Freaky Freshwater Giants: Vampire Fish, Giant Salamanders, and More

Dive into the mysterious world of freshwater ecosystems with Wildly Curious! In this episode, Katy Reiss and Laura Fawks Lapole uncover some of the strangest and most fascinating creatures lurking in rivers and lakes worldwide. From the razor-toothed vampire fish of the Amazon to the ancient Chinese giant salamander, and even the armored Arapaima of the Amazon River Basin, each bizarre species has evolved incredible adaptations for survival. With a mix of humor and deep dives into science, this episode reveals why freshwater ecosystems are home to some of the most freaky and fascinating creatures on Earth. 

Whether you’re a nature enthusiast, science buff, or just curious about the weird wonders of water, this episode has something for everyone!

Transcript

Laura: [00:00:00] hello and welcome to Wildly Curious. A podcast that tells you everything you need to know about nature. And probably more than you wanted to know. I'm Lara.

Katy: I'm Katy and today we're going to dive into the world of freshwater ecosystems, which is home to some of the weirdest and I would think most unbelievable creatures you've probably never have heard of. 

Laura: Dive in. Yeah. I 

Katy: that pun? But um. But we're going to be talking about, I don't want to say freaks of freshwater or freshwater freaks, but that's pretty much, we're going to talk about

things that you can find in freshwater that are just, I 

don't

think talked

about enough.

Just like the 

bizarro 

Laura: And we're not

talking like cryptids, cause we've done that. Right? like real things. 

Katy: real things. Real live things. 

I,

don't have any nature 

news.

Okay. 

Okay. 

Laura: I don't, I, I have an update. Someone reached out to me after our, , food safety episode that we did right before Christmas. And, the, they wrote to me saying, hey, just FYI, cause we talked about [00:01:00] how, when hamburgers all chopped up, more bacteria is introduced because of the amount of slices, right?

We all know that. I was told that BTW, Costco tenderizes all of their steaks before they put them in the packages, which means they stab them a lot with a fork, which means you cannot just sear a Costco steak, you should be cooking it through because of meat tenderizing. 

Katy: Interesting. 

And

clearly

Costco 

Laura: love Costco. I fully support you, Costco.

But,

Katy: And your foot long hot dogs.

But, 

Laura: yeah, 

Katy: they can't be the 

Laura: yeah, I love Costco. 

Katy: There's no way 

Laura: No, probably not. But yeah, 

I guess if you're, if you're, 

if you like a steak like I do, which is still pretty red, like medium rare, 

definitely, then make sure it's not being

tenderized first, if you can try and find that 

Katy: Just try to find the non 

thunderized 

meat. 

Yeah. 

Laura: have you pounded this 

meat? 

Katy: you tenderized your meat

today? 

Wow, this is [00:02:00] the first episode of season 

11. We're

gonna 

Laura: talking about pounding

meat. I'm dead. 

Katy: Ha 

Uh. 

Laura: I just can picture myself at a grocery store going up totally

innocently asking that question and then realizing it just like I do on here and halfway through my sentence just start dying laughing. 

Katy: Could

you 

Laura: Or I'll be with my toddler 

asking a question like that. 

Katy: has this poor guy, probably like some like, college kids, like, do you tenderize your meat often? Like,

Laura: And then they just start, the whole thing's just embarrassing.

Katy: There are so many situations where either myself or I see somebody else get into a

super 

embarrassing, awkward situation, I'm like, oh, I miss Laura. 

Like, 

just cause 

Laura: Yeah, yeah. 

Katy: Man, I'm not going to have to be thinking about that too, because yeah, I do like my, the stakes I have to not quite,

yeah, I don't know. Cause I don't like

them. 

I [00:03:00] don't

know. I 

don't

like I'm 

done. 

Laura: I still like it squishy and bleeding. But definitely, so medium rare for sure. Or medium at the most. I mean, I'll eat any steak, let's be real. But. 

Katy: But.

Laura: If I had it the way I wanted it.

Katy: Yeah. Huh. Yeah. Yeah. I mean, I guess I'm trying to think, I guess my only nature news

update is 

aliens, man. I mean, 

they're just, 

I 

Laura: As always, hey guess what? We're just gonna keep bringing it up. There's aliens.

Katy: aliens, It's a, it's a, you know, biology science discussion that I still don't know why again, why aren't, why aren't people freaking out more about it? 

I don't know. I don't

Laura: Cause there's way too much else to be freaking out about right now.

Katy: Alrighty. Well, do you want to go first? Do you want me to go first?

Laura: Let me go. Let me just go. 

 Okay. I have three freshwater things. one of them I know what yours is because wE came up, again, like we always do, of the million freshwater animals out there. We chose, of course, one that was the same. 

[00:04:00] So I just 

used a different one.

But, let me start with, I have two that are very similar. I'm gonna start small and get bigger. , because for me, a, a, For me, a true freshwater freak is a large one, 

right? 

Like, but, 

Katy: I do, I do want to give, I do want to give a shout out to Jeremy Wade, who was sort of the inspiration for this episode, though, in Monster Fish. Is that what it's called? Monster Fish? One of my, one of my favorite,

River Monsters, thank you. I was like, what is, I was 

like, I feel like it's 

not, River 

Monsters. 

Laura: to Jeremy Wade, I don't remember your show, but.

Katy: Yeah, yeah. Because, first of all, I love fishing. Which again is not a very good like opening tagline whenever you're like trying to date and meet guys like I could totally outfish you not a way to impress them because I know I can but he was definitely like the inspiration for this one because I love that 

show that's I don't think it's on 

anymore

but 

Laura: Well, it's just kind of cool to know what's out there besides just like the [00:05:00] deep water creatures, right? Like, which we've done before, we've talked about deep sea creatures, we know they're freaks. Let's talk about the ones that you might actually just run into, because they live right 

around. Yeah.

Okay, starting off with the one that you might not run into, at least around here, , is the vampire fish, a. k. a. the pierra. 

Which sounds like an under, like 

a deep ocean animal. Kind of looks like one, but not quite. Okay, so a little bit of background. It is a type of tetrafish. So if you've been to Petco and you're looking at the fish, a lot of people get tiny little tetras, which are just like a fishy looking fish.

Like they're not anything weird. But this is a kind, this is like a tetra

from a night, like on a nightmare. , so, the term petra, RA is kind of a catchall term for two fish in the same genus, but I wanted to focus on the larger of the two 'cause it's cooler. , and that one, the species is armada, , which means armored water wolf, 

which is also a cool Latin [00:06:00] name.

Katy: I was gonna say, yeah, that's a pretty As far as Latin names go, that's a pretty badass 

Latin name, cause a lot of them are pretty 

Laura: it's Hi Hydro, hydrous water wolf, and then Armadas Armor Armored. 

Katy: That's pretty 

cool. 

Laura: It's a 35 pound fish, which isn't that big of a fish, but like, let's be real, it's a pretty big fish, considering like what I fish out of a lake around here, you know, 

Katy: Yeah, true. Hmm. Yeah, 

Laura: they can get up to 4 feet.

The most, this is the most common of the two that are typically referred to as this, and they're a thin, silver fish. With two giant fangs growing up from the front of their bottom jaw that are two inches long. So, a two inch, two inch long teeth are pretty freaking 

Katy: just an underbite.

Laura: And it's, it's like an underbite. Yeah, yeah, yeah. Kind of picture a barracuda. It's very 

barracuda ish looking. Not as long. This is, again, this kind of looks like just a normal fish shape. Ball with big teeth. [00:07:00] And they're really thin. Like really thin and but 

rounded. So they come from the Amazon, Orinoco, and Essequibo river basins.

So, South America, the Amazon. , not to be confused with like a piranha. We're not talking like lots of teeth. We're talking two giant fangs and then some smaller teeth. They like to live in fast, deep water, like rapids or right below waterfalls. But they can also be found in lagoons and other, actually a pretty wide variety of freshwater habitats around those rivers.

