Protopteraspis

Protopteraspis Temporal range: Early Devonian^[1] PreЄ Є O S D C P T J K Pg N

Reconstruction of P. gosseleti
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Pteraspidomorphi
Subclass:	Heterostraci
Order:	Pteraspidiformes
Family:	Protopteraspididae
Genus:	Protopteraspis

Protopteraspis is an extinct genus of pteraspidid heterostracan agnathan with fossils known from Lower Devonian marine strata in Western Europe. The animal's somewhat flat build has led some to believe that it was a bottom dweller, living in freshwater areas. It has been described as "somewhat unspecialized".^[1] Its snout was round and narrow, shorter than that of its immediate relatives. Protopteraspis also did not possess the cornua (horns) found on the headshields of other pterapsids; rather, it had "small points" behind the gill opening.^[1] It did possess a "medium-sized" dorsal spine.^[1] Plates covering the headshield had ridges of dentine. It is theorized that the headshield formed in youth and that it grew via growth of the plates, which fused in adulthood. The scales of the animal were "small and diamond shaped".^[1]

References

1 2 3 4 5 Palmer, Douglas; et al. (2009). Prehistoric Life: The Definitive Visual History of Life on Earth (first American ed.). New York City: DK Publishing. p. 130. ISBN 9780756655730.

This article is issued from Wikipedia - version of the 6/18/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.