Pteraspidoidei is an extinct suborder of

heterostracan Heterostraci (Ancient Greek, ἕτερος+ὄστρακον "those itha different shell" i is pl. of -us is an extinct subclass of pteraspidomorph jawless vertebrate that lived primarily in marine and estuary environments. Heterostraci exi ...

vertebrate Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...

s. It contains the more derived taxa within

Pteraspidiformes Pteraspidiformes is an extinct order of heterostracan agnathan vertebrates known from extensive fossil remains primarily from Early Devonian strata of Europe and North America, and from Upper Silurian Canada. Anatomy A pteraspidiform heter ...

, such as ''

Pteraspis ''Pteraspis'' (from el, πτερόν 'wing' or 'fin' and el, ἀσπίς 'shield') is an extinct genus of pteraspidid heterostracan agnathan vertebrate that lived from the Lochkovian to Eifelian epochs of the Devonian period in what is now ...

'' and '' Errivaspis'', though, some protopteraspidids, such as '' Doryaspis'' and ''

Panamintaspis ''Panamintaspis snowi'' is an extinct species of pteraspidid heterostracan agnathan which existed during the early Middle Devonian period of Death Valley, California.Elliott, David K., and Robert R. Ilyes. "New Early Devonian pteraspidids (Agnat ...

'', share various features with these derived pteraspidids.

References

* Pernègre V., 2006. - Un nouveau pteraspidiforme (Vertebrata, Heterostraci) du Dévonien inférieur du Spitsberg: nouvelles données paléo-ontogéniques. Geodiversitas, fasc. 2, t. 28 Pteraspidiformes Fish suborders Devonian jawless fish Silurian jawless fish Prehistoric animal suborders Silurian first appearances Devonian extinctions {{Pteraspidomorphi-stub