 So why do they have these teeth and how do they hunt? Well, they're ambush predators, like a barracuda. But they wait at the bottom of a stream. So they're hanging at like the rapids, the fast water, everything's zooming by them. They are like parked at the 

Katy: Just waiting. 

Laura: Waiting, 

and they're perfectly camouflaged because 

they're this thin silver fish.

They just look like the aerated water around them. And then when they spot another fish, they [00:08:00] impale it with those two bottom teeth. There's like, impaled, 

Katy: You also know you've been, like, evolution wise, been, like, sittin chillin cookin for a long time. Whenever, like, you're adapted for, like,

aerated 

water. You know what I 

mean? 

Laura: right, that's so specifically niche. Like,

yeah. I Like,

it fast. They live fast. And, 

Katy: aerated.

water. I like me 

some fast aerated 

water. 

Laura: yeah, 

these are all about chasing waterfalls. 

Yeah, just one of these vampire fish chasing like just a waterfall. They sometimes migrate upstream to spawn, which is have their babies, and they are considered a sport fish.

Of course, anything with fangs like that, who wouldn't want to catch something that cool looking? , and they're pretty abundant. They're not in any danger of being overfished or anything like that. They're up there. Fairly common fish. So yeah, the vampire fish two giant teeth. Gotta google it

Katy: I mean, I [00:09:00] guess it's a good transition into mine because the first one I have also has weirdly space teeth cause it's big teeth, but, but like not a lot of them, which is weird, which I find really weird. Cause that's also say whenever you were talking about yours, I was gonna be like, I wonder what.

So mine is the Goliath Tigerfish.

So if you look that up, it very much so is like teeth, but they're like very much so spaced apart. So I wonder what 

adaptation wise, like what is that 

for? 

You know what I 

mean? 

Laura: Oh, oh

Katy: Isn't that creepy 

looking?

Laura: Yeah, and you're right they're crazily

spaced it actually looks like if somebody if you were like hey draw Draw a predator fish. And then I tried to draw a predator fish. That's what it would come 

Katy: Right. it's just 

like,

Laura: It's, it's very cartoonish looking. Like it's a cartoon 

fish 

Katy: It's, it's not 

Laura: It's eyes are 

Katy: Yeah. It's not like teeth side by side. It's like 

gaps. 

Laura: It's an [00:10:00] alligator. Like a straight 

Katy: But even alligators have like It's tooth, tooth, tooth, tooth, tooth. You know what I mean? Like, side by side, where like, this one is like, spaced

apart. Yeah, which is weird. Well, 

Laura: Ugh, I would never want 

Katy: right, this one, okay, so this one also has a lot in common with the one that you talked about.

Some weird similarities. , so this creature is, dominates its habitat, definitely, with its size, power, precision. So, let's explore a little bit more about the Goliath Tigerfish. So, the Goliath Tigerfish, Hydrocinus Goliath is a freshwater giant native to Congo Ri to the Congo River Basin and Lake Tanganyika in Central Africa.

These waters are the most powerful and dynamic on Earth, shaped by strong currents, deep gorges, and seasonal floods. This environment demands physical strength and adapt and adaptability, and the Goliath Tigerfish is perfectly built to meet those challenges, which I'll talk here 

in a 

minute. 

Laura: big [00:11:00] fish. 

Yeah. 

Katy: growing up to five feet long and weighing over a hundred pounds.

So literally my size, 

Laura: Yeah. 

Katy: uh, this, it's one of the largest predatory fish in

its habitat. It's muscular, which again, one of its largest, like 

what the 

F 

Laura: yeah. you're like, ugh.

Katy: yeah. First of all, I mean, the Congo is terrifying anyway. Like whenever 

you get into like the jungle 

Laura: Don't, isn't it, I'm sure crocodiles live in there. Yeah. Giant 

Katy: so it's muscular body is designed for navigating fast moving waters, making it a dominant force in an ecosystem full of competition.

As a seasonal breeder the Goliath tigerfish, , lays eggs in vegetative protected areas during the raiding season. And this timing ensures that the young have access to the resources they need to grow and survive. So they're pretty smart about it. So why is the Goliath tigerfish considered a predator?

Freaky fish. I, or whatever we're going to call this episode. Tiger fish isn't just another big fish is an apex predator that perfectly illustrates the [00:12:00] bizarre, just, I don't know, adaptations that you can find in a freshwater ecosystem. Like I was saying earlier, it's found and it's adapted to live in the Congo river basin and the Lake Tanganyika.

I think I'm saying that right. 90 percent of the time I say things wrong. I'm okay with it. , Which are two of the most challenging freshwater environments in the world. The Congo River flows with immense power featuring some of the strongest currents and the deepest channels of any river on earth.

While Lake Tanganyika's The unique thermal layers and vast depths create conditions unlike almost anywhere else. That lake is Africa's deepest lake, where it can reach well beyond or around a mile in depth of a lake.

Laura: that is really deep. Yeah, 

that's crazy. 

Katy: So thriving there definitely requires strength, agility, and hunter's precision, all traits that the Goliath Tigerfish have an abundance for.

[00:13:00] So again, like I said, they weigh up, or they can be up to 5 feet long and weighing over 100 pounds. And we were talking about the teeth a little bit whenever we started. Each tooth is up to an inch long, razor sharp, and they interlock 

perfectly like the teeth of almost like 

a bone. 

Bear trap if you 

think of it. 

Laura: gotta be why that they're spaced like that. They have to be spaced apart so that they can 

Katy: I, I, but, but if you look at it, okay, so if you look at a picture though, it's not like it's gonna be 

like, 

it, 

Laura: I mean, they must 

Katy: I guess, 

Laura: probably make a cage so that nothing can come 

Katy: I don't know, cause even, 

even, 

Laura: their teeth are thick, like, like the teeth.

on the fish I was talking about 

are 

Katy: yeah, these are 

Laura: These are like like shark 

teeth. 

Katy: but, but it's still like enough space that I think, okay, let's just say if you were a fish, like, in the 

inside, I feel like you could still like, 

see out,

Laura: Yeah. 

Katy: you know what I mean? 

Yeah, right, 

Laura: They have a glimmer of This 

fish is actually just a psycho. They want

their prey to have just a little [00:14:00] bit of hope. 

Cause it tastes better. 

Katy: The, the hope in its spirit tastes better, like, 

Laura: I want it to be 

Katy: right? Oh, goodness. But those teeth, they're pretty big, about an inch or so, long. And, and again, which I said, like, they are, you know, spaced a little bit apart. But, they're specialized that they protrude even when the fish's mouth is 

closed. 

, yeah, 

giving it an unmistakably fearsome 

appearance.

It is 

creepy looking. 

Laura: Fearsome? I 

guess creepy. But I almost 

like it's goofy 

creepy. Because of it's 

Katy: but if you were a little fish, but 

if 

Laura: Yeah. yeah. But if you were a little 

Katy: it would 

be terrifying. Or like I'm the same freaking size of it. Like that would be 

kind of 

Laura: Yeah. Oh, for sure. I don't want to get bit by that fish. It would hurt like crap. 

I'm 

Katy: But again, like I'm the idiot who is like, dude, I would totally love to catch a fish like that. Like I vicariously [00:15:00] lived through Jeremy Wade's show to be like, Oh, that would be amazing. Meanwhile, I'd probably poop my pants and then some like as soon as I got it, you know, hooked it on anyway.

So the Goliath tigerfish hunting strategy is, It's very similar to Laura. It's not just about brute force. This predator is opportunistic, known to hunt fish, nearly

its own size birds and even bats 

reports, 

reports of it leaping out of the water to snatch prey mid air. Sounds like a fisherman's tail, but it's very real.

