Early Carnian (235 MYA), Austria
Saurichthys calcaratus (spurred lizard fish)- a species of saurichthyiform known from the Carnian of Austria. An elongated barracuda or pike-like marine predator, they hunted by ambush, relying on short bursts of speed to quickly capture smaller aquatic animals in their long beak-like jaws (which can make up a third of their body length). A symmetrical tail fin and identical caudal and anal fins near the end of the long body provide quick, small strokes that can propel the animal forward with minimal effort to catch its prey by surprise. Members of the genus reached around one metre in length, with reduced scale covering as an adaptation towards greater speed. One of the later surviving species of Saurichthys, it was part of the subgroup Saurorhynchus, which were one the few saurichthyiforms to survive past the Triassic (although the species itself seemingly did not).
Thoracopterus niederristi (Niederrist’s chest/thorax wing)- a species of thoracopterid known from the Carnian of Austria and Italy. A type of gliding fish, with a powerful asymmetrical tail capable of propelling the animal out of the water, and broad pectoral fins to keep its body aloft for tens of metres. Although similar in many respects, thoracopterids were unrelated to modern exocoetids, but likely evolved flight through the same pressure of natural selection, as a defence mechanism to escape fast pelagic predators, of which there were certainly no shortage during the Triassic, particularly as marine reptiles were just beginning to appear. Most species of thoracopterids show severe reduction of squamation, possibly as a weight reduction adaptation, but Thoracopterus is a primitive genus that retains a fully scaled body.
This picture was uh, originally going to feature Tusoteuthis and Nyctosaurus, but in the middle of drawing the water, I double-checked and apparently they aren't definitively known from the same time or place (Nyctosaurus: Santonian United States (Niobrara Formation), Tustoteuthis: Campanian Canada (Pierre Shale)), so... that was a bust. In hindsight I'm still not sure this is actually true but I already finished this new picture by the time I triple-checked so maybe you'll see that one later some other time.
I didn't want the water to go to waste though so now the picture is fish.
also, great work of course