in South America. It’s a tiny round bird, only about 5 inches long including its tail, or 13 cm. It’s dark brown and red-brown in color with black legs and beak, and a bright cinnamon spot on its wings. It eats insects, which you could probably guess from the name.

This is what a cinnamon flycatcher sounds like:

[tiny bird sound]

Next, we need to talk about the New Britain goshawk, which Richard from NC told me about recently. It lives in tropical forests of Papua New Guinea, and is increasingly threatened by habitat loss. In fact, it’s so rare that it was only known from four specimens, and it hadn’t been officially spotted since 1969 and never photographed—until March of 2024.

During a World Wide Fund for Nature expedition, a wildlife photographer named Tom Vierus took lots of pictures of birds. One bird he photographed was a hawk sitting in a tree. He didn’t realize it was a bird that hadn’t been seen by scientists in 55 years, until later when he and his team were going through his photographs.

The goshawk is large, and is gray and white with an orange face and legs. We know very little about the bird, naturally, but now that scientists know it’s alive and well, they can work with the local people to help keep it safe. It’s called the keango or kulingapa in the local languages.

Next, we have a bona fide mystery animal, and a deep-sea mystery animal at that—the best combination!

In 1965, the U.S. Navy teamed up with Westinghouse to build a submersible designed by the famous diver and naturalist Jacques Cousteau. The craft was called Deepstar 4000 and between 1965 and 1972 when it was retired, it conducted hundreds of dives in different parts of the world, allowing scientists to learn a lot about the ocean. It could safely dive to 4000 feet, or 1200 meters, which isn’t nearly as deep as many modern submersibles, but which is still impressive.

This was long before remotely operated vehicles, so the submersible had to have a crew inside, both scientists and pilots. One of the pilots of Deepstar 4000 was a man named Joe Thompson. In 1966 Thompson maneuvered the craft to the ocean floor off the coast of California to deploy water sensors, in an area called the San Diego Trough. They touched down on the ocean floor and Thompson looked out of the tiny porthole, only to see something looking in at him.

Thompson reported seeing a fish with mottled gray-black skin and an eye the size of a dinner plate. He estimated it was 25 feet long, or over 7 ½ meters, which was longer than the Deepstar 4000 itself. Within seconds, the fish swam away into the darkness.

But that’s not the end of the story, because the water sensors the craft had already placed sensed the animal’s movement. There was definitely something really big near the craft. Even more interesting, an oceanographer had placed some underwater cameras in the area, and soon after Thompson’s sighting, the cameras took pictures of a huge gray fish.

While Thompson was positive the fish had scales, which he described as being as big around as coffee cups, the photo shows a more shark-like skin criss-crossed with scars. The oceanographer consulted with an ichthyologist, who identified the fish as a Pacific sleeper shark. We’ve talked about other sleeper sharks in episode 74. We don’t know a lot about these sharks, but they are gray, live in deep water, and can grow over 23 feet long, or 7 meters.

But Thompson was never satisfied with the identification of his mystery fish as a big Pacific sleeper shark. He was adamant that his fish had scales, a much larger eye than sharks have, and a tail that was more reminiscent of a coelacanth’s lobed tail than a shark’s tail.

One suggestion is that Thompson saw a new species of slickhead fish. Slickheads are deep-sea fish that can grow quite large, but we don’t know much about them since they live in such deep waters. The largest known species grows at least 8 feet long, or 2.5 meters, and possibly much longer. That’s the yokozuna slickhead, which was only discovered in 2021 by a scientific team studying cusk eels off the coast of Japan.

Most slickheads are small and eat plankton. This one was purplish in color, had lots of small sharp teeth, and was a strong, fast swimmer. When it was examined later, its stomach contents consisted of other fish, so it’s definitely a predator. Its eyes are also proportionately larger than a shark’s eyes. The slickhead gets its name because it doesn’t have scales on its head, but it does have scales on the rest of its body.

The yokozuna slickhead was discovered in a bay that’s well-known to both scientists and fishers, so the team didn’t believe at first that they could possibly have found a new species of fish there, especially one that was so big. But it definitely turned out to be new to science. More individuals have since been spotted, but they live very deep in the ocean, which explains why no one had seen one before. Interestingly, when the scientists first pulled the slickhead out of the water, they thought it looked a little like a coelacanth.

This episode was going to end there, but Richard from NC sent me another article about a whale mystery I’ve been talking about for years! It’s the so-called biotwang that we covered way back in episode 27.

In 2016 and early 2017, NOAA, the U.S. Coast Guard, and Oregon State University dropped a titanium-encased ceramic hydrophone into Challenger Deep. To their surprise, it was noisy as heck down there in the deepest water on earth. The hydrophone picked up the sounds of earthquakes, a typhoon passing over, ships, and whalesong—including the call of a whale researchers couldn’t identify. This is what it sounds like:

[biotwang whale call]

Well, as of September 2024, we now know what animal produces the biotwang call. It’s a whale, and one already known to science, although we don’t know much about it. It’s Bryde’s whale, a baleen whale that can grow up to 55 feet long, or almost 17 meters. The calls have all been associated with groups of Bryde’s whales, or a mother with a calf, so the scientists think the whales might use the unusual call to communicate location with its podmates. Bryde’s whales make lots of other sounds, and the scientists also think they might be responsible for some other mystery whale calls.

If you remember episode 193, about William Beebe’s mystery fish, he reported spotting a massive dark fish from his bathysphere a few decades before the Deepstar 4000 was built. He didn’t see it well enough to identify it and never saw it again. It just goes to show that there are definitely mystery animals just waiting to be discovered, whether it’s in the deep sea or perched in a treetop.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 397: Some Colorful Fishies

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Thanks to Cosmo, William, and Silas for their fishy suggestions this week!

You have until Sept. 13, 2024 to back the enamel pin Kickstarter!

Further reading:

The Handfish Conservation Project

Researchers Look in Tank and See Promising Cluster of Near-Extinct Babies

The unique visual systems of deep sea fish

A red handfish:

Another red handfish. This one is named Hector:

The black dragon fish:

The white-edged freshwater whipray [photo by Doni Susanto]:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week we return to the vertebrate world, specifically some strange and colorful fishies. Thanks to William, Cosmo, and Silas for their suggestions!

We’ll start with Silas’s suggestion, the red handfish. We talked about it before back in episode 189, but it’s definitely time to revisit it. When we last discussed it, scientists estimated there were fewer than 100 red handfish left in the wild, meaning it was in imminent danger of extinction. Let’s find out how it’s doing now, four years later.

The handfish gets its name because its pectoral fins look like big flat hands. It spends most of its time on the sea floor, and it uses its hands to walk instead of swimming. It can swim, although it’s not a very strong swimmer, and anyway if you had great big hands you might choose to walk on them too. It doesn’t have a swim bladder, which helps most fish stay buoyant.

All species of handfish are small, only growing to about 6 inches long at most, or 15 cm. This is surprising considering the handfish is closely related to anglerfish, and some anglerfish can grow over 3 feet long, or about a meter.

As for the red handfish specifically, it generally only grows about 4 inches long at most, or 10 cm, and it once lived in shallow water around much of Australia. These days, it’s only found on two reefs southeast of Tasmania. Some populations are bright red while some are pink with red spots. It has a wide downturned mouth that makes it look like a grumpy red toad with big hands.

So how is the red handfish doing? Four years ago it was almost extinct in wild, with fewer than 100 individuals alive. These days the Handfish Conservation Project estimates that the wild population is probably about the same, although because the red handfish is so small and hides so well among sea grass, algae, and rocks that make up its home, it’s hard to get a good count of how many are really alive. It’s also under even more pressure than before as an overpopulation of urchins is overgrazing the plants where it lives, which may sound familiar to you if you listened to episode 395 a few weeks ago. But there is one fantastic change that gives conservationists hope that the red handfish won’t go extinct after all.

The red handfish is so endangered, and its remaining habitat is so small, that a few years ago scientists decided they needed to start a captive breeding program. But even though the fish did just fine in captivity, they didn’t breed at first. Then, in November 2023, one of the fish laid 21 eggs and all 21 hatched safely. Hopefully it won’t be long until the babies are old enough to release into the wild.

The red handfish is one of very few fish that hatch into tiny baby fish instead of into a larval form. Newly hatched babies are only about 5 mm long. Most fish colonize new habitats after they float around aimlessly as larvae, until they grow enough to metamorphose into adults. Since the red handfish doesn’t have this larval stage, and babies just walk around on the sea floor finding tiny worms and other food, it’s hard for the fish to expand its range. Hopefully, as the captive breeding program continues and more young fish are released into the wild, scientists can start releasing red handfish into areas where they used to live.

Next, William asked about the dragon fish. We’ve talked about a few dragonfish before, in episodes 193 and 231, but there are lots of species in many genera in the family Stomiidae. Many have barbels with photophores at the end that lure prey, and most have long needle-like teeth and jaws that can open incredibly wide. They also have stretchy stomachs so they can hold whatever they manage to catch. As you may have guessed from these traits, the dragon fish lives in the deep sea where there’s little or no light from the surface.

You may wonder why deep-sea fish even have eyes if there’s no light. Fish that live in cave systems eventually evolve to be eyeless, since they don’t need their eyes to see and growing eyes is just a waste of their energy. It’s because even though there’s no sunlight in the deep sea, there is light from lots of different organisms. Many, many deep-sea animals produce bioluminescent light to attract mates or trick smaller animals into coming closer.

Any sunlight that does find its way to the depths of the ocean is blue, because blue has the shortest wavelength and can travel farther. Red wavelengths are longest so that red is the first color lost when you start descending into the water. One article that I’ve linked to in the show notes mentions that if a diver gets a cut, the blood looks brown or even black if the water is deep enough. That’s creepy.

As a result, deep-sea fish are most sensitive to the color blue. Most of them can’t perceive red at all because there just isn’t any red in their environment. And that’s where the dragon fish comes in, because some species of dragon fish can not only see red, they produce red light that illuminates everything around them. A fish or other animal swimming along has no idea that it’s lit up like it’s under a red spotlight because it can’t even see that color.

At least one species, the black dragon fish, perceives red light very differently from the way other animals do. As far as we know it’s unique among all animals. Its eyes contain a photosensitizer derived from chlorophyll, which allows it to see shorter lightwaves. Chlorophyll is found in plants and some bacteria, and it’s actually a specialized pigment that absorbs energy from light. It’s the reason why plants are green. But the black dragonfish uses the chlorophyll it digests to perceive red light.

But remember how dragon fish have giant sharp fangs and will eat pretty much anything they can swallow? Where does the black dragon fish get the chlorophyll it needs? There aren’t any plants in the deep sea anyway.

The answer seems to be that the black dragon fish eats a whole lot of copepods, tiny crustaceans that live throughout the world. The particular species of copepods that the black dragon fish prefers contain a type of chlorophyll.

Finally, Cosmo wanted to learn about the freshwater stingray. We talked about it in episode 296, but mostly we concentrated on the South American fish in that episode. There are freshwater stingrays that live in other parts of the world, such as Asia. This includes the white-edge freshwater whipray, which is extremely rare and only found in four rivers in Southeast Asia.

The white-edge freshwater whipray grows up to two feet across, or 60 cm, with a thin tail about two and a half times longer than the body itself so that technically it can grow around 6 and a half feet long, or 2 meters. Most of that length is tail, though. It’s mostly brown so it can hide in the sandy mud at the bottom of the river, with black dermal denticles down the middle of its back. The tail is mostly white, though, and has two long stinging spines that can be over 3 inches long, or 8 cm.

While the white-edged whipray lives in rivers, it can also tolerate brackish water where the ocean and the river waters mix. It eats small animals it finds on the bottom of the river, including crustaceans and mollusks. It’s endangered due to habitat loss, overfishing, and pollution.

The white-edged whipray is so rare these days that it’s unlikely that anyone would accidentally step on one in the water. But if they did, the ray would whip its long tail up and jab the spines into the person’s leg or foot. The spines can do a lot of damage on their own, but the venom they inject makes the wound incredibly painful and can even potentially kill the person.

