sarcopterygian

6

It’s that time of year again! Here’s some more Pride Prehistoric Life (cause dinosaurs are awesome but we never see their awesome origins)
In order we have:
Gay Trilobite - “y'all can’t prove they weren’t rainbow-coloured”
Non-binary Sarcopterygian - “totally inexplicable in modern binary terms”
Polyamorous Icthyosaurus - “the only one I finelined because… reasons”
Grey-Ace Ammonite - “ayyy (get it? Alliteration with the letter ‘a’? I’ll just leave…)
Genderfluid Stethacanthus (aka ironing-board shark) - "um… angles?”
So the Stethacanthus and the Icthyosaurus aren’t the best in terms of anatomy and proportions but they’re still my babs and I love them
I used the terms I identify with (I’m grey-aro too but I left it out because I’m lazy) so it was very fun!

4

How can you not be enchanted by this goofball? I don’t know how anyone could consider these fish boring.

For anyone who’s wondering, Linnaeus is a West African Lungfish (Protopterus annectens). These fish are ancient sarcopterygians whose closest relatives, besides the few other lungfish species, are coelacanths and tetrapods. Lungfish, being true to their name, possess a lung that is highly similar to the lung of a tetrapod which they use to draw oxygen from the air. In fact this species is an obligate air breather meaning they must draw oxygen from the air as their gills have lost the ability to extract oxygen from the water column in any significant amount. West African Lungfish can grow to 2 ½ - 3 feet long in aquaria and are an aggressive fish best kept alone.

7

So I recently had the opportunity to purchase a West African Lungfish (Protopterus annectens). These are ancient sarcopterygians that grow very large and are pretty unique animals. They possess many traits that early tetrapods had and many odd characteristics for fish such as a four chambered heart and primitive lung structures. These are traits more commonly found in amphibians (some of the first tetrapods) rather than most fish.

After talking it over with my SO, whom obviously has a say in whether or not we could house this fish as an adult, we came to the conclusion that we can make the space for him if he ends up growing 3ft+. With lungfish living 20 years, and quite often more in captivity, they are definitely a long term commitment. In fact there is a Queensland lungfish at the Shedd Aquarium in Chicago that has been in their collection since 1933. (That’s 81 years!) Visually lungfish look so reminiscent of a salamander or axolotl, it’s hard to believe they’re a fish at all. There are only six extant species of lungfish with the largest species reaching over 6ft in length.

Almost all lungfish species are wild caught so I want to give this little guy a nice environment that allows him to behave as he would naturally. Right now I have him set up in a 20gal with some sand and plants while he adjusts. He is already roughly 6-7in in length so he’ll need to go into a 29 gal or 40b as soon as he settles in and I’m certain he’s healthy. He was a rather unexpected purchase and so I have to hunt down a stand for the bigger tank since I used to keep them on a large dresser which I no longer own.

Behaviorally hes a pretty sedentary critter except for when food is around or when he goes up for air. The rest of the time is spent napping among the plants, under the driftwood, or sifting through sand for food he may have missed. I also didn’t have a net large enough to for him but I was pleasantly surprised to find he doesn’t mind being handled gently. Right now he’s being fed NLS large fish formula 3mm sinking pellets and frozen bloodworms. Once I’ve had him for a while I’ll likely write a caresheet on P. annectens. I’m open to name suggestions as well!

3

Linnaeus just keeps getting fatter and not gaining much in length. He is such a funny fish, it’s hard to get pictures of him behaving naturally (napping, digging, etc) because if I’m in the room he’s just constantly begging for food.

For anyone who’s wondering, Linnaeus is a West African Lungfish (Protopterus annectens). These fish are ancient sarcopterygians whose closest relatives, besides the few other lungfish species, are coelacanths and tetrapods. Lungfish, being true to their name, possess a lung that is highly similar to the lung of a tetrapod which they use to draw oxygen from the air. In fact this species is an obligate air breather meaning they must draw oxygen from the air as their gills have lost the ability to extract oxygen from the water column in any significant amount. West African Lungfish can grow to 2 ½ - 3 feet long in aquaria and are an aggressive fish best kept alone.

ok so im a big ass nerd and i’m thinking about what dragons might be like in Real Life

i super love archosaurian dragons, but i was thinking about the fun “four legs one pair of wings” hexapod kinda dragon.

it would be a sarcopterygian, a sister group of tetrapods. i figured that the pectoral fins, which developed into the forelimbs of tetrapods, could develop into the wings in dragons instead. the pelvic fins would develop into forelimbs, and maybe the second dorsal fin and the anal fin would shift to a horizontal alignment instead of vertical. here’s a cool coelacanth diagram

External image

so this fishie used its wingy fins to jump and glide above the surface to idk eat flying bugs and evade underwater predators i guess. its other fins were used maybe to help steer and also to land and drag itself back into the water if it jumped too far.

eventually it spent so much time gliding out of the water and dragging itself around with its fins that its descendants started wandering around on land too and thus grew leggies. and wingies.

later forms would have the four legs one pair of wings arrangement and of course become adapted for powered flight. dragons arose from this, and something resembling gryphons could be part of this group too.

later on in their evolutionary lifespan flightless forms could appear, some maybe retaining the extra pair of limbs for some other function, and some just kinda losing them altogether, and some maybe even losing all their legs and turning into notsnakes. some would also return to the water and be cool sea serpents! 

it sounds plausible to me but i need to research more about sarcopterygians and early tetrapod evolution and figure out how to actually draw reasonable intermediate stages of evolution in this group so that i can draw reasonable dragons and things based off this because now im really excited about it. wow im gay bye