Okay. Five foot fish

over a hundred pounds jumping that that

alone

is 

Laura: We'll just end snatching, I 

Katy: and a bat! 

Laura: people, here in America, people, you're thinking bat, you're like, 

oh, that's not so big. No, a big fruit bat from Africa. Yeah! 

Katy: which is

insane anyway. Cause

Laura: Yeah, so 

Katy: it's, it's, 

cool, but 

Laura: I would 

Katy: they're not slow. Like, bats aren't slow. You know 

what I 

Laura: [00:16:00] to see. No, no, no, no. But I 

imagine they're coming down to get water or 

to drink. Or 

maybe it's one of those fisherbats or whatever. Yeah, yeah, yeah. And just 

wham! Like, it would be so epic to 

Katy: Mm hmm. 

No, it definitely 

would be.

Laura: But like when you see like sharks eating the birds, right? Like you're like, aw!

Katy: But on this side, like, as cool as I think this fish is, I'm still on

the 

bat side. Like, I

feel so bad. Cause I 

love

bats. 

Laura: Yeah, 

it would be sad. But it'd be, I would,

I would be like, this is one of the coolest 

Katy: Yeah, the coolest, saddest things I've ever seen. Aw, aw, aw, the bat. Poor bat. So yeah, so it definitely can explode out of water, catch bats out of mid air.

 But yeah, so I think in itself, like the teeth being able to jump out and catch everything, that, I don't know. Again, you can't get any freakier than what it looks like. Cause again, it's 

Like Like I mean, again, depends on how you define what we're talking about, is like the freshwater freaks and [00:17:00] everything, but But yeah, so the Goliath Tigerfish, for, for me is number one.

It's, it's teeth, yeah, just everything about it, but the fact that it can jump out of water, it's super armored. Your first one and my first one definitely have, 

have a lot in common. Just, completely 

different continents, 

but yes, 

that's, 

Laura: yeah, totally different. But again, the

CoVirgin 

evolution, I mean, like you are made for what 

you eat. It always ends up being that way. So this is, 

Katy: Next freak! 

Go! 

Laura: next freak. Totally. Okay, so I'm increasing in size. That's, that's how I'm 

Katy: Oh, I'm so happy for 

Laura: next up, I, next up is the Chinese Giant 

Katy: Ooh, oh, I

didn't even think to 

do this one

this is a good one. 

Oh, 

this is a 

Laura: Because this lives in fresh water and I was like, it's bizarro. 

Katy: Whoa, wait. First, first, first, first, first, first. If anybody, if you guys are listening and you haven't seen this and you haven't, please Google it. It is, it'll blow your 

mind of, of, yeah, that 

it exists. So 

please, please, 

please 

Laura: It's straight out of an

[00:18:00] anime of like, a 

spirit from the wild came to talk to 

somebody. Yeah. 

Like, if, if I believed in, like, Earth

deities, this is one of them. Because it's huge and it's ancient looking. Like, there's just something about it. So, the Chinese giant salamander, the Japanese giant salamander, and I know, and the hellbender that are here in America are all in the same family.

They actually think that, I just was reading on an article, they think there are probably actually more species because of the genetics they've been seeing. 

They're, so maybe this is, because they live in remote places, they, anyway. 

Katy: Hmm. 

Laura: So it is the world's largest amphibian, so already pretty freaking cool. , I chose the Chinese one because it is the 

Katy: Yeah. It's the biggest. 

Laura: slightly smaller. World's largest amphibian, and

also known as a living fossil, which, if you haven't, go back and listen to our Living Fossils episode, where we talk about what that means, but basically, , an animal that has not changed through, since literally the dinosaurs, or before. Maybe not [00:19:00] the exact same species, but can be traced without breaking since then, and hasn't changed that much appearance wise.

Okay, so what do they look like? Let me paint you a picture here. It is a giant salamander, obviously, in the name. But, what do I mean by giant? Because, most salamanders that most people are thinking about are like four inches long. This one is commonly 3. 7 feet. But they can get to be nearly six feet long.

That's bigger than us! 

 Like just us, me, laying in the

water. Just a giant mud puppy. 

Katy: Which is so crazy. 

Gosh. 

Laura: And, , a hundred and ten pounds. So they're a little chunky guys. They have no gills. So, that's a little different because a lot of salamanders that live most, live primarily in the water retain gills. Like an axolotl.

But these guys, no gills. They are modeled, they are a modeled color of green, gray, and brown to look [00:20:00] basically just like the bottom of a stream. They're extremely 

Katy: was gonna say, I wouldn't be surprised. Like, Hellbenders, 

cause I'm, Yeah, I was gonna say, I'm from that area. I've never seen one. I would not be even

shocked if I've, like, come across it and just haven't noticed it. Because 

they, their camouflage is unreal. 

Laura: camouflaged. And they don't have none of their characteristics. Not only are they camouflaged, but they don't have any crazy All of their features are small. So what I mean by that is, like, they have four legs, but they're really stubby. 

Katy: They 

They, are 

stubby.

Laura: tiny beady eyes. So no crazy large features that might catch your eye, other than their just big thick body. They have a thick tail, a very blunt head, and they have a fold of skin all along the entire side of their body, so they look like Their skin is too big for their 

body. But it increases the surf Because these salamanders

breathe through their skin like they get oxygen from the [00:21:00] water, typically that's done with gills.

But these guys don't have gills. Instead, they increase the surface area of their skin by having that long fold and extra baggy skin, essentially, to be able to breathe better. And then, of course, they just have those, big They always are smiling. So, they just look 

Just happy in the water, living in fast flowing mountain streams and rivers. Just living their best lives, minding their own business, , entirely aquatic. These in particular, these salamanders, the Chinese ones, they live in the Pearl, Yellow, and Yangtze river basins. 

Katy: I was gonna say, I remember it being 

very specific. 

Laura: in the mountain streams, 

right? Because Since they're breathing through their skin, they need very aerated mountain, cold and clean 

streams. Obviously not like the, you have, the riffles in a mountain stream are what gives it the air, and then of course being like the first stop for water, it's the cleanest water. They're not gonna live in a really polluted river, [00:22:00] they'll die. 

Pristine streams.

What do they eat?

Some people are like, I don't know what a salamander eats. Basically, anything that they can fit in their mouths. Amphibians are not picky animals, really. I mean, it has to be alive, but otherwise, if it can fit in their mouth, they're gonna go for it. These guys create a vacuum in the water. If you've watched an axolotl, it's the same kind of thing.

They just like, puh! And like, just suck it 

in. And, 

they, 

Katy: again,

human adaptation, we kind of suck just like, right? That 

Laura: to death. Because Allura's definitely tried that and almost choked to death.

Katy: the one time my ex husband and I thought that we almost, like, Luke almost died, was because he inhaled a nacho, because he was like so excited about

chips 

and cheese, he was like, like chips and queso, he just inhaled it, and we're like, 

he

Laura: Yeah, well Allura, I've told to suck or slurp.

That's a slippery slope. That's 

a, that's 

Katy: Speak the truth, [00:23:00] 

Laura: terrible. I don't want, I

Katy: truth! 

Laura: They, are hunters, they're predators, so yes, they fit anything in their mouth, but like I said it has to be alive, they're not like eating vegetation and stuff if they can help it.

, they detect their prey using vibrations because they have nodes down their whole body to sense vibrations in the water, because they're teeny tiny eyes! They can't, I mean, they're not really using their vision, they're mostly just using vibration and then just, poof! 

Just like, 

Katy: Imagine, again, imagine if that was something even comes

close. We're 

just like, Huh? Food.

Like, we 

Laura: Just suck it in. Ask questions,

ask questions later.

Katy: I

Laura: They're mostly nocturnal, which I actually didn't know. 