If you plan to do some wading in a South Asian river anytime soon, make sure to shuffle your feet as you walk to scare away any potential whiprays before you step right on it.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

 

Episode 316: The Blobfish and a Round Bunny

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This week we learn more about the blobfish thanks to Matilde’s suggestion, and we’ll also learn about a primitive rabbit.

Further reading:

In Defense of the Blobfish: Why the ‘World’s Ugliest Animal’ Isn’t as Ugly as You Think It Is

A rare rabbit plays an important ecological role by spreading seeds

The Amami Rabbit: A Living Fossil in the Wilds of Amami Ōshima [amazing photos in this article!]

The blobfish as we usually see it:

The blobfish as it looks when it’s in its deep-sea home:

The Amami rabbit is so so so round:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week we’re going to learn a little more about the blobfish, which is Matilde’s suggestion, and we’ll also talk about an unusual primitive rabbit that’s still alive today.

We talked about the blobfish briefly in episode 231. The blobfish lives on the sea floor in deep water near Australia and New Zealand. It grows about a foot long at most, or 30 cm, and has weak muscles and a weak skeleton, but it doesn’t need to be any stronger since the intense pressure of the water presses in around the fish all the time. Its gelatinous flesh is slightly less dense than the water around it, which means it can float just above the sea floor without much effort, just drifting along, giving its tail and broad fins a little flap every so often. It eats whatever detritus floats down from far above, although it also really likes to eat small crustaceans that live on the sea floor.

But wait, you may be thinking, I’ve seen pictures of the blobfish and it looks like a pinkish blob with a cartoony frown and a droopy nose. Is that blobfish a different one from the one I just described?

No! The trouble is that the blobfish lives in really deep water, up to 4,000 feet below the surface, or 1200 meters. That means that there’s up to 4,000 feet of water above the fish, and if you’ve ever had to carry a bucket of water more than a few steps, you’ll know that water is really heavy. So the blobfish has 4,000 feet of water pressing on it from all directions. This is naturally called water pressure, and at the depths where the blobfish lives, it’s 120 times higher than water pressure in, for instance, your bathtub.

At that water pressure, you could not survive for even one second. You would be instantly crushed into a messy blob if you were suddenly transported into water that deep, because your body is adapted to live on the earth’s surface. But the opposite is true for the blobfish. If it was suddenly transported to the earth’s surface, or at least the water’s surface, without all that comfortable pressure keeping its body in place like a really big exoskeleton you can swim through, the blobfish would expand. And that’s exactly what happens when a fishing net catches a blobfish and pulls it to the surface. It just goes BLOB all over the place.

The blobfish was voted the world’s ugliest animal in 2013, which doesn’t seem fair since no one looks good when they’ve exploded into a blob.

When the blobfish is alive in its deep-sea home, it’s silvery or grayish with little spikes all over its body. It’s a member of the family Psychrolutidae, sometimes called toadfish, and it has little black eyes near the top of its head sort of like a toad. Its head is large and wide, while its body tapers to a thin little flat tail.

We know almost nothing so far about the blobfish, but we do know a bit about some of its close relatives like the blob sculpin. The blob sculpin lives in the North Pacific Ocean in even deeper water than the blobfish, up to 9200 feet deep, or 2800 meters. That’s about a mile and three-quarters deep, or almost 3 kilometers. Deep-sea animals are mostly solitary, but the blob sculpin gathers in large numbers to spawn. The females choose a nesting area and they all lay their eggs in the same place. Then the males release sperm into the water that fertilizes the eggs. Some nesting areas have been found to contain well over 100,000 eggs! Not only that, but the females guard the nesting area, and as they hover over their eggs, their slow-moving fins help keep the eggs clean of sand and sediment, which allows the eggs to absorb more oxygen. It’s the first documented case of a deep-sea fish taking care of its eggs.

Deep-sea animals often live for a long time, and it’s estimated that the blobfish might live to be as much as 130 years old.

That’s about all we know about the blobfish right now, so let’s finish with some information about a different cute round animal, although not a blobby one. It’s the Amami rabbit that only lives on two tiny islands off the southern coast of Japan.

The Amami rabbit used to live throughout Asia but as modern species of rabbit evolved, it eventually died out on the mainland. Now it only survives on these two small islands, and although it’s now a protected species, it’s still endangered. It’s especially vulnerable to habitat loss and introduced predators like dogs and cats. There are probably only about 5,000 individuals alive today, most of them on Amami Island with only a few hundred on Tokuno Island.

The Amami rabbit differs from other rabbits in a number of ways. Its eyes are smaller, its ears are smaller, and it’s shaped differently from other rabbits, with a chonky body and short legs. It also lives in forested areas instead of open grasslands. It’s nocturnal, with thick dark brown fur and long claws that it uses to dig burrows and climb steep hillsides.

A female Amami rabbit only has babies once a year, called kits or kittens, and usually only one or two kits are born at a time. In autumn the mother rabbit digs a special burrow that may be several feet deep, or up to a meter, somewhere away from her regular burrow. She brings leaves in to line the nesting chamber, where she gives birth to her kits. But she doesn’t stay with her babies all the time. In fact, she leaves them and only comes back to feed them about once a day or every other day. To keep them safe while she’s gone, she closes the entrance to the burrow so snakes and other predators can’t get in. When she returns, she digs the entrance open and spends a few minutes feeding her kits. Then she leaves again and closes the entrance behind her.

When the babies are a little over a month old, they start digging their way out of the nest on their own to explore. At that point the mother leads them to her home burrow where they stay for a few more months before they leave to find their own territories.

The Amami rabbit eats plants, especially grass and ferns, but it also eats acorns and fruit. A study published in January 2023 reported that the rabbit eats the fruit of a parasitic flowering plant called Balanophora, including swallowing the seeds whole. The seeds travel through the rabbit’s digestive system unharmed and the rabbit poops them out later, which allows them to sprout in an area far from the parent plant. Since Balanophora doesn’t produce chlorophyll and instead needs a host plant that can provide it with nutrients, having a rabbit help spread its seeds is important. This discovery was a surprise to the scientists studying the rabbit, because modern species of rabbit don’t usually eat seeds.

Who knows how many more surprises the Amami rabbit and the blobfish might hold? Hopefully scientists will continue to learn more about them so they can be better protected.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 314: Animals Discovered in 2022

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Let’s learn about some of the animals discovered in 2022! There are lots, so let’s go!

Further Reading:

In Japanese waters, a newly described anemone lives on the back of a hermit crab

Rare ‘fossil’ clam discovered alive

Marine Biologists Discover New Giant Isopod

Mysterious ‘blue goo’ at the bottom of the sea stumps scientists

New Species of Mossy Frog Discovered in Vietnam

A Wildlife YouTuber Discovered This New Species of Tarantula in Thailand

Meet Nepenthes pudica, Carnivorous Plant that Produces Underground Traps

Scientists discover shark graveyard at the bottom of the ocean

Further Watching:

JoCho Sippawat’s YouTube channel

A newly discovered sea anemone (photo by Akihiro Yoshikawa):

A mysterious blue blob seen by a deep-sea rover:

A newly discovered frog:

A newly discovered tarantula (photo by JoCho Sippawat):

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

It’s the 2022 discoveries episode, where we learn about some of the animals discovered in 2022! Most of the time these animals were actually discovered by scientists before 2022, but the description was published in that year so that’s when we first learned about them. And, of course, a lot of these animals were already known to the local people but had never been studied by scientists before. There are lots of animals in the world but not that many scientists.

The great thing is, so many animals get discovered in any given year that I have to pick and choose the ones I think listeners will find most interesting, which in a stunning coincidence turns out to be the ones that I personally find most interesting. Funny how that works out.

We’ll start in the ocean, which is full of weird animals that no human has ever seen before. It’s about a hermit crab who carries a friend around. The hermit crab was already known to science, but until a team of scientists observed it in its natural habitat, the deep sea off the Pacific coast of Japan, no one realized it had an anemone friend.

The sea anemone is related to jellyfish and is a common animal throughout the world’s oceans. Some species float around, some anchor themselves to a hard surface. Many species have developed a symbiotic relationship with other animals, such as the clownfish, which is sometimes called the anemonefish because it relies on the anemone to survive. Anemones sting the way jellyfish do, but it doesn’t sting the clownfish. Researchers aren’t sure why not, but it may have something to do with the clownfish’s mucus coating. Specifically, the mucus may have a particular taste that the anemone recognizes as belonging to a friend. If the anemone does accidentally sting the clownfish, it’s still okay because the fish is generally immune to the anemone’s toxins.

The clownfish lives among the anemone’s tentacles, which protects it from predators, and in return its movements bring more oxygen to the anemone by circulating water through its tentacles, its droppings provide minerals to the anemone, and because the clownfish is small and brightly colored, it might even attract predators that the anemone can catch and eat.

Anemones also develop mutualistic relationships with other organisms, including a single-celled algae that lives in its body and photosynthesizes light into energy. The algae has a safe place to live while the anemone receives some of the energy from the algae’s photosynthesis. But some species of anemone have a relationship with crabs, including this newly discovered anemone.

The anemone anchors itself to the shell that the hermit crab lives in. The crab gains protection from predators, who would have to go through the stinging tentacles and the shell to get to the crab, while the anemone gets carried to new places where it can find more food. It also gathers up pieces of food that the crab scatters while eating, because crabs are messy eaters.

The problem is that hermit crabs have to move into bigger shells as they grow. Anemones can move, but incredibly slowly. Like, snails look like racecar drivers compared to anemones. The anemone moves so slowly that the human eye can’t detect the movement.

What the team of scientists witnessed was a hermit crab spending several days carefully pushing and pinching the anemone to make it move onto its new shell. If it wasn’t important, the crab wouldn’t bother. The sea anemone hasn’t yet been officially described since it’s still being studied, but it appears to be closely related to four other species of anemone that also attach themselves to the shells of other hermit crab species.

In other marine invertebrate news, a researcher named Jeff Goddard was turning rocks over at low tide at Naples Point, California a few years ago. He was looking for sea slugs, but he noticed some tiny clams. They were only about 10 mm long, but they extended a white-striped foot longer than their shells. Goddard had never seen anything quite like these clams even though he was familiar with the beach and everything that lived there, so he took pictures and sent them to a clam expert. The expert hadn’t seen these clams before either and came to look for the clams in person. But they couldn’t find the clams again. It took ten trips to the beach and an entire year before they found another of the clams.

They thought the clam might be a new species, but part of describing a new species is examining the literature to make sure the organism wasn’t already described a long time ago. Eventually the clam research team did find a paper with illustrations of a clam that matched, published in 1937, but that paper was about a fossilized clam.

They examined the 1937 fossil shell and compared it to their modern clam shell. It was a match! But why hadn’t someone else noticed these clams before? Even Goddard hadn’t seen them, and he’s a researcher that spends a lot of time along the coast looking specifically for things like little rare clams. Goddard thinks the clam has only recently started extending its range northward, especially during some marine heatwaves in 2014 through 2016. He suspects the clam’s typical range is farther south in Baja California, so hopefully a future expedition to that part of the Pacific can find lots more of the clams and we can learn more about it.

We talked about deep-sea isopods just a few weeks ago, in episode 311. They’re crustaceans related to crabs and lobsters, but also related to roly-polies that live on land. The deep-sea species often show deep-sea gigantism and are referred to as giant isopods, and that’s what this newly discovered species is. It was first found in 2017 in the Gulf of Mexico and is more slender than other giant isopods. The largest individual measured so far is just over 10 inches long, or 26 cm, which is almost exactly half the length of the longest giant isopod ever measured. It’s still pretty big, especially if you compare it to its roly-poly cousins, also called pillbugs, sow bugs, or woodlice, who typically grow around 15 mm at most.

Before we get out of the water, let’s talk about one more marine animal. This one’s a mystery that I covered in the October 2022 Patreon episode. It was suggested by my brother Richard, so thank you again, Richard!

On August 30, 2022, a research team was off the coast of Puerto Rico, collecting data about the sea floor. Since the Caribbean is an area of the ocean with high biodiversity but also high rates of fishing and trawling, the more we can learn about the animals and plants that live on the sea floor, the more we can do to help protect them.

