Choristodera

From Tokaia

Choristoderes, also known as champsosaurs, are a linage of crocodile like aquatic reptiles (however, unlike crocodiles they lack scutes and their nostrils are located at the tip of the skull), which became extinct in our world. Their exact relationships within class Sauropsida aren't very well understood; they have been classified both as archosaurs and as lepidosaurs.

[edit] In Terra Alternativa

The evolution of choristoderes in Terra Alternativa parallels that of Earth's; however, those in this parallel Earth remained alive, occupying the niches of gharials (which either became extinct or evolved into terrestrial, ant-eater like forms). An extinct linage, Pelagochampsosauridae, gave rise to marine forms in the Eocene period, successfully outcompeting the last marine crocodiles; however, changes in the oceanic currents, plus the evolution of the first marine cynodonts, eventually caused their demise at the Oligocene period (although some remaining species managed to survive until the Pliocene).

Nowadays, most species either belong to the family Champsosauridae, or to the family Lazarusuchidae. The first occur naturally in the Americas, while the later in Asia and Australia. The first resemble pretty much the gharials crocodiles from our world, while the later are more similar to large aquatic lizards. Both occupy a similar niche, feeding mostly on fish and freshwater invertebrates.

[edit] In What if Dinosaurs

In What if Dinosaurs the evolutionary history of choristoderes was similar to the previous ones; like in Terra Alternativa, some marine champsosaurids have also evolved.

[edit] See also

Choristoderes on Wikipedia