What is "brachydeiroidea"

Brachydeiroidea is a superfamily of small to moderately large-sized arthrodire placoderms from the Late Devonian of Europe and Eastern North America.

Brachydeiroids have, in cross section, a highly compressed body, a pointed, sometimes highly elongated snout, and tremendous orbits. The plates of the trunk shield are noticeably shortened: in Synauchenia, the trunk shield and head shield are fused together as a single, immovable unit. The superficial anatomy of brachydeiroids is extremely diverse.