When a remotely operated vehicle dives, it sends video to a team of scientists who can watch in real time and control where the rover goes. On this particular day, the rover descended to a little over 1,300 feet deep, or around 407 meters, when the sea floor came in view. Since this area is the site of an underwater ridge, the sea floor varies by a lot, and the rover swam along filming things and taking samples of the water, sometimes as deep as about 2,000 feet, or 611 meters.

The rover saw lots of interesting animals, including fish and corals of various types, even a fossilized coral reef. Then it filmed something the scientists had never seen before. It was a little blue blob sitting on the sea floor.

The blue blob wasn’t moving and wasn’t very big. It was shaped roughly like a ball but with little points or pimples all over it and a wider base like a skirt where it met the ground, and it was definitely pale blue in color.

Then the rover saw more of the little blue blobs, quite a few of them in various places. The scientists think it may be a species of soft coral or a type of sponge, possibly even a tunicate, which is also called a sea squirt. All these animals are invertebrates that don’t move, which matches what little we know about the blue blob.

The rover wasn’t able to take a sample from one of the blue blobs, so for now we don’t have anything to study except the video. But we know where the little blue blobs are, so researchers hope to visit them again soon and learn more about them.

It wouldn’t be a newly discovered species list without at least one new frog. Quite a few frogs were discovered in 2022, including a tree frog from Vietnam called Khoi’s mossy frog. It lives in higher elevations and is pretty big for a tree frog, with a big female growing over 2 inches long, or almost 6 cm, from snout to vent. Males are smaller. It’s mostly brown and green with little points and bumps all over that help it blend into the moss-covered branches where it lives. That’s just about all we know about it so far.

Our next discovery is an invertebrate, a spider that lives in bamboo. Specifically it lives in a particular species of Asian bamboo in Thailand, and when I say it lives in the bamboo, I mean it really does live inside the bamboo stalks. Also, when I say it’s a spider, specifically it’s a small tarantula.

It was first discovered by a YouTuber named JoCho Sippawat, who travels around his home in Thailand and films the animals he sees. I watched a couple of his videos and they’re really well done and fun, and he’s adorable even when he’s eating gross things he finds, so I recommend his videos even if you don’t speak the language he speaks. I’m not sure if it’s Mandarin or another language, and I’m not sure if I’m pronouncing his name right either, so apologies to everyone from Thailand for my ignorance.

Anyway, Sippawat found a tarantula where no tarantula should be, inside a bamboo stalk, and sent pictures to an arachnologist. That led to a team of scientists coming to look for more of the spiders, and to their excitement, they found them and determined right away that they’re new to science. It was pretty easy to determine in this case because even though there are more than 1,000 species of tarantula in many parts of the world, none of them live in bamboo stalks. The new spider was placed in a genus all to itself since it’s so different from all other known tarantulas.

It’s mostly black and dark brown with narrow white stripes on its legs, and its body is only about an inch and a half long, or 3 1/2 cm. It can’t make holes into the bamboo plants itself, so it has to find a hole made by another animal or a natural crack in the bamboo. It lines its bamboo stalk with silk to make a little home, and while there’s a lot we don’t know yet about how it lives, it probably comes out of its home to hunt insects and other small animals since tarantulas don’t build webs.

Finally, let’s wrap around to the sea anemone again, at least sort of. If you remember episode 129, we talked about the Venus flytrap sea anemone, which is an animal that looks kind of like a carnivorous plant called the Venus flytrap. We then also talked about a lot of other carnivorous plants, including the pitcher plant. Well, in 2022 a new species of pitcher plant was discovered that has underground traps.

The pitcher plant has a type of modified leaf that forms a slippery-sided pitcher filled with a nectar-like liquid. When an insect crawls down to drink the liquid, it falls in and can’t get out. It drowns and is dissolved and digested by the plant. Almost all known carnivorous plants are pretty small, but the largest are pitcher plants. The biggest pitcher plant known is from a couple of mountains in Malaysian Borneo, and its pitchers can hold over 2 ½ liters of digestive fluid. The plant itself is a messy sort of vine that can grow nearly 20 feet long, or 6 meters. Mostly pitcher plants just attract insects, especially ants, but these giant ones can also trap frogs, lizards, rats and other small mammals, and even birds.

The newly discovered pitcher plant grows in the mountainous rainforests of Indonesian Borneo and is relatively small. Unlike every other pitcher plant known, its pitchers develop underground and can grow a little over 4 inches long, or 11 cm. Sometimes they grow just under the surface, with leaf litter or moss as their only covering, but sometimes they grow deeper underground. Either way, they’re very different from other pitcher plants in other ways too. For one thing, scientists found a lot of organisms actually living in the pitchers and not getting eaten by the plant, including a new species of worm. Scientists aren’t sure why some animals are safe in the plant but some animals get eaten.

The new pitcher plant is found in parts of Indonesian Borneo that’s being turned into palm oil plantations at a devastating rate, leading to the extinction or threatened extinction of thousands of animal and plant species. The local people are also treated very badly. Every new discovery brings more attention to the plight of the area and makes it even more urgent that its ecosystems are protected from further development. The fastest way to do this would be for companies to stop using so much palm oil. Seriously, it’s in everything, just look at the ingredients list for just about anything. I try to avoid it when I’m grocery shopping but it’s just about impossible. I didn’t mean to rant, but the whole palm oil thing really infuriates me.

You know what? Let’s have one more discovery so we don’t end on a sour note.

A biodiversity survey of two of Australia’s marine parks made some really interesting discoveries in 2022. This included a new species of hornshark that hasn’t even been described yet. It’s probably related to the Port Jackson shark, which grows to around five and a half feet long, or 1.65 meters, and is a slow-moving shark that lives in shallow water off the coast of most of Australia. Instead of a big scary mouth full of sharp teeth, the Port Jackson shark has a small mouth and flattened teeth that allow it to crush mollusks and crabs. The newly discovered shark lives in much deeper water than other hornsharks, though, around 500 feet deep, or 150 meters.

Another thing they found during the survey wasn’t a new species of anything, but it’s really cool so I’ll share it anyway. It was a so-called shark graveyard over three miles below the ocean’s surface, or 5400 meters. The scientists were trawling the bottom and when they brought the net up to see what they’d found, it was full of shark teeth–over 750 shark teeth! They were fossilized but some were from modern species while some were from various extinct species of shark, including a close relative of Megalodon that grew around 39 feet long, or 12 meters. No one has any idea why so many shark teeth are gathered in that particular area of the sea floor.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 311: The Mystery Deep-Sea Spider

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Thanks to Llewelly for this suggestion, and thanks to Dr. Thomas A. Hegna for providing me with the two papers I reference in this episode!

Images are taken from the papers.

The mystery “spider”:

Long-legged isopods:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

My carefully planned out episode schedule has already gotten messed up, but I got excited about this topic and couldn’t wait to share it! It’s a mystery invertebrate from the deep sea that has been solved! Thanks to Llewelly for bringing this to my attention, and thanks to arthropod paleontologist Dr. Thomas A. Hegna for posting this information on Mastodon in the first place, and for providing the relevant papers to me. People are pretty great.

I knew about this topic from the book The Search for the Last Undiscovered Animals by Karl Shuker, but I hadn’t been able to find out more. Until now.

In the late 1980s, a program called DISCOL 1 was launched to study disturbances on the sea floor due to underwater mining. It focused on the deep sea in the South Pacific. One of the things the expedition did was drop underwater cameras with bait tied to them. When an animal came to investigate the bait, the camera took pictures. I have a birdfeeder like this now although I don’t have to drop it anywhere.

In February 1989, the camera descended to about 13,600 feet, or 4,150 meters, in the Peru basin. When it was hauled up a few days later and the pictures retrieved, the scientists saw something they didn’t recognize on 20 of the photos. It looked like a spider.

The scientists were able to get a good idea of the animal’s size because they knew how big the bait was and how big the metal rod was that the bait was tied to. The animal’s body was about 2 and a half inches long, or 6 cm, and about half that width, not counting its long, jointed legs. It had five pairs of appendages, including three pairs of walking legs. The other two pairs of appendages were longer and might be feelers of some kind, with the front pair possibly used to manipulate food. The estimated legspan was almost 8 inches across, or more than 20 cm.

The scientists published a short article about the finding later in 1989 and proposed that the animal be tentatively placed in the phylum Arachnida with spiders and their relations. But this placement is a big deal, because there are no known spider relations that live in deep water. Some spiders have evolved to live in water at least part of the time, but they always have to have access to the air.

For a long time that’s all anyone knew. Most scientists thought the animal was probably a pycnogonid [pik-NA-gunid], an arthropod commonly called a sea spider although it’s not actually an arachnid. We talked about sea spiders in episode 105, so I’ll revisit some of the information from that episode.

Sea spiders live throughout the world’s oceans and there are well over a thousand known species. Most are small and live in shallow water, but a few live in water up to 23,000 feet deep, or 7,000 meters. The biggest species live in the cold waters around Antarctica, with the very largest individual ever found having a legspan of about 27 inches across, or 70 cm.

The sea spider has four pairs of legs, although a few species have five or six pairs of legs instead. Some species have one or two pairs of simple eyes, but other species have no eyes at all. The body is quite small in relation to the legs, which are extremely long, which means the digestive tract is actually partly in the legs, because the body is too small for it. It walks along the bottom of the ocean or may swim by pulsing its long legs like a jellyfish with legs instead of a bell. In species that swim, the legs may be lined with long bristles.

Some species have mouthparts, but most eat using a proboscis that it uses to suck fluids out of its prey. Some species have spines at the tip of the proboscis. It sticks its proboscis into a sponge, worm, jelly, sea anemone, or other invertebrate, injects digestive fluids that liquefy the surrounding tissues, and slurps the fluids up. Sometimes this kills the prey animal, sometimes it doesn’t.

All this does sound a lot like the spider-like animal photographed in 1989. But in 2004 a new paper was published about the animal, where the original scientists teamed with some other experts to re-examine the photographs. Their conclusion is that the mystery animal wasn’t a spider or a sea spider but something else: a munnopsidid isopod.

Isopods are crustaceans that have been around for at least 300 million years. They live all over the world, on land and in both fresh water and in the ocean. The animal sometimes called the woodlouse or pill bug or roly-poly or sow bug are actually isopods. All isopods have segmented exoskeletons, as you may have seen in roly-polies or whatever you call those little guys, and all have two pairs of antennae and seven pairs of jointed legs.

Isopods are very common animals in the ocean and the most common isopods are members of the family Munnopsidae. Most have short legs but some have long legs, including some species in the subfamily Bathyopsurinae.

While Munnopsids are common, there are only four species in two genera in Bathyopsurinae. The biggest isopods live in the deep sea and while these four species are pretty big, up to 2 and a half inches long, or 6 cm, they’re nowhere near the size of the largest isopods known. That would be the giant isopod that can grow up to 20 inches long, or 50 cm, but it’s not closely related to these four species.

As to which species the mystery isopod belongs to, the photographs aren’t close enough or clear enough for a definite identification. It’s possible the mystery isopod belongs to a species unknown to science.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 290: Lobsters!

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Thanks to Pranav for this week’s suggestion, lobsters!

Happy birthday to Jake!!

Visit Dr. Oné R. Pagán’s site for links to his podcast and his free book Arrow: The Lucky Planarian! You can also order his other books from your favorite book store. Here’s the direct link to his interview with me!

Further reading:

Don’t Listen to the Buzz: Lobsters Aren’t Actually Immortal

An ordinary lobster:

A blue lobster!

The scampi looks more like a prawn/shrimp than a lobster, but it’s a lobster:

 

The rosy lobsterette is naturally red because it lives in the deep sea:

The deep-sea lobster Dinochelus ausubeli was only discovered in 2007 and described in 2010:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

As invertebrate August continues, this week we’re going to talk about lobsters. Thanks to Pranav for the suggestion!

But first, we have a birthday shout-out! A great big happy birthday this week to Jake! I hope your birthday is epic fun!

