#placodontia

Psephochelys

Psephochelys — вимерлий рід плакодонтів з пізнього тріасу Китаю. Представлений єдиним видом — Psephochelys polyosteoderma, названим у 2002 році на основі єдиного часткового скелета, знайденого у відслоненні формації Фалун карнійського віку в провінції Гуйчжоу.

Повний текст на сайті "Вимерлий світ":

A study of Saurian morphology: Sauropterygia (part 1)

Sauropterygia (lizard flippers), is a group of marine reptiles known for their specialized pectoral girdle, adapted to support powerful flipper strokes.

The first group of shown here is Placodontia (tablet teeth).

Placodus was a heavily built early placodont which anatomically wasn’t well adapted to live in water. This suggests that placodonts were likely to be terrestrial animals which moved back to the sea to feed.

Cyamodus and Henodus were two later placodonts which evolved bony plates superficially resembling that of turtles. However, Cyamodus’ body was composed of two separate carapaces, while Henodus’ shell had far more bony plates which formed intricate mosaic pattern on its back.

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