Ctenaspis (Ctenaspis kaieri) is an extinct genus of heterostracan cyathaspid agnathans from the early Devonian of Canada, Norway and Russia 416.0 to 412.3 million years ago. Species of Ctenaspis are typically 10 to 18 cm long with the max length being 40 cm long. The genus contains only one known species, namely Ctenaspis kaieri.

Ctenaspis
Temporal range: Early Devonian 416.0-412.3 mya
C. dentata
Scientific classification
Kingdom:
Phylum:
Class:
Order:
Suborder:
Family:
Genus:
Ctenaspis
Binomial name
C. kiaeri
Zych, 1931

C. kaieri has no adorbital opening and only two dorsal and ventral plates . The dorsal plate is fused with branchials and the plates notably thin. C. kiaeri has its branchial openings located at the posterior edge of armour. The dorsal shield is flat.[1]

Sources

edit
  1. ^ "Palaeos Vertebrates 40.500  Pteraspidomorphi: Amphiaspidida". 2008-03-19. Archived from the original on 2008-03-19. Retrieved 2022-07-05.
  • Vertebrate Fossils and the Evolution of Scientific Concepts by W. Sargeant
  • BioLib.cz
edit