I’d also like to let you know that Dr. Oné R Pagán interviewed me recently about my book, Beyond Bigfoot & Nessie: Lesser-Known Mystery Animals from Around the World, and you can hear that interview on his podcast, the Baldscientist Podcast. Baldscientist is all one word. I’ll put a link in the show notes. While you’re at it, you should definitely buy his books, including his latest one, Drunk Flies and Stoned Dolphins: A Trip Through the World of Animal Intoxication, which just came out this year and is a lot of fun, as well as being full of interesting science! He also has a free children’s story called Arrow, the Lucky Planarian that you can download and read. It’s completely charming and you’ll learn a lot about planarians, which are also called flatworms, which are invertebrates, so this is all coming together!

This week’s episode isn’t about planarians, though, but about lobsters. I don’t think we’ve ever discussed lobsters on the podcast before, oddly enough, but it’s been on my ideas list for a long time. When Pranav emailed me recently to suggest we do a lobster episode, I realized it was time! Time for lobsters!

The lobster is a crustacean, and while there are plenty of different lobsters in the world, we’re going to focus on the clawed lobsters this time. There are lots of them, all grouped in the family Nephropidae.

The lobster has eight legs that it walks on, and two more legs with pincers. That’s why it’s in the order Decapoda. Deca means ten and poda means feet. Ten feet. Some of which can pinch you if you’re not careful.

The lobster uses its claws to defend itself from potential predators, and uses them to grab and kill small animals. It eats pretty much anything it can find, from fish and squid to sea stars and mollusks, to dead animals and some plant material. But its claws are too big and clumsy to use to eat with, which is why it has much smaller pincers on its next pairs of legs. These pincers are equipped with chemoreceptors that allow the lobster to taste its food before it actually eats it, which is a neat trick.

The lobster uses these small claws to pull its food into smaller pieces and convey it to the mouthparts, which are under its head. Some mouthparts have sensory hairs that can taste food, some have sharp spines that act as teeth to tear food into smaller pieces, and others are small and just flutter to help keep pieces of food from floating away. The stomach is only about an inch away from the mouth, or about 2.5 cm, no matter the size of the lobster. The stomach itself, and the short esophagus leading to the stomach, are lined with chitin spines that act like teeth to grind food up while enzymes break it down to fully digest it. This seems like a really complicated way to eat, but it’s actually not all that different from the way we eat, it’s just that instead of mouthparts and stomach teeth, we do all our grinding up of food in the mouth with just one set of teeth.

The lobster’s body is protected by an exoskeleton made of chitin, but the trouble with exoskeletons is that they don’t grow. The lobster has to shed its exoskeleton every so often and grow a new one that fits better, and until the new exoskeleton has hardened, the lobster is vulnerable and will usually hide. This can take several weeks. When a lobster is young and growing rapidly, it may molt its exoskeleton every few months or even more often, while an adult lobster typically only molts once every year or two.

Molting takes energy, though, and the bigger a lobster is, the more energy it takes to molt. It’s not like taking off a shirt. The lobster has to wriggle carefully out of its exoskeleton through a split between its tail and abdomen, making sure not to hurt its soft body in the process, and it even molts its stomach teeth, more properly called a gastric mill.

It’s a long, difficult process, during which time the lobster is mostly helpless. Some studies indicate that something like 10% of all lobsters actually die during the molting process. A lobster usually eats its shed exoskeleton in order to extract calcium from it, which helps its new exoskeleton harden faster.

Unlike many animals, lobsters keep growing throughout their lives. Since they can live a long time, that means sometimes people catch really big lobsters. The biggest ever reliably measured was an American lobster caught in 1977 off the coast of Nova Scotia, Canada in North America. It weighed 44 lbs, 6 oz, or 20.14 kg and was 3.5 feet long, or 106 cm. A more ordinary weight of a good-sized lobster is about 2 lbs, or 910 grams.

The lobster can definitely live at least 50 years, and some researchers suggest it can live much longer than that. But it’s really hard to tell the age of a lobster. You can’t go by size since individual lobsters grow at different rates depending on how much food they can find and other factors. A study published in September 2021 reports that a DNA test of genetic modifications that lobsters and other animals accumulate during their lives can determine a lobster’s age with a good degree of accuracy. This is important since it will help conservationists learn more about lobster populations, many of which are under increasing pressure from commercial fishing.

There’s a lot of talk online about how the lobster is actually immortal, and that if nothing kills it, it will just live forever. This rumor got started when scientists reported that lobsters express an enzyme called telomerase that repairs damage to DNA sequences at the ends of chromosomes. Most adult animals lose the ability to express telomerase, but the lobster doesn’t.

But lobsters aren’t immortal. A really old lobster stops shedding its exoskeleton, which slowly becomes more and more battered. The exoskeleton is part of the lobster’s body and can contract bacterial infections when it’s injured. Sometimes the infections are bad enough that it fuses the exoskeleton to the body permanently, so if the lobster does eventually get to the point where it can molt, it gets stuck trying to and dies. Sometimes the exoskeleton just rots away, which leads to the lobster’s death.

Still, the telomerase probably helps the lobster live for such a long time. Now that scientists have a way to determine a lobster’s actual age without harming it, hopefully soon we’ll learn more about how old they really get. We might be surprised, who knows?

Most species of lobster are brown, black, or greenish, which helps them hide on the sea floor. When a lobster is cooked by boiling, chemicals in its exoskeleton react with the hot water and turn it bright red. But sometimes—like, once every 10 million lobsters—a live lobster is found that is red. Researchers aren’t sure what causes this coloration.

Sometimes lobsters can be blue too. It’s still rare but not as rare as red coloration, estimated at about one every two million lobsters. While some species of lobster are naturally dark blue or even dark purple, a blue lobster is a really pretty shade of bright blue. It’s caused by a genetic mutation that results in it producing more of a protein that reacts with the pigments in its body, turning it blue. Since blue lobsters are so striking and attractive, lobster fishers usually either throw blue lobsters back or donate them to local aquariums. People sometimes assume blue lobsters are poisonous even though they’re not, so mostly no one wants to eat them anyway.

Lobsters are closely related to crabs and shrimp, and some clawed lobsters look a lot like their close relatives. This includes the scampi, which is the pinkish and silvery-white coloration of a prawn or shrimp, and only grows about 10 inches long at most, or 25 cm. It lives in parts of the northeastern Atlantic and parts of the Mediterranean Sea, where it digs a burrow in the muddy sea floor and spends most of its time hiding. It eats worms, small fish, jellyfish, and anything else it can catch. There are other species of scampi that live in other parts of the world’s oceans too.

Another lobster that looks even more like a shrimp is the rosy lobsterette, which only grows about 5 inches long, or 13 cm, and which is naturally red. This isn’t a rare coloration but an adaptation to its habitat. Unlike most lobsters, which live in shallow coastal waters, the rosy lobsterette lives in much deeper water where there’s very little light. As we’ve talked about before, the wavelength of light that is red can’t penetrate very far into water, so a red animal in the deep sea is basically invisible. A lot of deep-sea animals can’t even perceive the color red. The rosy lobsterette lives in the Gulf of Mexico, around the Caribbean, and in the western Atlantic Ocean.

There are actually quite a few species of lobster that live in the deep sea, with more being discovered every so often. In 2010 a new species of deep-sea lobster was described, Dinochelus ausubeli, which lives near the Philippines in South Asia. It was discovered during the ten-year Census of Marine Life, which sponsored 540 expeditions by thousands of scientists all over the world. It only grows a few inches long, or about 5 cm, and is mostly transparent with some pinkish coloring. It has one really long, thin, spiny claw with a bulbous base, while the other claw is much smaller.

There are a whole lot of other clawed lobster species, some of them known from only a few specimens. The Cape lobster, for instance, lives off the coast of South Africa in rocky areas, and even though it’s been known to science since the late 18th century, we don’t know much about it. It’s small, only growing about 4 inches long, or 10 cm, and ranges in coloration from greenish to yellowish to brown, even sometimes red, and it looks like a miniature version of the European or American lobsters although it’s not very closely related. In 1992 someone found one, which was such a rare occurrence that it was reported in the news. It was only the 14th specimen ever found at the time, although the publicity it received got other people out looking for the little lobster and more have been found since.

In other words, there are undoubtedly lots more species of lobster than we know about, just waiting to be discovered.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 288: Mystery Invertebrates

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Thanks to Joel for suggesting this week’s topic!

Happy birthday to Fern this week!

Further reading:

Small, rare crayfish thought extinct is rediscovered in cave in Huntsville city limits

Hundreds of three-eyed ‘dinosaur shrimp’ emerge after Arizona monsoon

An invertebrate mystery track in South Africa

The case of the mysterious holes in the sea floor

Contemplating the Con Rit

The Shelton Cave crayfish, rediscovered:

The three-eyed “tadpole shrimp” or “dinosaur shrimp,” triops [photo from article linked above]:

A leech track in South Africa [photo from article linked above]:

A track, or at least a series of holes, discovered in the deep seafloor [photos from article linked above]:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

Thanks to Joel who suggested we do an episode about mystery invertebrates! It took me a while, but I think you’re really going to like this episode. Some of the mysteries are solved and some are not, but they’re all fun.

Before we get to the mystery animals, though, we have a birthday shout-out! A great big happy birthday to Fern! I hope you have your favorite type of birthday cake or other treat and get to enjoy it with your loved ones.

Our first mystery starts in a cave near Huntsville, Alabama in the southern United States, which is in North America. Shelta Cave is a relatively small cave system, only about 2,500 feet long, or 760 meters. That’s about half a mile. It’s a nature preserve now but in the early 1900s it was used as an underground dance hall with a bar and everything.

Biologist John Cooper studied the cave’s aquatic ecosystem in the 1960s when he was doing his dissertation work. His wife Martha helped him since they were both active cavers. At the time, the cave ecosystem was incredibly diverse, including three species of crayfish. One was called the Shelta Cave crayfish, which was only a few inches long, or about 5 cm, mostly translucent or white since it didn’t have any pigment in its body, and with long, thin pincers.

It was rarer than the cave’s other two crayfish species, and unlike them it had only ever been found in Shelta Cave. From 1963 to 1975, only 115 individuals had been confirmed in repeated studies of the cave’s ecosystem.

Then, in the 1970s, several things happened that caused a serious decline in the diversity of life in the cave.

The first was development of the land around the cave into subdivisions, which meant that more pesticides were used on lawns and flower beds, which made its way into the groundwater that entered the cave. It also meant more people discovering the cave and going in to explore, which was disturbing a population of gray bats who also lived in the cave. To help the bats and keep people out, the park service put a gate over the entrance, but the initial gate’s design wasn’t a very good one. It kept people out but it also made it harder for the bats to go in and out, and eventually the bats gave up and moved out of the cave completely. This really impacted the cave’s ecosystem, since bats bring a lot of nutrients into a cave with their droppings and the occasional bat who dies and falls to the cave floor.

The gate has since been replaced with a much more bat-friendly one, but studies afterwards showed that a lot of the animals found in the cave had become rare. The Shelta Cave crayfish had disappeared completely. One was spotted in 1988 but after that, nothing, and the biologists studying the cave worried that it had gone extinct.

Then, in 2019, a team of scientists and students surveying life in the cave spotted a little white crayfish with long, thin pincers in the water. The team leader dived down and scooped it up with his net to examine more closely. The crayfish turned out to be a female Shelta Cave crayfish with eggs, which made everyone excited, and after taking a tiny tissue sample for DNA testing, and lots of photographs, they released her back into the water. The following year they found a second Shelta Cave crayfish.

The Shelta Cave crayfish is so little known that we don’t even know what it eats or how it survives in the same environment with two larger crayfish species. Biologist Dr. Matthew Niemiller is continuing Dr. Cooper’s initial studies of the cave and will hopefully be able to learn more about the crayfish and its environment.

Next let’s travel from a cool, damp, flooded cave in Alabama to northern Arizona. Arizona is in the western United States and this particular part of the state has desert-like conditions most of the year. Almost a thousand years ago, people built what is now called Wupatki Pueblo, a 100-room building with a ballcourt out front and a big community room. It was basically a really nice apartment building. Wupatki means “tall house” in the Hopi language, and while the pueblo people who built it are long gone, Wupatki is still an important place for the Hopi and other Native American tribes in the area. It’s also a national monument that has been studied and restored by archaeologists and is open to the public.

