Heintzichthys

Heintzichthys Temporal range: Late Devonian: Famennian, 371.1–359.3 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	†Placodermi
Order:	†Arthrodira
Suborder:	†Brachythoraci
Family:	†Selenosteidae
Genus:	†Heintzichthys Whitley 1933
Species
Heintzichthys gouldii (Newberry, 1885) (type)
Synonyms
Dinichthys corrugatus (Newberry, 1893) Dinichthys gracilis (Claypole, 1897) Stenognathus corrugatus (Newberry, 1889)

Heintzichthys is an extinct monospecific genus of arthrodire placoderm that lived what is now Europe and North America during the Famennian stage of the Late Devonian period. The type specimen was discovered in the Cleveland Shale near Cleveland, Ohio, in the United States.[1]

Phylogeny

Heintzichthys is a member of the family Selenosteidae of the clade Aspinothoracidi, which belongs to the clade Pachyosteomorphi, one of the two major clades within Eubrachythoraci. The cladogram below shows the phylogeny of Heintzichthys:[2]

Eubrachythoraci

Coccosteomorphi  Pachyosteomorphi  Rhachiosteus pterygiatus Dunkleosteoidea  Eastmanosteus calliaspis Eastmanosteus pustulosus Kiangyousteus yohii Golshanichthys asiatica Westralichthys uwagedensis Dunkleosteus raveri Dunkleosteus terrelli Dunkleosteus amblyodoratus  Heterostiidae  Heterosteus ingens Yinosteus major Aspinothoracidi Tapinosteus heintzi Bullerichthys fascidens Kendrickichthys cavernosus Bruntonichthys multidens Dinichthys herzeri Hadrosteus rapax Gorgonichthys clarki  Selenosteidae  Heintzichthys gouldii Pachyosteus bulla Gymnotrachelus hydei Stenosteus angustopectus Brachyosteus dietrichi Melanosteus occitanus Rhinosteus parvulus

According to a 2022 Jobbins et al. study, Heintzichthys was found to be a sister taxa to Gorgonichthys.[3]

	Gymnotrachelus
	Gorgonichthys Heintzichthys

References

1. Hansen, Michael C. (2005). "Phylum Chordata—Vertebrate Fossils". In Feldmann, Rodney M.; Hackathorn, Merrianne (eds.). Fossils of Ohio. ODNR Bulletin 70. Columbus, Ohio: Ohio Department of Natural Resources. p. 290.
2. Zhu, You-An; Zhu, Min; Wang, Jun-Qing (1 April 2016). "Redescription of Yinostius major (Arthrodira: Heterostiidae) from the Lower Devonian of China, and the interrelationships of Brachythoraci". Zoological Journal of the Linnean Society. 176 (4): 806–834. doi:10.1111/zoj.12356. ISSN 0024-4082.
3. Jobbins, Melina; Rücklin, Martin; Ferrón, Humberto G.; Klug, Christian (2022). "A new selenosteid placoderm from the Late Devonian of the eastern Anti-Atlas (Morocco) with preserved body outline and its ecomorphology". Frontiers in Ecology and Evolution. 10. doi:10.3389/fevo.2022.969158. hdl:10550/85583. ISSN 2296-701X.