Pteraspis

Pteraspis; Temporal range: Pragian PreꞒ Ꞓ O S D C P T J K Pg N ↓
	Restoration of P. rostrata
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Superclass:	Agnatha
Class:	†Pteraspidomorphi
Subclass:	†Heterostraci
Order:	†Pteraspidiformes
Family:	†Pteraspididae
Genus:	†Pteraspis; Kner, 1847
Type species
	Cephalaspis rostrata; Agassiz, 1835
Species
	Pteraspis rostrata (Agassiz, 1835); Pteraspis dixoni (White, 1938); Pteraspis mitchelli (Powrie, 1864);

Pteraspis (meaning "wing shield") is an extinct genus of pteraspidid heterostracan agnathan vertebrate that lived in the Pragian epoch of the Devonian period in what is now Britain and Belgium.

Description

Fossil of P. rostrata

Reconstruction of Pteraspis, Estonian Museum of Natural History

Like other heterostracan fishes, Pteraspis had a protective armored plating covering the front of its body. Though lacking fins other than its lobed tail, it is thought to have been a good swimmer thanks to stiff, wing-like protrusions derived from the armoured plates over its gills. This, along with the horn-like rostrum, made Pteraspis very streamlined in shape; a perfect quality for a good swimmer. Pteraspis also had some stiff spikes on its back, possibly an additional form of protection against predators. It is thought to have fed from shoals of plankton just under the ocean surface,[1] and is found in association with marine fossils.[2][3]

Pteraspis grew to a length of 20 centimeters (8 inches).

References

Parker, Steve. Dinosaurus: the complete guide to dinosaurs. Firefly Books Inc, 2003. Pg. 59

Palmer, D., ed. (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 23. ISBN 1-84028-152-9.
Lankester, E. R. (1870). "I.—On a New Cephalaspis Discovered in America, etc". Geological Magazine. 7 (75): 397–399. doi:10.1017/S0016756800209485.
White, E. I. (1938). "New Pteraspids from South Wales". Quarterly Journal of the Geological Society. 94 (1–4): 85–116. doi:10.1144/GSL.JGS.1938.094.01-04.05.

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[EoDP-1] Palmer, D., ed. (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 23. ISBN 1-84028-152-9.

[Lankester2009-2] Lankester, E. R. (1870). "I.—On a New Cephalaspis Discovered in America, etc". Geological Magazine. 7 (75): 397–399. doi:10.1017/S0016756800209485.

[White1938-3] White, E. I. (1938). "New Pteraspids from South Wales". Quarterly Journal of the Geological Society. 94 (1–4): 85–116. doi:10.1144/GSL.JGS.1938.094.01-04.05.