In late July 2021, torrential rain fell over the area, so much rain that it pooled into a shallow temporary lake around Wupatki, including flooding the ballcourt. The ballcourt is 105 feet across, or 32 meters, and surrounded by a low wall. One day while the ballcourt was still flooded, a tourist came up to the lead ranger, Lauren Carter. The visitor said there were tadpoles in the ballcourt.

There are toads in the area that live in burrows and only come out during the wet season when there’s rain, and Carter thought the tadpoles might be from the toads. She went to investigate, saw what looked like tadpoles swimming around, and scooped one up in her hands to take a closer look. But the tadpoles were definitely not larval toads. In fact, they kind of looked like teensy horseshoe crabs, with a rounded shield over the front of the body and a segmented abdomen and tail sticking out from behind, with two long, thin spines at the very end that are called caudal extensions. It had two pairs of antennae and lots of small legs underneath, some adapted for swimming. The largest of the creatures were about two inches long, or 5 cm.

What on earth were they, and where did they come from? This area is basically a desert. Carter stared at the weird little things and remembered hearing about something similar when she worked at the Petrified Forest National Park, also in Arizona. She looked the animal up and discovered what it was.

It’s called Triops and is in the order Notostraca. Notostracans are small crustaceans shaped sort of like tadpoles, which is why it’s sometimes called the tadpole shrimp, but it’s not a shrimp. It has two eyes on the top of its head visible through its flattened, smooth carapace. Species in the genus Triops also have a so-called third eye between the two ordinary eyes, although it’s a very simple eye that probably only detects light and dark. Many crustaceans have these third eyes in their larval forms but very few retain them into adulthood.

Notostracans have been around for about 365 million years, and haven’t changed much in the last 250 million years. It’s an omnivore that mostly lives on the bottom of freshwater pools and shallow lakes, often temporary ones like the flooded ballcourt, although some species live in brackish water and saline pools, or permanent waterways like peat bogs.

Triops eggs are able to tolerate high temperatures and dry conditions, with the eggs remaining viable for years or even decades in the sediment of dried-up ponds. When enough water collects, the eggs hatch and within 24 hours are miniature versions of the adult Triops. They grow up quickly, lay lots of eggs, and die within a few months or when the water dries up again.

Triops eggs are even sold as aquarium pets, since they’re so unusual looking and are easy to care for. They basically eat anything. They especially like mosquito larvae, so if you see some in your local pond or other waterway, give them a tiny high-five.

In 1996, some workers near Indianapolis, Indiana were servicing a tank full of chemical byproducts from making plastic auto parts when they noticed movement in the toxic goo. They investigated and saw several squid-like creatures swimming around. They were red-brown and about 8 inches long, or 20 cm, including their arms or tentacles, but were only about an inch wide, or 2.5 cm.

The workers managed to capture one and put it in a jar, which they stuck in the break room refrigerator. By the time someone in management arranged to have it examined by a scientist, the jar had been thrown out. If you’ve ever tried to keep food in a break room fridge, you’ll know that there’s always someone who will throw out everything in the fridge that isn’t theirs, no matter whether it’s labeled or brand new or not. I have had my day’s lunch thrown out that had only been in the fridge a few hours. Anyway, when the tank was cleaned out the following year, no one found any creatures in it at all.

This sounds really interesting, but there’s precious little information to go on. The story appeared in a few newspapers but we have no names of the people who reportedly saw the creatures, no follow-up information. It has all the hallmarks of a hoax or urban legend. The creatures’ size also seems quite large for extremophiles in a small, closed environment. What would they find to eat to get so big?

Next let’s talk about some mysterious tracks made by invertebrates, as far as we know. We’ll start with a track on land that was a mystery at first, but was solved. A man in the Kruger National Park in South Africa named Rudi Hulshof came across a weird track in the sandy dirt that he didn’t recognize. It was maybe 10 mm wide and kind of looked like a series of connected rectangles, as though a tiny person was moving a tiny cardboard box by rolling it over and over, but there weren’t any footprints, just the body track.

Curious, Hulshof followed the track to find what had made it, and finally discovered the culprit. It was a leech! Most leeches live in water, whether it’s the ocean, a pond or swamp, a river, or just flooded ground. Most species are parasitic worms that attach to other animals with suckers, then pierce the animal’s skin and suck its blood. The leech stays on the animal until it’s full, then drops off. Some leeches are terrestrial, but it appears that this one was a freshwater leech that had attached to an animal passing through the water, then dropped off onto land. It had crawled as far as it could trying to find a better environment, but when Hulshof found it it was dead, so it had not had a good day.

The leech moves on land by stretching the front of its body forward, then dragging its tail end up in a bunch kind of like a worm (it is a kind of worm), so that’s why its track was so unusual-looking. It’s a good thing Hulshof found the leech before something ate it, or else he’d probably still be wondering what had made that track.

We have photographs of other tracks that are still mysterious. You may have heard about one that’s been in the news lately. This one was found by a deep-sea rover in July 2022, more than a mile and a half deep, or 2500 meters, in the north Atlantic Ocean.

The track may or may not actually be a track, although it looks like one at first glance. It consists of a line of little holes in the seafloor, one after the other, although they’re not all the same distance apart. The rover saw them on two separate dives in different locations, so it wasn’t just one track, but although the scientists operating the rover remotely tried to look into the holes, they couldn’t get a good enough view. It does look like there’s sediment piled up next to the holes, so researchers think something might actually be digging the holes, either digging down from the surface to find food hidden in the sediment, or digging up from inside the sediment to find food in the water. The rover did manage to get a sample of sediment from next to one of the holes and a water sample from just above it, and eventually those samples will be tested for possible environmental DNA that might help solve the mystery.

This wasn’t the first time these holes have been seen in the area, though. An expedition in 2004 saw them and hypothesized that the holes are made by an invertebrate with a feeding appendage of some kind that it uses to dig for food. Not only that, we have similar-looking fossil holes in rocks formed from deep marine sediments millions of years ago.

Other deep-sea tracks have a known cause, and humans are responsible. In the 1970s and 1980s, ships with deep-sea dredging equipment traveled through parts of the Pacific Ocean, testing the ocean floor to see whether the minerals in and beneath the sediment were valuable for mining. A few years ago scientists revisited the same areas to see how the ecosystems impacted by test mining had responded.

The answer is, not well. Even after 40 years or so since the deep-sea mining equipment sampled the sea floor, the marks remain. The deep sea is a fragile ecosystem to start with, and any disturbance takes a long, long time to recover—possibly thousands of years. So while the holes discovered in 2022 were almost certainly made by an animal or animals, they might be quite old.

Let’s finish with a mystery animal we’ve talked about before, but a really long time ago—way back in episode 6. It’s definitely time to revisit it.

In 1883 when he was 18 years old, a Vietnamese man named Tran Van Con had seen the body of an enormous creature washed up on shore at Hongay in Vietnam. Van Con said it was probably 60 feet long, or 18 meters, but less than three wide wide, or 90 cm. It had dark brown plates on its back with long spines sticking out from them to either side, and the segment at its tail end had two more spines pointing straight back. It didn’t have a head, which had presumably already rotted off, or something bit it off before the animal washed ashore. It had been dead for a long time considering the smell. In fact, it smelled so terrible that locals finally towed it out to sea to get rid of it. It sank and that was the last anyone ever saw of it. The locals referred to it as a con rit, which means “millipede,” since the armor plates made it look like the segmented body of an immense millipede.

Lots of people have made suggestions as to what the con rit could be, but nothing really fits. It was the length of a whale, but it doesn’t sound like any kind of whale known. The armored plates supposedly rang like metal when hit with a stick. Even if this was an exaggeration, it probably meant the armor plates were really hard, not just the skin of a dead whale that had hardened in the sun. It also implies that the plates had empty space under them, allowing them to echo when hit. Zoologist Dr. Karl Shuker suggests that the plates might have been the exoskeleton of a crustacean of some kind, which makes a lot more sense than a whale, but the sheer size of the carcass is far larger than any crustacean, or even any arthropod, ever known.

There’s also some doubt that the story is accurate. It might even be a hoax. We only know about the con rit at all because the director of Indochina’s Oceanographic and Fisheries service, Dr. A. Krempf, talked to Tran Van Con about it in 1921. That was 38 years after Van Con said he saw the creature, so he might have misremembered details. Not only that, Krempf translated the story from Vietnamese, and there’s no way of knowing how accurate his translation was.

The con rit is also a monster from Vietnamese folktales, a sort of sea serpent that had lots of feet. It was supposed to attack fishing boats to eat the sailors, until a king caught it and chopped it up into pieces. A local mountain was supposedly formed from its head, and the other pieces of its body turned into the unusual stones found on a nearby island.

There’s always the possibility that Tran Van Con actually told Krempf this folktale, but that Krempf misunderstood and thought he was telling him something he actually witnessed. Then again, there are eight reports from ships in the area between 1893 and 1915 of creatures that might have been a con rit. One account from 1899 was a sighting of a creature estimated as being 135 feet long, or 41 meters, which was rowing itself along at the surface by means of multiple fins along its sides.

Whatever the con rit was, there haven’t been any sightings since 1915. That doesn’t mean there isn’t a population of incredibly long invertebrates living in the deep ocean in southeast Asia. If it does exist, maybe one day a deep-sea rover will spot one. Maybe it dug those little holes, who knows?

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 235: Deep-Sea Squid

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This week we visit the weirdest squid in the deep sea!

I was a guest on Tim Mendees’s After Hours that’s now up on YouTube! It’s mostly about my writing but we talk about all kinds of stuff, including cephalopods! There is some bad language but it’s not all that bad and it’s mostly toward the end.

Further reading/watching:

Elusive Long-Tailed Squid Captured on Film for First time

See Strange Squid Filmed in the Wild for the First Time (ram’s horn squid)

Multiple observations of Bigfin Squid (Magnapinna sp.) in the Great Australian Bight reveal distribution patterns, morphological characteristics, and rarely seen behaviour

Untangling the Long-Armed Mystery of the Bigfin Squid

Drawing of a long-arm squid and an actual long-arm squid:

Asperoteuthis mangoldae, which really should be called the long-tailed squid:

 

Verany’s long-armed squid, with its tentacles mostly retracted (so not looking very long-armed):

Verany’s long-armed squid with tentacles extended:

Drawing of a paralarval Verany’s long-armed squid:

The ram’s horn squid, floating along doop doop doop:

Drawing of the coiled internal shell of the ram’s horn squid:

A clawed armhook squid mama with her egg cluster:

Bigfin squid!

Another bigfin squid! Good grief look at that!

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

Before we get started, a quick announcement that I was a guest on a YouTube show called After Hours recently! I was there mostly to talk about my writing, but naturally animals came up too, especially cephalopods. There’s a link in the show notes if you want to watch the show. There is a little bad language, but not too bad and it’s more toward the end.

Anyway, in a not-exactly coincidence, this week we’re going to look at some of the weirdest deep-sea squids known. Yes, weirder than the flying squid we talked about in episode 101. We don’t know much about any of them, but they’re definitely not what you expect when you think about squid.

Let’s talk first about Asperoteuthis acanthoderma, the long-arm squid. It’s also sometimes called the thorny whiplash squid because it has little pointy tubercules in its skin and long, whiplike feeding tentacles. It lives in the deep sea and has been found in both the Pacific and the Atlantic Oceans, although very rarely. Despite its name, its feeding tentacles are much longer than its arms, although its arms are pretty long too. A squid’s body is generally more or less torpedo-shaped and is called a mantle. It has eight arms and two feeding tentacles that are usually longer than the arms. Many squid species have relatively short arms compared to mantle length.

The feeding tentacles in long-arm squid are very slender and delicate, and they’re easily broken off after the animal dies and has washed around in the water for a while. One intact specimen has been found and measured, though. It had a mantle length of almost a foot and a half long, or 45 cm, but its total length, including the tentacles, was 18 feet, or 5.5 meters. The tentacles were 12 times the mantle length.

Using that ratio, one large specimen found in 2007, which was 6 1/2 feet long, or 2 meters, including both mantle and arms, is estimated to have measured up to 24 feet long when it was alive, or over 7 meters. Most of its length is due to its incredibly long, thin feeding tentacles.

