Mesodermochelys is an extinct genus of sea turtle known from the Campanian to the Maastrichtian (Late Cretaceous) of what today is Japan and from the Maastrichtian of Chile. One species is known, the type species M. undulatus; it was given its binomial name by Ren Hirayama and Tsutomu Chitoku in 1996. Studies of its skull indicate that it was a primitive member of the Dermochelyidae (leatherback turtle family) that was closely related to the Protostegidae. It has been described as the best representative of Mesozoic dermochelyids.
Mesodermochelys is an extinct genus of sea turtle known from the Campanian to the Maastrichtian (Late Cretaceous) of what today is Japan and from the Maastrichtian of Chile. One species is known, the type species M. undulatus; it was given its binomial name by Ren Hirayama and Tsutomu Chitoku in 1996. Studies of its skull indicate that it was a primitive member of the Dermochelyidae (leatherback turtle family) that was closely related to the Protostegidae. It has been described as the best representative of Mesozoic dermochelyids.
==Description== thumb|left|Restoration of two Mesodermochelys (middle) and other sea creatures swimming around a Kamuysaurus carcass Like other dermochelyids, Mesodermochelys had elongated front flippers. One fossil found in Japan's Kagawa Prefecture had a carapace estimated to be in length, and specimen from Hokkaido had carapace up to . Largest specimen is estimated to have shell around , possibly comparable with Archelon. Only the neural or spinal scutes, or individual plates, of the carapace are well grooved.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).