Английская Википедия:Astraspis

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Шаблон:Short description Шаблон:Automatic Taxobox

Astraspis ('star shield') is an extinct genus of primitive jawless fish from the Ordovician of Central North America including the Harding Sandstone of Colorado and Bighorn Mountains of Wyoming. It is also known from Bolivia.[1] It is related to other Ordovician fishes, such as the South American Sacabambaspis, and the Australian Arandaspis.

Description

Файл:Astraspis desiderata.jpg
Astraspis desiderata

Nearly complete fossils suggest the living animals were about Шаблон:Convert in length. The body had a mobile tail covered with small protective plate-like scales of less than Шаблон:Convert and a forebody covered with plate-like scales larger than Шаблон:Convert. The specimen from North America (described by Sansom et al., 1997) is to have had relatively large, laterally-positioned eyes and a series of eight gill openings on each side. The specimen was generally oval in cross-section. The protective bony plates covering the animal were composed of aspidin (chemically similar to modern shark's teeth), covered by tubercles composed of dentine.[2] It is from these tubercles (which are generally star-shaped) that the name 'Astraspis' (literally "star-shield") is derived.

References

Шаблон:Reflist

Other sources

Michael J. Benton, Vertebrate Palaeontology, 3rd edition, 2005

External links

Шаблон:Pteraspidomorphi Шаблон:Taxonbar

Шаблон:Pteraspidomorphi-stub Шаблон:Ordovician-animal-stub

  1. Sacabambaspis janvieri. PY Gagnier - Vertébré ordovicien de Bolivie, 1993
  2. Sansom IJ, Smith MP, Smith MM and Turner P (1997) "Astraspis: The anatomy and histology of an Ordovician fish" Palaeontology, 40 (3): 625–642.