So what does the long-arm squid eat with those long, delicate tentacles? We don’t know. We don’t know most things about the long-arm squid.

Another species of Asperoteuthis is Asperoteuthis mangoldae. So little is known about it that it doesn’t even have an informal name. It was only described in 2007 and has only been found around the Hawaiian islands in the Pacific Ocean. It looks similar to the closely-related long-arm squid but without the incredibly long feeding tentacles. Instead, it has a sort of tail, so I nominate it to be called the long-tailed squid. It was caught on video for the first time in 2019 by a deep-sea rover. You’re going to hear a lot about deep-sea rovers in this episode. There are lots of links in the show notes to articles with embedded video of various squids, which is really interesting to watch.

Asperoteuthis mangoldae is a long, slender squid. I couldn’t find any measurements so it could be that’s just not known right now. The species in this genus have an extension of the mantle, on the side opposite of the arms, that looks like an extra fin but that doesn’t seem to be used as a fin. In the long-tailed squid, this extra fin is as long as its mantle and arms and feeding tentacles all measured together. Most of the time the thin flaps of skin on either side of the so-called tail are extended, making it look like a really long fin, but when the squid feels threatened and needs to flee, it collapses the fin part around the middle section so that it reduces drag in the water. That way the squid can move faster. Researchers speculate that the tail section may make the squid look much larger to potential predators, and possibly may imitate an organism called a siphonophore that has stinging cells.

Another squid called Verany’s long-armed squid is Chiroteuthis veranii. It’s related to the long-arm squid we talked about at the beginning of the episode, but they’re placed in different genera. It lives throughout the world’s oceans, often in the deep sea although not as deep as some of the species we’re talking about today. Unlike most squid, whose arms are all about the same length, two of its arms are much wider and longer than the others.

Like the other long-arm squid, its feeding tentacles are incredibly long and thin. The mantle is quite small, up to 8 inches long, or 20 cm, with the legs about the same length as or a little longer than the mantle, but the total length of this squid, including the feeding tentacles, is over four feet, or 130 centimeters. Most of the time the feeding tentacles are retracted, though, so they’re no longer than the arms, and they’re protected by the two largest arms. When the squid sees a tiny fish or crab or other small animal it wants to eat, it can shoot its retracted tentacles out at high speed to catch it. It’s probable that other species of long-armed squid hunt the same way.

A squid’s eggs hatch into an initial form called a paralarva. This is actually the case for other cephalopods too, including octopuses. The paralarvae usually just look like teeny-tiny miniature versions of the adult, but with stubby little arms. In the case of Verany’s long-armed squid, though, the larval squid looks sort of like a little rod. It’s long and thin, mostly transparent, and has a gladius, also called a pen, that sticks out the end of the mantle on the opposite side from the arms. The pen of a squid is named after an ink pen, although the other name, gladius, refers to the shape of a type of ancient Roman sword. It’s a vestigial shell but located inside the squid’s body. The tail of the long-tailed squid we just talked about is given structure by the gladius, so it’s possible that its paralarvae look rod-like, like those of Verany’s long-armed squid.

Speaking of internal shells, the ram’s horn squid has a coiled internal shell. This is unique among all the squid known to be alive today, so the ram’s horn squid is the only living member of its own order and its own family and its own genus. Technically it’s not really considered a squid although it is a closely related cephalopod. It’s small, with a mantle length only about an inch and a half long, or 4.5 centimeters. Its eight arms are quite short and it has two feeding tentacles that are about the same length as its mantle. Its mantle has an outer covering that extends down almost to the squid’s eyes, and it’s big enough that the squid can pull its eyes and legs and tentacles under this covering. The spiral shell resembles that of a nautilus, but it’s inside the squid instead of the nautilus living inside the shell. The shell contains gas that the squid uses to adjust its buoyancy.

For a long time researchers were confused as to how the ram’s horn squid oriented itself in the water. The empty shells from dead squid wash ashore pretty often, and experiments with them show that they want to float with the big end of the shell pointing downward. That confused the researchers, since that would mean the squid floats around with its arms downward too, which means that the photophore on the tail end of its mantle points upward. A photophore is a light-emitting organ, which is common in deep-sea animals. Usually an animal wants its light to point downwards, which means that larger animals looking up toward the surface see a little light sparkling amid the light shining down from the surface instead of seeing a squid-shaped shadow against the surface.

Then, in late 2020, a deep-sea rover exploring the northern section of the Great Barrier Reef off the coast of Australia got a video of a ram’s horn squid in the water. It was the first time a living one had ever been observed. In the video, the squid is floating with its arms pointing upward, flapping the fins on its mantle to move along in the water. Mystery solved! There’s still a lot we don’t know about the ram’s horn squid, but at least we know it doesn’t swim around upside-down.

Another squid that has only recently been seen alive in the wild from a deep-sea rover is the clawed armhook squid. My brother Richard alerted me to this one in a Twitter thread. The clawed armhook squid lives in the northern Pacific Ocean and has a mantle length of about seven inches, or 18 cm. Its arms are about the same length as its mantle. It gets its name from the female, which has small hooks on her arms to help her keep hold of her egg cluster. She lays about 3,000 eggs in a tube-like cluster that looks sort of like a gray cloth bag that’s open at both ends. Most squid lay their eggs on the sea floor and leave them, usually dying soon after, but the clawed armhook squid holds her egg cluster until the eggs hatch. She makes sure the eggs get enough oxygenated water by pumping water through the middle of the bag. She also swims away from anything that might want to eat her eggs or her, although she can’t swim very fast since she has to use her arms to hold onto the egg cluster. She usually stays in deep water far from shore while the eggs are developing, because there are fewer predators there than in her usual habitat nearer shore. In 2001 a rover spotted a mother squid with her egg cluster at 8,200 feet below the surface, or 2500 meters. That’s more than a mile and a half down, or two and a half kilometers.

Unfortunately for the mother squid, after she lays her eggs, she can’t use her arms for anything except holding and taking care of them, and that includes eating. She just doesn’t eat once she lays her eggs, and while we’re not sure how long it takes for them to hatch, it may be as much as nine months. It’s most likely that she dies after her babies hatch. All the female squids seen with egg clusters have been missing their feeding tentacles, and researchers think the squid may actually bite off her own tentacles so they don’t get in the way of her eggs.

Finally, the family Magnapinnidae, also called bigfin squids, were mysteries for over a century. For a long time they were only known from paralarval and juvenile individuals. Five species are known but there may be more, but no scientist has ever been able to study an adult except through photographs and videos made by deep-sea rovers.

All squid have fins of some kind on the mantle to help it move around. Different species, naturally, have varying sizes and shapes of fins. In the bigfin squid, as you may have guessed, the fins are very big. They look more like wings and can be almost as large as the entire mantle. But that’s not the really weird thing about these squid, although it was the most obvious thing when all we knew about them were young specimens. The arms and tentacles of squid don’t develop to their full length until the squid is an adult. The bigfin squid’s arms and tentacles are very long and they’re also very different from all other squids.

In 2001, a deep-sea rover used by an oil company in the Gulf of Mexico caught video of a large, unusual squid. Fortunately, one of the men operating the rover remotely asked for a copy of the squid video for his girlfriend, who was interested in deep-sea animals. His girlfriend asked around, trying to find out what kind of squid it was, and eventually contacted a squid expert at the Smithsonian National Museum of Natural History. The squid expert is named Mike Vecchione and when he saw the video, he freaked out. He’d never seen anything like this squid before. He says he jumped out of his chair and started yelling in excitement.

Then, once he calmed down, he contacted all his squid expert colleagues, who also freaked out, and eventually they found more footage of the weird squid taken by other oil rig rovers. The workers operating the rovers had no idea that the squid was a scientific mystery so hadn’t thought to contact any scientists. Finally the squid was identified as an adult bigfin.

In 2015, a deep-sea rover in a scientific expedition caught video of two bigfin squid near Australia, and in 2017 it saw three more. It also spotted some juvenile bigfin squid in the same area. Even better, the rover was able to use lasers to get a much more accurate estimate of the squid’s size than ever before. All five were different sizes, so they were probably five different individuals.

The bigfin squid has very thin arms and tentacles, referred to as vermiform. That means worm-shaped, which gives you an idea of how thin we’re talking. The largest bigfin squid measured by the rover in 2015 and 2017 had a mantle length of about 6 inches, or 15 cm, and a fin width of 5.5inches, or 14 cm, but the longest arm or tentacle length was 5.5 feet, or 1.68 meters. Measurements of other bigfin squid suggest it can grow up to 26 feet long, or 8 meters, and maybe even longer.

In the bigfin squid, the arms and tentacles are the same size. In other squids, the tentacles are usually longer and look different from the arms. The great length of the arms and tentacles of the bigfin squid comes from what’s called a distal filament that grows from the tip of the arm or tentacle. The filaments are sometimes missing, so it’s possible that they’re sometimes damaged and lost or maybe bitten off. The squid seems to use its arms and tentacles the same way instead of using its arms for some things and its tentacles for other things.

The bigfin squid holds its arms and tentacles differently from any other squid, in what’s called a crane pose or elbow pose. It’s not clear from the articles I read, but it seems to be that if you don’t count the distal filaments, the arms and tentacles are not actually all that long in comparison to its mantle. When it’s hunting, the squid holds them out from its body with the extremely long filaments hanging down. It looks like the squid has elbows that way. Squid don’t have elbows because squid, like other cephalopods like octopuses, don’t have any bones. We talked about how octopuses move without bones in episode 142 if you’re interested, and it’s the same for squid.

The bigfin squid can retract the filaments by coiling them up. One researcher said the coiled-up filaments look sort of like an old-fashioned phone cord, which will mean nothing to my younger listeners but the rest of us just thought, “Oh yeah, that makes total sense.” The filaments are sticky and trap tiny animals and particles of food drifting in the water. If you remember way way way back in episode 11 where we talked about the vampire squid, it uses its feeding tentacles the same way, including being able to retract them, but the vampire squid and the bigfin squid are not very closely related at all.

A research sub investigating a WWII shipwreck spotted a bigfin squid 3.7 miles below the surface, or 6,000 meters, which made it the deepest squid ever recorded. Imagine looking out the window of a submarine, assuming they have windows, trying to see details of a shipwreck, and suddenly there’s a massive squid with incredibly long, thin arms looking back at you.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us that way.

Thanks for listening!

Episode 231: Fish of the Twilight Zone

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Let’s learn about some strange fish of the mesopelagic, or the twilight zone deep in the ocean! Thanks to Page, Joel, Anonymous Animal Lover, Brigham, and Fireburster for suggestions this week!

Further reading:

In Defense of the Blobfish

Further viewing:

Pacific viperfish (video embedded)

The Pacific viperfish, head-on (or rather teeth-on), still from video linked above:

Sloane’s viperfish, rocking those teeth:

The blobfish as it’s usually seen on the internet:

The blobfish as it looks when it’s cozy in its deep-sea environment:

The barreleye, which I have helpfully labeled for you:

Look at the bristlemouth’s sharp thin teeth! Good thing it’s only a few inches long:

An indignant bristlemouth (someone should take MS Paint away from me):

The bristlemouth is the most abundant vertebrate in the WORLD (photo by Paul Caiger):

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

Where on earth does the time go? Suddenly we’re halfway through 2021 and I’m still vaguely thinking we’re only a few months in. I’m getting seriously behind on listener suggestions, so let’s have an episode about some weird fish that’s all listener suggestions. Thanks to Page, Joel, an animal lover who wants to remain anonymous, Brigham (whose name I hope I’m pronouncing correctly), and someone who calls themself Fireburster. Fireburster and Anonymous Animal Lover also both left us really nice reviews, so thank you! I picked all these suggestions at random, just grabbing fish suggestions that sounded interesting, but the great thing is they all turned out to live in a specific part of the deep sea.

Brigham and Fireburster both suggested the same fish, so let’s start with that one: the dragon fish. Neither of them specified which kind of dragon fish they’re talking about, though. It’s a popular name for weird fish of various kinds. We’ve even talked about a few before, the Pacific blackdragon of episode 193, which was coincidentally suggested by Page, and the barbeled dragonfish in that same episode. That’s the episode about William Beebe’s mystery fish, which happens to be my current favorite.

