Cyathaspididae is an extinct family in the

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 exis ...

order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...

Cyathaspidiformes Cyathaspidiformes is an extinct order of heterostracan vertebrates known from extensive fossil remains primarily from Silurian to Early Devonian strata of Europe, and North America, and from Early Devonian marine strata of Siberia. Anatomy Like ...

.The Classification and Evolution of the Heterostraci. L. Beverly Tarlo, Acta Palaeontologica Polonica, 1962 Cyathaspididae contains most of the genera originally contained within Cyathaspididae, as well as those genera contained within Irregularaspididae, and Poraspididae. In addition to the type genus, †''

Cyathaspis ''Cyathaspis'' is the type genus of the heterostracan order Cyathaspidiformes. Fossils are found in late Silurian strata in the Cunningham Creek Formation, New Brunswick, Canada and Europe, especially in the Downton Castle Sandstone of Great B ...

'', Cyathaspididae contains the following genera: †'' Americaspis'', †'' Archegonaspis'', †''

Capitaspis ''Capitaspis'' is an extinct genus of cyathaspidine cyathaspidid heterostracan jawless vertebrate known from the Late Silurian Somerset Island Formation ( Pridolian epoch) of the Northwest Territories, Canada. It contains a single species ...

'', †'' Dikenaspis'', †'' Dinaspidella'', †'' Homaspidella'', †'' Irregulareaspis'', †'' Nahanniaspis'', †'' Pionaspis'', †''

Poraspis ''Poraspis'' is an extinct genus of heterostracan. Fossils are found in Late Silurian and Early Devonian marine strata of Norway, Canada and the United States The United States of America (U.S.A. or USA), commonly known as the United ...

'', †'' Ptomaspis'', †'' Seretaspis'', †'' Steinaspis'', †'' Torpedaspis'' and †'' Veronaspis''.

References

External links

* Cyathaspidida Prehistoric jawless fish families {{Pteraspidomorphi-stub