Megapterygius (meaning "large wing") is an extinct genus of mosasaurine mosasaur from the Late Cretaceous Toyajo Formation (Hasegawa Muddy Sandstone Member) of Japan. The genus contains a single species, M. wakayamaensis, known from an almost complete skeleton.
Megapterygius (meaning "large wing") is an extinct genus of mosasaurine mosasaur from the Late Cretaceous Toyajo Formation (Hasegawa Muddy Sandstone Member) of Japan. The genus contains a single species, M. wakayamaensis, known from an almost complete skeleton.
== Discovery and naming == The Megapterygius holotype specimen, WMNH-Ge-1140240002, was discovered in 2006 by Akihiro Misaki in sediments of the Hasegawa Muddy Sandstone Member of the Toyajo Formation near the peak of Mt. Toyajo in Wakayama Prefecture of Japan. The specimen consists of a partial skull, a complete cervical and dorsal vertebral series with more than 40 vertebrae, ribs, both front flippers, and the left hind flipper.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).