We only talked about the barbeled dragonfish briefly before, so let’s learn more about them now.

The barbeled dragonfish gets its name from the filament that hangs down from its chin, called a barbel. If you’ve ever wondered what the proper name for a catfish’s whiskers is, they’re also barbels. The dragonfish’s barbel has a photophore at the end that produces blue-green bioluminescent light, and the fish flashes the light to attract prey. Its head is large and its jaws are full of sharp teeth, so when an animal comes close, CHOMP! The barbeled dragonfish grabs it.

The dragonfish isn’t very big, with the blackdragon that we talked about in episode 193 being the largest at only 16 inches long, or 40 cm. Most species are about half that. So what happens when an animal the same size as or even bigger than the dragonfish happens along?

The dragonfish eats it, that’s what happens. It has large jaws that it can unhinge to swallow prey that’s bigger than it is, and its stomach can expand considerably to hold whatever it swallows. Mostly it just eats tiny animals like krill and amphipods, though.

We don’t know a whole lot about dragonfish. Various species live throughout most of the world’s oceans, especially in tropical and subtropical areas, and they don’t live in the deepest parts of the ocean. Instead, they’re found in what’s called the twilight zone, or more properly the mesopelagic. Only 1% of all light shining down from the surface makes it down this far, which is why so many animals produce their own bioluminescent light. The dragonfish also has photophores along its sides that it can flash to help attract prey or attract mates. On nights when the moon isn’t too bright, the dragonfish will migrate closer to the surface to find more food, but it makes sure to go back to the twilight zone before the sun rises.

[twilight zone music]

One genus of dragonfish is called the viperfish, and they’re a little different from other dragonfish. Instead of a barbel on the chin, viperfish have a light at the end of a long spine that’s a modified dorsal fin. This is similar to the anglerfish we’ve talked about many times before, even though dragonfish and anglerfish aren’t related. Convergent evolution, at it again!

The viperfish has teeth so long they don’t fit in its mouth. Instead, they stick out, which gives it its other name of fangfish. Sloane’s viperfish has the largest teeth of all the viperfish species, so long that they form a cage across its mouth to stop prey from escaping before the fish can swallow it. Unlike most dragonfish, Sloane’s viperfish sometimes swims toward its prey very quickly, slamming into it and wounding it with its fangs. It even has a sort of built-in shock absorber in its spine right behind its head. The Pacific viperfish can also be aggressive when hunting.

This is probably a good place to learn a little more about the twilight zone, AKA the mesopelagic. It’s measured not by depth but by how much light is available from the surface, in this case only 1% of light. There’s also not as much oxygen in the water here as at the surface. Many, if not most, animals that live in the mesopelagic migrate closer to the surface at night to find food, then retreat to the darkness below to avoid being seen as the sun rises and fills the upper layers of water with more light.

Lots and lots of animals live in the mesopelagic, from giant squid to oarfish, although most of the animals here are small. Below this layer of water is the bathypelagic, and below that is the real depths, the abyssopelagic where conditions are extreme and life gets really weird and scarce. The uppermost layer of the ocean is called epipelagic, if you were wondering. No plants live in the mesopelagic or below, because there’s not enough light. Obviously, the ocean isn’t always deep enough to have a bathypelagic layer or below, and quite often the mesopelagic ends at the sea floor.

It’s hard to study mesopelagic animals because many of them can’t survive at the surface. They’re built to withstand the increased water pressure at depths up to 3,300 feet, or 1000 meters, below the surface, and when they’re dragged up in nets they often die within minutes. Many marine animals have an organ called a swim bladder that’s filled with gases, which helps the animal stay neutrally buoyant in the water so it doesn’t float upward or sink downward when it’s not moving. The animal can adjust the amount of gas in its bladder as it swims upward, but when it’s pulled upward quickly in a net it can’t expel enough gas fast enough and the swim bladder can burst or expand so much that it squishes the rest of its insides, killing the animal before it even reaches the surface. Animals that don’t migrate vertically often don’t have a swim bladder since they don’t need it, and they’re just adapted for water pressure that’s as much as 120 times greater than pressure at the surface. This pressure difference is why blobfish look so blobby, so let’s talk about the blobfish next, Anonymous’s suggestion.

The blobfish lives on the sea floor in deep water near Australia and New Zealand. It grows about a foot long at most, or 30 cm, and is grayish with little spikes all over it. It has a gelatinous body with weak muscles and a weak skeleton, but it doesn’t need either since the intense pressure of the water presses in around the fish all the time and keeps it just the way it should be. It looks like a fish. Its gelatinous flesh is slightly less dense than the water around it, which means it can float just above the sea floor without much effort, just drifting along, giving its tail and broad fins a little flap every so often. It eats whatever detritus floats down from far above, although it’s also mostly on the lookout for small crustaceans that live on the sea floor.

The problem comes when a fishing net catches a blobfish and brings it to the surface. Suddenly there’s no nice firm water around the fish. Instead of being slightly less dense than the water around it, the blobfish is suddenly way more dense than the water, and it expands as a result. Then someone looks at this horrible dead pinkish blob that was once a happy live fish and thinks, “Gross! I’ll take a picture of that for the internet,” and that’s why the blobfish gets its name. Poor blobfish!

Fortunately, scientists have developed a compression chamber for the animals they study. When a deep-sea animal is put in the compression chamber and brought to the surface, the compression chamber keeps the water pressure where the animal needs it. The animal doesn’t die horribly, and that allows researchers to observe a live animal instead of a dead blobby one.

Next, let’s learn about Page’s suggestion, the barreleye fish. It lives in the North Pacific in deep water, and it has upward-pointing eyes that are very sensitive to light. It’s a small fish, only about six inches long, or 15 cm, and is mostly dark in color, as you would expect from a deep-sea fish. It’s chonky in shape with large fins that help it stay motionless in the water while it looks for tiny fish and jellyfish silhouetted against the water’s surface far above. Then the barreleye will move quickly to grab its prey.

It seems like there’s something I’m forgetting to tell you. Hmm. There’s something unusual about the barreleye fish, I just know it.

Oh yeah. The domed top of its head is transparent and its eyeballs are inside the dome. You can see the internal eyeballs and its brain through its transparent head, which is otherwise filled with liquid. It is really weird-looking. Its eyes are tubular, which gives it its name, and they can rotate around to focus on things or look straight ahead when it wants to. The eyes also have bright green lenses, which helps filter out the faint sunlight from above so the fish can better see the bioluminescent glow of other deep-sea animals.

It wasn’t until 2004 that researchers realized the barreleye’s eyes were covered by the transparent dome, because it’s fragile and would end up destroyed when a fish was dragged up by nets. The first photographs and video of the barreleye in its natural environment, taken by deep-sea remote vehicles, must have freaked the researchers out completely.

If you’re wondering why the barreleye has its eyeballs hidden inside a transparent dome, researchers have wondered that too. The best guess is that the dome protects the large, sensitive eyes from jellyfish stings, since barreleyes love to eat jellyfish.

Finally, Joel suggested the bristlemouth fish. The bristlemouth is a small, slender fish that generally grows no longer than a person’s finger, although one species grows up to 14 inches long, or 36 cm. Males are smaller than females. It lives throughout the world’s oceans and is black or dark brown to hide it in the twilight zone where it lives. Like the barbeled dragonfish, which by the way really likes to eat it, it migrates closer to the surface at night to find food, then goes deeper again in the daytime to hide in the darkness.

The bristlemouth gets its name from its teeth, as you may have guessed. It has a large mouth lined with lots of short, thin teeth. It mostly eats small crustaceans, especially copepods, but will also grab tiny fish and other animals. Its lower jaw is longer than its upper jaw and can open wide to grab animals larger than it is. Unlike the other fish we’ve talked about today, its eyes are small and it doesn’t use them to find prey. Instead, it uses its lateral line system, which allows it to detect tiny movements in the water. The male bristlemouth also has a good sense of smell to help it find a female. All bristlemouths start out life as male, but some males metamorphose into females as they age.

The bristlemouth also has rows of light-emitting photophores on its underside to help hide it from predators. Its photophores glow to match the amount of light shining down from far above, which means its silhouette is much harder to see by fish or other animals below it.

There’s still a lot we don’t know about the bristlemouth, but we do know one thing. It’s the most abundant fish in the ocean. Literally there are more bristlemouths in the world than any other vertebrate, estimated at hundreds of trillions of them, possibly as many as a quadrillion, which is a million billion. That’s a lot of fish. There are so many that Navy sonar bounces off them and looks like a false bottom of the ocean. The United States Navy calls it the Deep Scattering Layer and wasn’t sure what was causing it, but the mystery was solved in 2010 when a research vessel with fine-mesh nets kept bringing up unbelievable numbers of the tiny fish. Specifically, the abundant ones are bristlemouth fish in the genus Cyclothone, which mostly lives in tropical areas.

The first person to see a bristlemouth in its natural habitat was William Beebe in the 1930s, during a bathysphere descent into the twilight zone, which brings us right back to where we started this episode.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us that way, and don’t forget to join our mailing list. There’s a link in the show notes.

Thanks for listening!

Episode 193: Beebe’s Mystery Deep-Sea Fish

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This week we’ll learn about five mystery fish that William Beebe spotted from his bathysphere in the early 1930s…and which have never been seen again. Thanks to Page for suggesting deep-sea fish!

Further reading:

How some superblack fish disappear into the darkness of the deep sea

The Fine Art of Exploration

Further listening:

99% Invisible “Bathysphere”

The Gulper Eel unlocked patreon episode

These two guys crammed themselves into that little bathysphere together. Sometimes they got seasick and puked in there. Also, they didn’t like each other very much:

The Pacific blackdragon is hard to photograph because it’s SUPERBLACK:

A larval blackdragon. Those eyestalks!

A painting (by Else Bostelmann) of Bathysphaera intacta (left) and an illustration from Beebe’s book Half Mile Down:

The pallid sailfish, also painted by Bostelmann:

A (dead) stoplight loosejaw. Tear your surprised eyeballs away from its weird jaws and compare its tail to the pallid sailfish’s:

A model of a loosejaw (taken from this site) to give you a better idea of what it looks like when alive. Close-up of the extraordinary jaws (seen from underneath) is on the right:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week we’re going to descend metaphorically into the depths of the ocean and learn about some mystery fish spotted once from a bathysphere by famous naturalist William Beebe and never seen again. Deep-sea fish is a suggestion by Page, so thank you, Page, for a fascinating and creepy addition to monster month.

William Beebe was an American naturalist born in 1877 who lived until 1962, which is amazing considering he made repeated dives into the deep sea in the very first bathysphere in the early 1930s. We talked about bathyspheres way back in episode 27–you know, the one where I scream about them imploding and kind of freak out a little. Even today descending into the deep sea is dangerous, and a hundred years ago it was way way way more dangerous.

Beebe was an early conservationist who urged other scientists to stop shooting so many animals. Back then if you wanted to study an animal, you just went out and killed as many of them as you could find. Beebe pointed out the obvious, that this was wasteful and didn’t provide nearly as much information as careful observation of living animals in the wild. He also pioneered the study of ecosystems, how animals fit into their environment and interact with it and each other.

While Beebe mostly studied birds, he was also interested in underwater animals. Really, he seems to have been interested in everything. He studied birds all over the world, was a good taxidermist, and especially liked to study ocean life by dredging small animals up from the bottom and examining them. He survived a plane crash, was nearly killed by an erupting volcano he was observing, and fought in WWI. Once when he broke his leg during an expedition and had to remain immobilized, he had his bed carried outside every day so he could make observations of the local animals as they grew used to his presence.

In the 1920s, during an expedition to the Galapagos Islands, he started studying marine animals more closely. First he just dangled from a rope over the surface of the ocean, which was attached to a ship’s boom, but eventually he tried using a diving helmet. This was so successful that he started thinking about building a vessel that could withstand the pressures of the deep sea.