 So they're coming out at night. And, 

they're light, the males, [00:24:00] Which I think is actually also really cute. The males create a den where they protect their eggs. The girls will come in, lay their eggs, and the boys are like, this is my spot. And I'm trying to imagine, like, how does a salamander protect its den?

I would love to 

Katy: Yeah, 

really. 

Laura: I mean, our salamander at work, when you feed her, she's 

like an alligator. She's slamming that worm around. 

But, they're not the fiercest of creatures. They don't have any sharp appendages. Nothing. Like, how do They just gulp at it, like, I don't know.

How do they protect it? I don't know. , and then, but, 

once the dad's done, once the eggs have hatched, the dad is donezo. No, there's no, no parental care. Most, like most large animals, it takes them a long time to grow and be mature.

They don't reach sexual maturity until they're five or six years old, which seems outrageous for something like an amphibian. 

And they can live 60 years in 

Katy: my goodness, I had no clue it was

that 

Laura: No idea. Right? Well, although, my mind was blown, because our salamander at work is a red salamander. Just normal salamanders can live to be like 14.

[00:25:00] That's crazy long compared to a frog and a 

Katy: Yeah, really, I didn't think 

it was that long.

Laura: It's gotta be something about like their low key lifestyle, right? Like frogs and toads are all like, Gah! Gah! Gah! You know, like, but, salamanders just chillin in the water. Gulping down food, barely reacting to things.

Sixty 

years! That's 

Katy: I had no idea. I mean, that's 

why they're that big. 

Laura: That's an old ti and again, like, it looks like an 

old person. It's all wrinkly and tiny, so it just looks like this wise

river 

creature. Like, that you would go ask for a favor. Or wisdom. You know what I mean? Like, like something, like a quest giver 

of some sort. That thing knows things, alright? And, also, never have I heard such a thing before. They actually can make a sound that sounds like a baby Dude, so this one I did know only because I think Nat Geo might have talked about 

Katy: this. 

Laura: That's [00:26:00] freaky. 

Katy: so one of the Nat Geo, like, documentary guys, I totally had a huge crush on. I forget his name though. But he did an episode with these

guys and did the sound. That was the first time I realized that they even make a sound because I 

had, I had no 

Laura: could make noises. Yeah. So Yeah.

baby crying. And then last but not least is the saddest news, which is that they are critically 

endangered. As with most, I mean a lot of, all

salamanders are, 

basically in 

Katy: Or amphibians, 

yeah. 

Laura: like so sensitive to pollution. But that's actually like not even, well, it's definitely a huge problem, right?

Habitat loss, all the normal things. But what is extra pressure on these guys? Because I think they said it started in the 70s. I want to say in the 70s. Started, they are massively poached for exotic meats. Like eating a giant salamander is a huge thing. Because they're so rare. It's like a thousand dollars a salamander or something, you know what I mean?

So people are just like So now, not only pollution, they need these very specific [00:27:00] habitats. Like, they're, uh, they're screwed, unfortunately. Thankfully, we can take care of them in captivity. But surely they won't be around 

much longer in the wild. Yeah. 

I know. I just wanna go chill with one. I would literally lay in a creek with a salamander.

Just hang.

I don't really like swimming. I just like hanging out in the water. So that sounds 

Katy: I was gonna say, I was gonna say, I don't know, the, the creeks, you know, or cricks I should say, back home, like, they're pretty, you know, pretty docile, like hellbenders and stuff. It's pretty chill. West Virginia, West Pennsylvania, where I'm from, it's just

like, 

I, yeah, just go hang out. 

That was a 

good one. 

Yep, that was a crick. 

That was a good one. Alright, my 

next one the giant freshwater stingray.

Laura: This is the one 

that I 

Katy: figured, I figured. 

Laura: It's just so 

Katy: it is, it is definitely a unique one. So the Giant Freshwater Stingray, Eurogymenis 

polypis, 

no, 

Laura: Guys, just notice that I never 

Katy: I know you 

never try, 

Laura: Katy's like, I [00:28:00] will try and I will

mess it up. 

Katy: time, doesn't 

Laura: It's her thing. 

Katy: but not only is it one of the largest freshwater fish in the world, but also one of the most mysterious because we

don't know a whole lot 

about this 

at all. 

Laura: Which is insane considering how huge it is. 

Katy: Because again, I feel like this is like eels where we don't know where eels really come from. Like,

what WTF? 

Laura: I don't understand such a thing. 

Katy: How 

is it 

2020, 

Laura: We know a lot of things now, but

Katy: It's 2024. We

understand so much crap about

stuff, but 

not, 

Laura: We've discovered aliens, but 

we don't 

It's the 

eels. 

Katy: fuck? Yes, that's right. 

Laura: that's 

what it is.

Or the eels are like their eyes. They're the eyes and the ears of the 

Katy: Could you imagine if this whole time, 

it's 

just been eels? 

Like, 

Laura: I met one 

once then. I did find a freshwater eel at one time. Freaking out. The kids that are in camp were not I mean, they were excited, but [00:29:00] I am losing it. I was like, guys, it's a freshwater eel! Like, nobody I'm freaking out. You don't even know! This thing is amazing! And look, so, if they are aliens, 

then 

Katy: the only time I've ever seen a freshwater eel was when I was in Australia.

That was, 

that was it. But never 

a 

giant, 

Laura: Croydon Creek, baby. Our creek is

cleaning up for freshwater eels, which is 

Katy: No, that is, that is actually pretty cool. But never have I come across a freshwater stingray, giant freshwater 

stingray. It's because they're found in Southeast Asia's major river systems, including the Mekong 

and Chalparai. Again, no clue if I'm pronouncing that right. I looked these 

Laura: Sorry, everybody. 

Katy: zero out of 10 for pronunciation.

 This species has long been a source of awe for communities living near these waters known locally as the queen of the river, which I found was 

interesting. 

Yeah. 

Laura: I like that. Yeah. [00:30:00] Then you look at a stingray and you're like, 

Katy: Kerween. Yeah, she is 

a queen. 

Laura: Queen! 

Katy: So it holds the place of regional folklore for sure, where its massive size and venomous tail have inspired tales of river monsters.

And again, Jeremy Wade did do an episode on this one. I think. Physically the stingray is perfectly adapted to its environment. Its wide, flat body allows it to bury itself in the riverbed, using the silt and sand as natural camouflage. , it has, it's a very like muted, brown, grayish coloration. 

Yeah, it's, yeah, it's ugly coloration.

, but it helps it to blend into its surroundings, making it nearly invisible in the sediment rich waters that it calls 

home.

So, 

Laura: So 

they must live in slow moving, right? For there to be So,

much sediment 

on the 

bottom. They must be slow moving rivers because of 

Katy: No, no, exactly. Yeah. Yeah, definitely different than like the Congo, the last one I talked about, which is just like, or your first one, which is like the vampire one, which is aerated water. No, [00:31:00] this is like everything's chill and slow moving here. , so while modern science has uncovered somewhat details about the species, much about the giant freshwater stingray remains elusive.

So fossil evidence tells us that the stingrays and their relatives have existed for over 150 million years, predating the age of the dinosaurs. Which is 

Laura: Yeah. Oceans first. Yeah. 

Katy: So this ancient lineage gives a species an almost otherworldly quality as if it's a living relic in Earth today. Which again, living fossils.

Go check out that episode. Don't remember when we did it, but it was a while 

ago.

Laura: Yeah, and It was a good 

one. 

Katy: good one. Uh, this blend of natural adaptation and deep history has cemented a place in both science and myth, especially for the local guys. So, or the local culture. So, why is it our theme? Well, the giant freshwater stingray

is definitely more than just, I don't 

know, 

another, 

Laura: Your average stingray. Yeah, [00:32:00] yeah.

It's 

freaking 

Katy: it's, giant.

