A new Lepisosteiformes (Actinopterygii: Ginglymodi) from the Early Cretaceous of Laos and Thailand, SE Asia

A new genus and new species of ginglymodian is described from the Aptian Gres superieurs Formation of the Savannakhet Basin, Laos (Lao People's Democratic Republic), found at the Ban Lamthouay locality. The fish is known from a single isolated head, which shows enough diagnostic characters to characterize a new taxon. It represents the first named actinopterygian fish from the Mesozoic of Laos. Among the derived characters are a very short and deep head, a series of very deep anterior infraorbitals, and a mosaic arrangement of the suborbitals. Recognition of this new form led us to identify isolated bones previously found in the Thai Khok Kruat Formation in Thailand, a lateral equivalent of the Gres superieurs Formation. Two localities, Ban Saphan Hin and Khok Pha Suam, have yielded remains, in particular bones of the skull roof and of the circumorbital series as well as a partial postcranial body, assignable, with caution, to the new genus. When included in a cladistic analysis, the new taxon is placed a...