With the help of engineer Otis Barton, the world’s first bathysphere was invented and Barton and Beebe conducted dozens of descents in Bermuda, especially off the coast of Nonsuch Island. The bathysphere had two little windows and a single light that shone through one of the windows, illuminating the outside just enough to see fish and other animals. The bathysphere couldn’t descend all that deeply, although it set records repeatedly. The deepest they descended was 3,028 feet, or 923 meters, but Beebe made careful notes of all the animals he observed and published many articles and books about them. Many of these articles and books were illustrated by an artist named Else Bostelmann, who worked closely with Beebe and his team of scientists. Bostelmann even painted underwater while wearing a diving helmet, because she needed to know how colors were affected by underwater light. She used oil paints, since oil and water don’t mix so the paints wouldn’t wash away, and she tied strings to her paintbrushes so they wouldn’t float off.

Incidentally, if you’re interested in reading a really interesting article about Bostelmann or learning more about the bathysphere and William Beebe, check the show notes. I’ve included links to the article and to a 99% Invisible episode about the bathysphere.

Many of the animals Beebe saw from the bathysphere have since been identified and described by later scientists. But there are five fish that Beebe observed that have never been seen since.

Before we talk about them, let’s learn about Page’s suggestion, the Pacific blackdragon, for reasons that will shortly become clear. The Pacific blackdragon is a type of fish that lives in the Pacific, which you probably figured out without me telling you. It prefers tropical and temperate water, although since it’s a deep-sea fish the water where it lives is mostly very cold.

If you remember episode 155 about extreme sexual dimorphism, where the males and females of a species look radically different, this fish is a good example. The male never eats. He can’t eat. He doesn’t have a functioning digestive system. He survives on the yolk from the egg he develops from and never grows any larger than his larval form, about three inches long, or 8 cm. He lives long enough to mate and then he dies.

The female, however, grows up to about two feet long, or 61 cm. Her body is long and thin, and her mouth is full of sharp teeth that she uses to grab anything she can catch. She especially likes to eat fish and small crustaceans, but she’s not picky.

Her body is black, and not just regular black. It’s called superblack or ultrablack. In episode 186 we talked about the eyed click beetle and velvet asity who both have superblack markings that absorb most of the light that hits them. Well, the Pacific blackdragon is superblack almost all over to help hide in the darkness of the water, since it’s an ambush predator. Just under the fish’s skin, there’s a layer of closely packed pigment-containing structures called melanosomes, which can absorb up to 99.95% of light. As if that wasn’t enough, because a lot of the animals the blackdragon eats emit bioluminescent light, her stomach is also black to block any light from the prey she’s swallowed. But although she’s basically invisible to other animals, she does have several rows of light-emitting cells called photophores along her sides. Scientists think she uses the lights to attract a mate, but she only flashes the photophores occasionally and only for brief moments. She also has a barbel that hangs from her chin with a luminescent lure at the end, which she uses to attract prey.

While the Pacific blackdragon is a deep-sea fish, at night she migrates upward nearer the surface to catch more prey, although she still stays below about 1,300 feet deep, or 400 m. She has large eyes as a result to take advantage of any moonlight and starlight that shines down that far. During the day she stays deeper, up to 3,200 feet deep, or 1,000 m.

Speaking of the Pacific blackdragon’s eyes, larval blackdragons have eyes on long stalks—really long stalks, nearly half their body length. As the larva matures, it absorbs the stalks until the adult fish has ordinary fish eyes. The larvae are also mostly transparent.

There are two other blackdragon species known, both of them a little smaller than the Pacific blackdragon. But in 1932 William Beebe spotted a fish that he thought might be related to the blackdragons, except that he estimated it was six feet long, or 1.8 m.

Beebe named the fish Bathysphaera intacta, but there’s no type specimen so no one can study it and verify whether it’s a species of blackdragon or something else. Beebe said the fish he saw had large eyes, lots of teeth, and photophores along its sides that glowed blue, and had a barbel with a light under its chin just like the Pacific blackdragon and its cousins. But it also had another, smaller barbel with a light near the tail. Beebe saw two of the fish together. They circled the bathysphere a few times, probably attracted to its light.

Another of Beebe’s mystery fish is one he named the pallid sailfin, Bathyembryx istiophasma. He saw it twice on the same descent in 1934, and described it as about two feet long, or 61 cm, shaped like a cigar with triangular fins and a tiny tail. In fact, in his book Half Mile Down Beebe described the fish this way:

“The strange fish was at least two feet in length, wholly without lights or luminosity, with a small eye and good-sized mouth. Later, when it shifted a little backwards I saw a long, rather wide, but evidently filamentous pectoral fin. The two most unusual things were first, the color, which, in the light, was an unpleasant pale olivedrab, the hue of water-soaked flesh, an unhealthy buff. It was a color worthy of these black depths, like the sickly sprouts of plants in a cellar. Another strange thing was its almost tailless condition, the caudal fin being reduced to a tiny knob or button, while the vertical fins, taking its place, rose high above and stretched far beneath the body, these fins also being colorless.”

Beebe assigned the pallid sailfish into the family Stomiidae, the same family that Bathysphaera intacta is assigned to as well as the other blackdragons. As a group, the fish in this family are called barbeled dragonfish. Some species in this family do show a similar tail arrangement that Beebe noted, with a very small tail fin but enlarged anal and dorsal fins that are set well back on the body. This includes a weird fish with various names, including black hinge-head, black loosejaw, or lightless loosejaw, which maybe gives you an idea of what it looks like. It’s a deep-sea fish like all the barbeled dragonfish, and it’s black in color. It grows about 10 inches long, or almost 26 cm. It’s also sometimes called the stoplight loosejaw because it has two photophores on its head, one of which shines green, the other which shines red. Unlike most deep-sea fish, it can see in the red spectrum, so the green photophore may attract prey and the red photophore allows the loosejaw to see its prey even though the prey can’t see the loosejaw. But mainly, it has remarkable jaws.

The loosejaw’s jaws are hinged and extremely large compared to the body, which is fairly thin. The jaws are so large that they’re not even attached to its body, just to its head. They aren’t even connected to the body with skin. It’s hard to describe, but I have some good pictures of a model of the fish in the show notes. Basically, the jaws are just bones covered with a thin layer of skin, but no skin or muscle in between the bones. If you put your thumb under your chin, you can feel your chin bone, then move your thumb backwards and instead of bone, you feel skin over layers of fat and muscle and other tissues that make up the soft part of your jaw. Well, the loosejaw doesn’t have those soft parts. It just has the chin bone and there’s literally nothing between the jaws. It doesn’t have a throat or cheeks or anything like that. Its jaws aren’t big because it needs to swallow big things, its jaws are big so it has a longer reach to snag the small fish and crustaceans it eats. It has a lot of needlelike teeth that it uses to keep its prey from wriggling away while it maneuvers it into its gullet. It mostly eats very small animals, but it’s not going to let anything get away once it gets within jaw range.

While I was researching this episode, I spent a ridiculous amount of time trying to find the episode where I talked about the umbrellafish, thinking it might be related to the loosejaw. It’s not, and I finally realized the umbrellafish episode was for patrons. I’ve unlocked that Patreon episode and linked to it in the show notes if you want to go listen to it. The umbrellafish, also called the gulper eel, looks superficially like the loosejaw, but it has skin over its huge hinged jaws.

After my inability to properly describe the loosejaw’s amazing jaws, let’s move on to Beebe’s other mystery fish. One he named the three-starred anglerfish, Bathyceratias trilychnus, which he estimated was about six inches long, or 15 cm. It had three bioluminescent illicia on its head that it probably used as lures, since that’s something that other deep-sea anglerfish do and Beebe was pretty sure it was actually a species of anglerfish. Since there are over 200 known species of anglerfish, it’s not surprising that there are more that aren’t known.

Another was the five-lined constellation fish, Bathysidus pentagrammus, named for the five rows of photophores on its sides. Beebe thought it looked kind of like a surgeonfish, which is a flat, round fish shaped sort of like a pancake with fins and a tail. But surgeonfish are mostly found in shallow, tropical waters around coral reefs. They’re often brightly colored. Beebe didn’t assign his constellation fish to the surgeonfish’s family, and in fact didn’t assign it to any family since he didn’t know where it belonged.

The last of Beebe’s mystery fish was the rainbow gar, which he didn’t give a scientific name to since he had no idea what kind of fish it might be. He thought it was shaped like a gar, but it was so extraordinary he didn’t know what to think. He actually saw four of them swimming almost vertically, heads up and tails down, at about 2,500 feet deep, or 760 m. He named them rainbow gar because of their coloring: bright red head and jaws, a light blue body, and a yellow tail. They were about four inches long, or a little over 10 cm, with long, pointed jaws. They moved by fanning the dorsal fin, sort of like a seahorse.

Beebe wrote scientific articles about some of these fish and included them all in his book Half Mile Down. But it wasn’t long before other scientists started doubting the sightings. Some people thought he’d made up the fish to make his expeditions more exciting, some thought he was just mistaken. One irate ichthyologist wrote in 1933 that the constellation fish was probably just light reflecting off Beebe’s own breath fogging the window, because no fish had photophores like the ones he described. Because I guess in 1933 everything was known about fish that would ever be known, right?

Beebe seems to have been an honest scientist, though, and he didn’t really need to make anything up. He discovered dozens, if not hundreds, of fish new to science, many of which have either been found and properly described later, or which Beebe himself managed to later catch. Whenever he and Barton came up from a descent in the bathysphere, Beebe had his team on the boat send down nets, and sometimes they caught some of the animals he had seen. This allowed Bostelmann to add details to her paintings that Beebe wouldn’t have known about from just a look through the bathysphere’s windows.

Not only that, if Beebe wanted to make up a fish that would excite the general public and make them want to buy his books, he would have made up something huge and frightening. His mystery fish are mostly quite small. Only Bathysphaera intacta was large, and he only said they were about six feet long. That’s big for a deep-sea fish, but remember that the bathysphere never made it to the really crushing depths of the abyss. It descended into the mesopelagic zone, which is extremely dark but not completely lightless. There’s also a lot of life in this zone, and many fish that spend the day here migrate nearer the surface at night where they can find more food while still remaining hidden. The long-snouted lancetfish lives in this zone and it can grow seven feet long, or 2.15 m.

Plus, Beebe didn’t need to convince anyone to buy his books. They were already runaway bestsellers and he was quite famous, although it seems not to have gone to his head. He just wanted to have fun and do science. He actually seems to have been a good person by modern standards too, which is always refreshing. He disagreed with people who claimed to have scientific proof that women were inferior to men or that some races were inferior to others. He insisted that his team members work hard, but he worked hard too, and if he thought everyone was feeling too stressed, he’d announce that his birthday was coming up and they should take a few days off to celebrate. Some years he had several birthdays.

Beebe did spot one other mystery animal, but he didn’t get a good enough view to make a guess as to what it might be. This is what he wrote about it:

“…I saw its complete, shadow-like contour as it passed through the farthest end of the beam [of light]. Twenty feet is the least possible estimate I can give to its full length, and it was deep in proportion. The whole fish was monochrome, and I could not see even an eye or a fin. For the majority of the ‘size-conscious’ human race this marine monster would, I suppose, be the supreme sight of the expedition. In shape it was a deep oval, it swam without evident effort, and it did not return. That is all I can contribute, and while its unusual size so excited me that for several hundred feet I kept keenly on the lookout for hints of the same or other large fish, I soon forgot it in the (very literal) light of smaller, but more distinct and interesting organisms.

“What this great creature was I cannot say. A first, and most reasonable guess would be a small whale or blackfish. …[O]r, less likely, it may have been a whale shark, which is known to reach a length of forty feet. Whatever it was, it appeared and vanished so unexpectedly and showed so dimly that it was quite unidentifiable except as a large, living creature.”

Twenty feet is six meters, by the way. It might easily have been a whale, since many species of whale routinely dive much farther than the bathysphere descended at its deepest. Whatever it was, and whatever Beebe’s other five mystery fish were, hopefully one day a modern deep-sea vehicle will find them again.

You can find Strange Animals Podcast online at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us that way. Don’t forget to enter our book giveaway if you haven’t already, too! Details are on the website.

Thanks for listening!