Um, so the body spans up to 16 feet and, and, 

Laura: That is 

Katy: and weighing more than 1, 300 pounds.

Which 

is just 

Laura: I can't imagine existing in the water with something like that

large without it being like,

a whale. 

Katy: like, 

this is 

Laura: But it lives in a river. 

Katy: yeah, this is a freshwater 

system.

Laura: This isn't an ocean. It's Excessive for no reason. Like, 

Katy: Excessive for No, 

Laura: animals usually live in the ocean. Like. 

I mean, I'm sure the rivers in China are very large, but, 

like, not even the Amazon has 

Katy: No, not like, no, not this big. No, not So. Again, what's astounding is about how flat or pancake like that the body allows it to remain almost invisible, blending seamlessly with the sediment at the bottom of the rivers.

Unlike more familiar stingrays that people think of, which often a habitat that O open oceans, this species has adapted its unique challenges of [00:33:00] fresh water ecosystems and, and has kind of used it to their advantage. So, let's talk about, like, some of those unique adaptations. So, again, Stingray, you think about, the venomous

barb, 

you know most people think of the barb, R.

I. P. Steve 

Laura: R. I. P. Steve. 

I know where we would go. 

Katy: I know every millennial's soul just crushed a little bit, but so they have a venomous barb located on its tail and this spine can reach lengths of up to 10 inches or just over 10 inches and it is equipped with serrated edges enhancing its ability to inflict definitely significant wounds.

The barb is not merely like Just a physical weapon though. It also delivers that venom that can cause intense pain, swelling, and tissue damage. This is the part I did not know about stingrays that I thought was incredibly cool. So this, the venomous composition, because immediately I'm like, okay, snakes, venom, hemotoxin, neurotoxin, like 

Laura: Or, like, [00:34:00] a bee sting. yeah, 

Katy: So the composition is and it varies among stingray species. In freshwater stingrays, studies have identified high levels of enzymes, such as hyalodridase, which increases the size of toxins of tissues, leading to greater tissue necrosis and inflammation. This enzyme actively contributes to the severe symptoms observed and Interestingly enough though, research indicates that venom composition can vary with the age and sex of the stingray.

I had no idea about 

this. 

Yes, so juvenile stingrays produce a peptide mix of pain inducing agents, while adults have venoms rich in inflammatory proteins that cause tissue necrosis. So this variation suggests an adaptive mechanism to different ecological pressures throughout their different life 

stages.

Laura: [00:35:00] Right, like, the juveniles are like, get away from 

me. It hurts. 

Katy: where the adult 

Laura: the adults are maybe using it to 

Katy: you're gonna slowly die a painful death.

Laura: Yeah. But like maybe they use it like in hunting, like in feeding. Whereas the juveniles are probably just, you're too close, go away. 

Katy: Yeah, 

yeah,

Laura: Like do they 

use their tail at all to hunt? 

Katy: it doesn't really, not that I found. Again, we don't really know a whole lot about these animals at all. 

Laura: Maybe they just, maybe they only use, like maybe if it's really big, Like,

a big fish they're trying to eat, they like, shank it a few times. Just 

Katy: Just shank it Just shank it. a few 

times. 

Laura: shank it a few times. 

Katy: It's, 

Laura: Cover it in a blanket and shank it. 

Katy: just, imagine like a prision stingray.

That's immediately where I go. 

Laura: It's horrible. 

Katy: Oh, [00:36:00] goodness. But I didn't, but I didn't know that, that it varies depending on age and

sex. I 

I, had no 

Laura: really weird. And I don't know any other animal that can do that. I mean, like, there's more venomous and less venomous with age, but not actually 

Katy: Yeah, not different. Because again, I was like, oh, is this more of a hemotoxin, you know, neurotoxin? Like, what does it do? No, it's it's totally different depending on the age and the, the sex of it. 

Laura: Fascinating. 

Katy: is highly flexible allowing the stingray to

deliver rapid whip like strikes with 

incredible 

precision. 

Laura: A. K. A. 

shanking. What? 

Katy: Again prison prison stingrays 

Laura: Quick. Quick. A few 

Katy: You're right. But this agility enables it to defend effectively against potential predators or threats. It's important to note that while envenomation from the giant freshwater stingray is rarely fatal to humans, it can definitely lead to severe pain and complications if not properly treated.

So [00:37:00] 

oftentimes when people get like hit by the stingrays and stuff, I mean, RPC,

Roman, , which was a man, was he a stingray or 

manta

ray? 

Laura: It was a stingray, but from the ocean, but I don't 

remember what type. That one was just 

Katy: Yeah, that was just like horrible placement everything about it 

was 

just bad. 

Laura: Like, that just went into his chest. Normally that's not like 

It's not like they're trying to go 

Katy: Yeah Dad was just, yeah, just unfortunate, but. So this one is, even though, most of the time, like, the envenomation of it isn't going to kill you, it's secondary, so it's like infection or something else, like the necrosis that causes 

infection, 

Laura: moving, giant 

river. Yeah. 

Katy: so there's, there's a lot of other things. So, , Despite its size and striking features, the giant freshwater stingray is one of the least, like I said, studied fish in the world. But Dr. Zeb Hogan, a biologist with the Megafishes Project, which I gotta deep dive into that more, has been one of the few scientists to lead the significant research efforts of this species.

And he truly is, like, [00:38:00] one of the few people that actually

have. So using

Laura: So interesting. I'm, I'm always fascinated by, if you're an ichthyologist, why aren't you looking at These things 

These things are like the coolest 

Katy: Yeah, yeah, the neat things. Yeah, but I mean you got to think too. I mean, I guess get getting to it finding them You know what? I mean? Like there's some definitely financial complications in the 

Laura: And access. Yeah. 

Katy: But he was using tagging and tracking methods Hogan and his team have discovered some of the stingrays migratory patterns and habitat preferences But still even then much remains unknown some of the unknowns we don't know is there are still unsure by 

its life expectancy like not really have any idea

Laura: Well, cause you can't keep this thing in a freaking tank. It's massive! I mean, I wonder, I 

mean, I guess juveniles, 

Katy: but it's it's it's too big to and and again everything lives longer in captivity So it's like well, how long does this live? You know, in her world, the stingrays breeding habits are also poorly understood, though its live [00:39:00] bearing reproductive strategy, a trait shared with its marine relatives, you know ocean stingray, the same way.

It sought to give its offspring a higher chance of survival in the unpredictable environment. So yeah, so that's the, the giant freshwater stingray, which is just like, we know something about it, but not a whole lot, but still super 

mysterious.

Laura: That's awesome. For my last one, sorry Diggles, he's trying to sleep on me. I'm sorry. The last one now I'm going back to Big Toothy Fish. This is my large, my largest one. , so I was like, alright, if I can't do the Fresh Giant Stingray, what else am I gonna do that's really awesome and huge?

 Cause like for me I'm just thinking like a river monster 

essentially. , We've been to South America, we've been to China, and now we're coming right back here to the good old U. S. of A. For the Alligator Gar. , which, Katy and 

Katy: Listen, We need to share this 

Laura: Arkansas. We knew they existed. 

Yeah.

Katy: We had a docent [00:40:00] at the zoo we worked at which swore up and down she used to hunt alligator gar with a broomstick. With a hook on it. A broomstick and a 

hook. Mind you, when she told us this story, she's like 90, 100 years old. , telling us that yeah, she used to just go out with her family and just, 

Laura: I didn't even remember that, but I'm not surprised. 

Katy: no, and she was Miss Kentucky.

Yeah, this lady was like Forrest Gump 

of the South, in female version. 

Laura: Awesome. She's really great. 

So it is one of the lar one of the largest fish in the United States, which is crazy. That means sturgeon are bigger, but I wanted to go with the gar, , cause they're 

cool. They're also a living fossil, so this is the third living fossil so far that we've talked about.

