Acanthothoraci

Acanthothoraci Temporal range: Early to Middle Devonian
Weejasperaspis gavini, Murrindalaspis wallacei & Brindabellaspis stensioi
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	†Placodermi
Order:	†Acanthothoraci Stensiö, 1944
Families
Weejasperaspididae † Hagiangellidae[1] † Palaeacanthaspidae †
Synonyms
Acanthothoraciformes

Acanthothoraci (spine chests) is an extinct group of chimaera-like placoderms closely related to the rhenanid placoderms. Superficially, the acanthoracids resembled scaly chimaeras and (relatively) heavily armored ptyctodonts. They were distinguished from chimaeras by their large scales and plates, a pair of large spines that emanate from their chests (thus, the order's name), tooth-like beak plates, and the typical bone-enhanced placoderm eyeball. They were distinguished from other placoderms by differences in skull anatomy and by patterns on the skull plates and thoracic plates that are unique to this order.