Nessariostoma granulosum is a lightly armored pseudopetalichthyid placoderm from the Hunsrückschiefer Lagerstätte of Early Devonian Germany. The type and only known specimen is an articulated, but very incomplete individual, deformed and elongated, consisting of a large, incomplete, tubercle-covered head, a long, beak-like rostrum, and some of the trunk, with a total length of 18 centimeters.[1] N. granulosum was once placed in Stensioellida, though most other experts regard it at as a pseudopetalichthyid: Denison 1978 regards it as a placoderm incertae sedis because the specimen is deformed and so poorly preserved so as to stymie proper attempts at classification.[1]

Nessariostoma
Temporal range: Emsian
Artist's reconstruction
Scientific classification
Kingdom:
Phylum:
Class:
Order:
Denison 1975
Family:
Paraplesiobatidae

Berg 1940
Genus:
Nessariostoma
Species:
N. granulosum
Binomial name
Nessariostoma granulosum
Broili, 1933

References edit

  1. ^ a b Denison, Robert (1978). Placodermi Volume 2 of Handbook of Paleoichthyology'. Stuttgart New York: Gustav Fischer Verlag. pp. 119–120. ISBN 978-0-89574-027-4.

External links edit