 They have been around a hundred

million years. These are fish that found their niche and just did 

Katy: Right? They're like, this is good, we survived, 

we're gonna keep 

Laura: If it's not broke, don't fix it 

Yeah. So what do they look like? I mean, you can kind of picture it. I mean, he's something called an alligator, Gar. You're like, okay, big [00:41:00] teeth. So, size wise, I'm always impressed by giant fish.

I'm just like, so typically not more than 79 inches, which is still huge. Like, typical fish. Typically 79. But the record is 10 feet. 10 feet! 

Katy: I can't

for an 

alligator, 

Laura: And it's not like the stingray, which is just all surface area and no substance. Like, this is a thick fish. It is round. Typically, they're 100 pounds.

But the record is 350 

pounds. That's 

like a sail that's like an ocean 

fish, right? So the largest one ever was caught in the St. Lawrence River of Arkansas in 

Katy: Not even shocking. Not 

even 

shocking. 

Laura: No, yeah. They've got good

clean water, 

Katy: Well, yeah, it's clean. It's rivers, but there's like swamps like not even 

shocking that the 

biggest one was found 

in 

Laura: Yeah, and like, not a huge population, so they're probably not being, like, they weren't being overfished in the [00:42:00] 30s at the time. So yeah, huge. Probably lived there forever. , they look basically just like a torpedo. So these are ray finned fishes. They are in the group of ray finned fishes, which look very different.

From some of our other fish that we've talked about. So, these are rafined fishes, which look very different than a lot of, your typical fish. The tetrafish I was telling them looks like a fish that everybody imagines in their head. A rafined fish, these are like those living fossil fish like the sturgeon, the gars, they look like a long torpedo and they have really cool scales, they're called ganoid scales, which are diamond shaped scales and hard as, bone, they're not like a flimsy little fish scale, these are armored tanks of fish, they're brown or olive colored so they're really camouflaged, they have, and they have a short broad, flat snout.

So it looks like you took a fish and then you shut its face in the door. Because it's literally completely flat, like a platypus. Like it looks kinda like a [00:43:00] platypus in a shapefish, or a fish shape. And in that snout are two rows of needle like teeth, and on the top, and one row on the bottom, which I actually don't think I knew that it had the two on top.

Katy: Yeah. 

Laura: and not only does it have two on top, because, I mean, think shark, okay? No, no, no, no, no, no. Rather than them being, like, two rows close together, the inside row is, in, more in the middle of its mouth, and those ones are the largest, and then the outside teeth are short, so it, like, traps the fish in its mouth, and then prevents with the second row, 

Katy: Again, this is another one where it's like those poor little fish are just looking out like, help me.

Laura: Yeah, this one lives, so the alligator gar, like I said, lives here in the United States, but specifically in the Mississippi River Basin and like the coastal plain of the Gulf of Mexico, so like Texas coastal plain right there, Louisiana, but most of the time in fresh water. However, they are pretty tolerant of brackish and salt water, of all these [00:44:00] fish, they're pretty tolerant, which has helped them live a hundred million years.

They, the water that they do live in is slow moving, like the stingray that Katy was talking about. These guys live in rivers, lakes, bayous, bays, and like I said, mostly fresh water but sometimes salt. Feeding. Now of course if it has teeth, shove that are sharp, it's gonna be a meat eater. And it is also an ambush predator like my first fish.

But unlike my first fish, it doesn't hang out on the bottom. It actually hangs out at the top. They've been known to just sit at the top of the water and pretend essentially to be a log and wait for things to come by and then just eat them. And again, eating anything that will fit in its mouth. Typically it's fish, but it can also be birds, small mammals, reptiles, literally anything that comes by that fish or like lands on it thinking it's a log.

Harp. 

Katy: Imagine, imagine though, like, clearly, okay, it, as far as we know, this fish does not have a conscious thought pattern. [00:45:00] But, also imagine to be like, like, how did it, evolution wise, like, how did it figure out 

like, I am a 

log.

I should act like a 

Laura: Yes. I 

Katy: know what I mean? Like how 

did, cause everything else 

is, 

Laura: I guess just more 

survived that hung out and 

Katy: yeah.

Like, 

do they know that they look like logs? Probably 

not, but they are. And you know what I mean? So they don't know why. They don't know why 

it works. Yeah. 

They don't, they don't know why it works, But it does.

Laura: But it's work for them. And then their life cycle is kind of interesting. I did not know that their eggs are poisonous to human beings. 

Katy: I had 

Laura: That's so random. 

Katy: Huh. 

Laura: Yeah. Can't eat, can't eat gar 

eggs. You can eat them, but not their babies. And that's not true of a lot of fish eggs you can eat.

Sushi, but not them. And their babies have an adhesive disc on, I think it's their top, I can't remember if it's top or bottom, but essentially they have a tiny little suction cup that they can latch onto [00:46:00] vegetation. So when they're babies, they hang out in the reeds and the weeds. And then when they get big enough that they're gonna be okay, they lose that disc and go out into the open water.

Katy: humans have adapted so 

suckily.

Laura: we're so lame, yeah. And then, like I said, like all these large animals, we're talking long life and long time to get this big. So they don't reach sexual maturity until, females, not until they're 11 years 

Katy: Oh my 

goodness! 

That's so 

Laura: That's a long time to 

be non 

Katy: For a fish? 

Laura: Yeah. 

Katy: That's crazy! I had no

clue. 

Laura: And then females, Because they take the longest, they also get to live the longest, thankfully.

 They live to 50 and then males lived about half that. A 50-year-old fish is pretty old 

fish. And yeah, to get like a 10 foot 

giant girl, , 'cause that's who it'd probably be. It's the 

Katy: Yeah, really. 

Laura: But as like, you know, as scary as 

these look and the press that they get, like Katy and I were told you do [00:47:00] not go.

Tubing on a river in Arkansas because you'll get bit by a 

gar. There are no documented cases of

attack of a gar on a 

Katy: For the record, Laura and I totally

still, 

Laura: I would definitely have done it, and I definitely got out of 

Katy: yeah, right? Yeah, we went kayaking down one of the, again, Arkansas has some, I mean, it's a natural state for a reason. It has some gorgeous rivers and stuff to

go 

down. And yeah, we didn't hesitate to do it, whenever 

we, we 

unfortunately 

lived

Laura: I actually

have been way more 

scared of the , what do they call them? muskies that are in, Raystown Lake in 

Katy: Dude, I've caught a muskie before 

Laura: with some big fish. 

Katy: I've caught a muskie before. I have a picture somewhere of it, maybe when I was like 12 or something, I caught a muskie. Dude, those things, I mean, that, that is, as a kid when you catch those, those are pretty damn

scary to 

catch.

Laura: Yeah, so I mean, I Agar is a respectable looking fish, 

but it's snout is [00:48:00] pretty short 

Katy: looking 

fish.

Laura: Like, I mean, like, 

Katy: It is. No, it 

Laura: that's a giant fish with sharp teeth. But we're not talking, , this is not a fish like a barracuda that is like, da da da da da da. Like, this is a log with teeth.

Pretty avoidable, one 

would think, you know what I mean? Like, ambush as in, you have to bump into this 

fish for there to be a 

problem. , I can, I can take that. And, if I bump into a fish and get bit, that one's on me. So it's not like I'm, like, actively afraid of 

Katy: Yeah, that's 

fair. 

Laura: and like I said, no documented cases.

No,

none. None. I'm sure there's plenty of stories, but no documented cases. , unfortunately, these are an endangered species because, endangered in some states and threatened in other states, , because of overfishing and just habitat. , you can't get, if you're not gonna even have babies until you're 11, that's a huge blow to 

Katy: It, no it is. That's, that's a 

Laura: you live in ha 

Katy: That's a

very

long

time. 

