title: Brachydeiroidea
text: # 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.
  
  ## Families
  
  ### Brachydeiridae
  
  A diverse family of variable forms, restricted to the middle to late Frasnian of Europe.
  
  ### Leptosteidae
  
  This family is represented by two species in the genus Leptosteus. Leptosteids differ from brachydeirids by having comparatively smaller orbits and more elongated trunk shields.
  
  