Cartorhynchus lenticarpus

Christine Dell'Amore “First Amphibious "Sea Monster" Found; Fills Evolutionary Gap”

カリフォルニア大学デイヴィスの藻谷亮介氏*1などが中国安徽省巣湖市*2馬家山で、ジュラ紀の水陸両棲の爬虫類Cartorhynchus lenticarpuを発掘。その体長は約20メートル。

Ryosuke Motani, Da-Yong Jiang, Guan-Bao Chen, Andrea Tintori, Olivier Rieppel, Cheng Ji & Jian-Dong Huang “A basal ichthyosauriform with a short snout from the Lower Triassic of China”


The incompleteness of the fossil record obscures the origin of many of the more derived clades of vertebrates. One such group is the Ichthyopterygia, a clade of obligatory marine reptiles that appeared in the Early Triassic epoch, without any known intermediates. Here we describe a basal ichthyosauriform from the upper Lower Triassic (about 248 million years ago) of China, whose primitive skeleton indicates possible amphibious habits. It is smaller than ichthyopterygians and had unusually large flippers that probably allowed limited terrestrial locomotion. It also retained characteristics of terrestrial diapsid reptiles, including a short snout and body trunk. Unlike more-derived ichthyosauriforms3, it was probably a suction feeder. The new species supports the sister-group relationships between ichthyosauriforms and Hupehsuchia, the two forming the Ichthyosauromorpha. Basal ichthyosauromorphs are known exclusively from south China, suggesting that the clade originated in the region, which formed a warm and humid tropical archipelago in the Early Triassic. The oldest unequivocal record of a sauropterygian is also from the same stratigraphic unit of the region.


See also