Laura: You can't have any other pressures, right? 

We've talked about [00:49:00] other animals that have, like, when they take that long, you can't have habitat loss, and you can't have overfishing, and you can't have pollution that, , already you have been selected to have a hard time with an old population.

, and then, , but, they are considered a sport fish and a food fish. So people do eat them. People will do fish with them for sport. And you 

can, in the states that they are not considered an endangered

or threatened species. 

The 

Katy: Cause alligator gar balls, not balls, but the meat formed into 

Laura: Yeah. 

Katy: are a very like popular like dish, which is bizarre, but it's almost like they like, like not a patty, but they would just make a ball out of them and you can get them 

in restaurants 

and

Laura: Like the, like a hush 

Katy: Yeah. Yeah. Essentially. Yeah. Yeah.

Laura: Yeah. 

Katy: Alrighty. Well, my last freak is my, one of my favorites. And again, just cause, again, River Monsters, Jeremy Wade, this is one that you'll

[00:50:00] constantly hear him 

talking about, is the Arapaima. 

Laura: Yes! Dude, I don't 

even know much of, the

only thing I know about this fish. Throwback, everybody, all of our analysts are not gonna know what I'm talking about. But guys, back in the day, when com you could get Computer games on a cereal box, okay? When they were pushing those computer games because they were new.

One of them was the Amazon Trail. It's the best game that has ever been created for the computer, perhaps. Because it's essentially Oregon Trail, 

Katy: In the 

Amazon, 

Laura: better. And you get to fish, and that's the 

fish that you wanted to catch because it was the most bang for your buck. So we're on Spearfishing 

Spearfishing 

Katy: I don't know why Jeremy Wade likes it so much. But it definitely, the arapaima is one that he talks about. So the arapaima, which is arapaima gigas, one scientific name 

I can 

Laura: Gigas. 

Katy: the only, besides like gorilla, gorilla, you know, the only scientific name I can say, 

Laura: [00:51:00] Arapaima gigas. 

Katy: one of the most iconic freshwater fish in the world. Found in slow moving rivers, floodplains, and lakes, this fish has adapted to the unique challenges of its environment, thriving in the warm, often murky waters of the Amazon. So scientifically, like I said, classified as the Arapaima gigas, this species is part of the Arapaimaidae family,

a 

group of fish that has existed for millions of 

years. 

The 

Arapaima, 

Laura: actually very 

similar body type. Like their body type looks 

very similar to the Gar. As far as the 

Katy: Yeah, yeah, yeah, Yeah.

not the snout part, but the 

rest of it 

Laura: Yeah. And even the fact that it is a 

little flattened. It's just not 

Katy: it's, Yeah.

it's, not as extreme, but it definitely has 

some of it. , so like I said, the air Pima is native to the Amazon river basin where inhabits a waterways rich in sediment and organic materials. , these rivers and floodplains are dynamic [00:52:00] ecosystems with water levels fluctuating dramatically.

Between wet and dry seasons. And the Arapaima has clearly had no problem surviving in, in either or. 

Laura: Yeah. 

Katy: because again, I don't know if you guys have ever seen like dry seasons in the Amazon. It's not as drastic as that in Africa, but it's still, it's still pretty extreme. When it comes to the size, the air PAMA is almost unmatched in freshwater ecosystems.

Again, it goes up to, I mean, we know the stingray is already bigger, but as far as a, 

like a quote unquote traditional fish, yeah. It can go up to 10 feet long and way, way well over 400 pounds, with 

its, 

Laura: that's even, yeah, that's massive. 

Katy: incredibly, 

incredibly strong. Yeah. Its scales 

are

e. 

Laura: They have these at the Baltimore Aquarium. 

Katy: yeah, I think they had them at the Pittsburgh aquarium too, because I think it was Pittsburgh.

It was one of either that or the Baltimore care aquarium that I went to. And I was like, Oh, and it 

was, 

Laura: Yeah. They're in like [00:53:00] the Amazon 

Katy: it was a pretty cool, pretty cool job. I don't know, a

Bucket fish

list. I don't know if that's like a 

thing, but like

one of those

species, you're like 

Laura: Bucket fish 

list. 

Katy: but you know what I mean? Like one of those species, you're like sweet.

I'm never going to see it in the wild, but like, this is awesome. 

Laura: Yeah. 

Katy: So their scales are equally impressive. They have thick overlapping plates with basically like a metallic like sheen that shifts between green and red hues. So this coloration provides excellent camouflage, helping the air pyma blend in the shadowy depths of the habitat that lives in the Amazon.

Laura: Christmas fish. 

Katy: I didn't even think 

about that. And I'm definitely like color association person too. So the arapaima, , I mean, other than its sheer size, is a textbook example of why freshwater ecosystems are home to some of the most bizarre and unbelievable creatures. Everything about this fish, including its physical traits to, you know, its role in the ecosystem, makes it, I would, to [00:54:00] me anyway, the, like, freak of freshwater.

Like, it, 

Laura: The Freak O Fish. 

Katy: what?

Laura: The Freak O 

Katy: Yeah, the freak of the fish.

 Like my goliath tigerfish, this one also can leap out of the water with explosive force.

And these leaps are so powerful that they've been known to knock over predators or

even 

unsuspecting fishermen. So again, fun to say. 

Yeah, you 

imagine, 

Laura: 400 pounds, 

Katy: right? But you imagine like those tails, like you come back and people are like, Oh, they're fisherman tails. No, there's some legitimacy behind it. , cause again, if you get hit by a 400 pound, 10 foot long 

fish, 

Laura: Yeah.

it's like very eel 

Katy: But yeah, who's gonna believe you?

No one. Crazy? Yes. But no one will believe you. So, they're also an apex predator. The air pimer rules its ecosystem. Its diet includes fish, crustaceans, and even the occasional bird. Again, it leaps out of the water. Showcasing its versatility and

dominance. So, I talked [00:55:00] a little 

Laura: Which is so interesting because, , not, like, when you look at this fish, I mean, you could think predator, but it's not toothy every other fish we've talked about has been, like, very apparently toothy. This one does not show its teeth. You 

don't, 

Katy: No. No, no, But, So, here's the one of the cool things about it. That we didn't really dive deep into any of the other fish we talked about. At least for the ones that I picked, or the other one that I picked. It, it wasn't, so the Arapaima, and it's like the armored scales that they have, the other tiger, Goliath tigerfish that I picked, yeah, it's , solid, , fish scales, but it's a little bit more than what a typical fish scale is.

Arapaima, however, are a natural masterpiece, combining both strength and flexibility to literally provide unparalleled protection. So the outer layer of their, Fish scales are highly mineralized outer surface that is exceptionally hard, featuring ridges and [00:56:00] protrusions that act like natural armor.

Scientists have measured the micro hardness at approximately 550 MPa's, which I'll get here to in a second, which is a measure of the pressure of force a material can withstand, MPa. So, what is an MPa? It stands for megapascal, which is a unit of pressure or stress. One MPa. Equals 1 million pascals or 1 million newtons of force per square meter.

For comparison, a human bone is about like 150 MPa's. 

Laura: like, it can take a hundred, before it breaks. 

Katy: Structural steel. Structural steel. Steel guys. is around 250 MPAs for mild steel and about 500 MPAs for high strength steel. The hardness, like I just said, of the aima is 550 

MPA. 

Laura: Stop [00:57:00] it. What? 

Katy: So it is 

Laura: Just diamond scales? 

Katy: Than a, than steal. Like 

that's how hard, 

Laura: you fillet 

it? How do you fillet 

Katy: I mean, I'm sure you can still cut through it, you know what I mean? Because it's not like 

it's

a, because 

You 

Laura: You can't cut steel with just a normal knife. It must have to go between 

Katy: I was gonna say that's how you would have to do it would be 

go between it because you can't 

like I 

Laura: you just, like, you try and stab this fish and your 

knife just breaks. Like, you're like

God, just 

Katy: Yeah, I mean essentially that it has full on armor

Laura: that's amazing. 

