Heterosteus

Heterosteus; Temporal range: Middle Devonian, Givetian PreꞒ Ꞓ O S D C P T J K Pg N ↓
	Life reconstruction of Heterosteus ingens
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Placodermi
Order:	Arthrodira
Suborder:	Brachythoraci; not Gross, 1932
Family:	Heterosteidae
Genus:	Heterosteus; Asmuss, 1856
Species
	Heterosteus asmussi Agassiz, 1844 (type); Heterosteus ingens; Heterosteus rhenanus;
Synonyms
	Chelonichthys asmussi;

Heterosteus is an extinct genus of heterosteid placoderm known from remains discovered in Europe and Greenland.

Description

This genus includes the largest species in the family, and are among the largest arthrodires, as well, with the type species, H. asmussi, having an estimated body length of up to 6 metres (19 ft 8 in).^[1] The genus differs from Herasmius by having the orbits on slightly longer eyestalk-like projections. The various species are found in Givetian-aged deposits in Europe and Greenland. With the except of the German H. rhenanus, all species are known from freshwater deposits: H. rhenanus is based on fragments found in a marine deposit.

References

^ Denison, Robert (1978). Placodermi Volume 2 of Handbook of Paleoichthyology. Stuttgart New York: Gustav Fischer Verlag. p. 66. ISBN 978-0-89574-027-4.

[1] Denison, Robert (1978). Placodermi Volume 2 of Handbook of Paleoichthyology. Stuttgart New York: Gustav Fischer Verlag. p. 66. ISBN 978-0-89574-027-4.

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