Katy: ichthyologists out there 

listening

that can 

like, 

please help us understand this more.

Because yeah. And again, it's like, okay, is this just taking like a scale in a

lab and like, analyzing it or like, what's the function, you know what I 

mean? Like, is 

it 

like a, 

Laura: Has anyone tried to stab an arapaima? Let's see. Not that I

want 

them to. But if it's happened

already, 

Katy: there have been several, there have been several documentaries on this fish species, and several, several times, , [00:58:00] people have gotten physically very hurt trying to catch one because they , whenever they lash, 

Laura: Yeah, the thrashing, 

Katy: it like, destroys them.

, So, yeah, so, it, it's definitely because of the scales. It's definitely rivals some of the most advanced, advanced engineering materials that we found. So, now, the inner layer, which is, like, beneath that armor layer. Lies a collagen rich foundation arranged in a bollard or a twisted plywood type pattern.

This structural design enhances flexibility, allowing the scales to absorb and

dissipate 

mechanical forces. Which is even crazier, so not only 

is it

like 

Laura: What are they defending themselves 

from? Dinosaurs? 

Katy: Us stabbing them? Like, Like, 

Laura: Yeah, like,

how, why did they 

Katy: I don't know. 

I,

to, to, to rule 

Laura: we know, are they a living fossil? 

How, how long have they been around? 

This particular fish, do we know how long they've been around? Because maybe they truly did evolve to 

defend 

themselves from dinosaurs. 

Katy: um, [00:59:00] probably been around

23 million years. 

Laura: okay, well there you 

Katy: So I guess, I mean, it probably adapted like way back when, whenever swimming dinosaurs and stuff could eat it. And then it just kind of kept it. Cause it's like, well, everything is kind of sucks evolved now. But I mean, I don't, 

you know what I mean? Like, yeah. So yeah, so the air pyramid scales don't just stop bites, it prevents cracks or fractures from spreading, ensuring that the fish stays protected even under any sort of high impact, force.

So, the other thing that makes an air pyramid pretty crazy is its air breathing evolution. Because they can breathe air, and it's one of its most extraordinary adaptations. So unlike most 

fish, 

Laura: I've heard about, there's a couple of other fish that live in the Amazon, because of those muddy, 

un oxygenated 

Katy: Yeah, they have to. What else are they gonna do? So the air pyma is an obliquate, like Laura just [01:00:00] said, air breather, which means it surfaced regularly to gulp air to survive. This behavior is powered by its modified swim bladder, which functions as a primitive 

lung. So like Laura said, 

Laura: Well, and you can see its little mouth is literally made for like, like it's like,

Katy: yep, because it has to, 

because it has 

to. So

because, 

Laura: I didn't know it was an obligate. I didn't 

know, like, they just don't have gills? 

Katy: well, it's, they, they do, but when it, because all the waters are so

murky,, because oxygen 

levels

are so, 

They have to supplement with 

something because it's so stagnant or like sediment rich like and that's where a lot of it lives 

It's not like it's polluted or anything. It's just it's so 

sediment. 

Yeah, it's so sediment filled that there's not enough oxygen there So while most fish will struggle with those conditions, the arapaima thrives dominating as the predator, where oxygen is often scarce, so even if a fish kind of like wanders into this area, arapaima is like, boom, he's, he's going to be [01:01:00] gone. , so unfortunately, the arapaima's oppressive traits have also made it a target for overfishing. Its size and, and apparently tasty boneless fillets are often highly sought after, leading to a decline in the population in some area, including, well, Not including, but also another factor is habitat destruction because it's in the Amazon, , and deforestation.

So the Arapaima is a really cool big fish, but it, which has evolved, you know, 23 million or however long I say. 

Laura: 23 

Katy: 23 million. , and then more of the idiots that like, are taking it out. Just because we're like, meh, you don't get to live in your land. But, it has some really, really cool features that, to me anyway, Yes, it's one of my favorites, but I also think it's like the apex, like,

freak 

fish of fresh water for sure.

Laura: Dude, if for

science, somebody fished that fish and it was dead, certainly, I would try to see what kind of impact, or, [01:02:00] 

that, , are we talking because even armadillos can, reflect a bullet depending on the 

size. , what could this fish if you shot a steel beam,

it would do nothing.

 If you

Katy: I don't know, 

man. 

Laura: crazy. That is just the craziest thing I've ever heard. That's like a straight up dragon

Katy: it is essentially. It essentially is. Yeah.

Laura: That's 

Katy: Arapaima. One of my

favorites. All right guys. Well that is our episode on freshwater freaks. Make sure you 

go check us 

Laura: And, so not to totally scare you, you know, next time you want to go wade around in a 

river, but. 

Katy: I mean, as long as you're not in the 

Laura: cool stuff out there. 

Katy: Yeah. I think you'll be 

Laura: But you can't even 

go here in La No, not in the Mississippi River 

Valley. Woo! 

Katy: more of our videos on YouTube. We're going to distinguish a little bit more between YouTube and Patreon and kind of add some more things there for people who, help support us because Laura and I, you know, our whole, you know, [01:03:00] 1.

77 for these ads, , Woohoo! You know, supporting us really helps us to be able to continue this and everything. So yeah, go ahead and check us out on Patreon. I'm gonna work on uploading some more fun stuff, but we also do these episodes, edited episodes on YouTube. The unedited stuff is all on, Patreon.

So go support us so you can continue to help us. And thanks again, guys, because this is Season 

11, 

which is 

Laura: Yeah! 

Katy: crazy. crazy. 

crazy,

Laura: Yeah, and we got lots of good stuff. We're gonna be doing it just like last season.

Where we did episode, mini sode, episode, mini sode, episode, mini sode. So you will hear us again next week. It will start our mini sode series. 

Katy: Let's just tell them. Let's just tell them, because I think it's gonna be, I think it's gonna be really cool. So last, last season we focused on the caves, and in the season break we did 

Laura: No, it was bogs. Bog, Yeah. 

caves, 

Katy: Yeah, this one we're taking it out of this world, but um, and we're, and we're doing [01:04:00] cosmic critters, which is different things we've, different weird things we've launched into space, essentially.

, Yeah, so that'll be, we'll hit on one episode next week, and those, like Laura said, we'll alternate, and so that's how we're gonna go, we, we, we like that style, it seemed to be pretty popular, got a lot of downloads last season, kind of alternating 

those. 

Laura: Plus it's sustainable for Katy and I, 

Katy: Sweet lord, yeah, 

we're busy moms man working full time jobs.

I wish this was our full time job, but it's not so we're busy. So these these full episodes with mini episodes seem to work really well and everybody seems to really like it , so yeah, so you're gonna hear full episodes and then we're gonna go to these mini episodes and we have some Again, we say this every season, but I am so excited for some of the episodes.

We have this season to talk about we're gonna hit on some pretty cool and unique things that we haven't hit on yet And so i'm i'm really excited for this season So if you guys can go to patreon and support us, it would it would mean a ton it doesn't take much I mean most people [01:05:00] won't even notice it out of their bank account and but it really really really 

helps laura and I so if You guys 

Laura: Yeah, to be able to actually, cause it does cost money to 

Katy: It does.

Yeah, it definitely, it definitely does. So until then go check us out on YouTube. Listen to more episodes, help us get those downloads. We can get those like

10th of a penny cents worth of 

ads. 

Laura: sweet sweet ad 

money. 

Katy: 1. 77 Lauren. I got to split it down. So, all right guys, thank you very much. And then, , we will talk to you next week for our first cosmic critter episode.

Laura: See ya.