Ectosteorhachis is an extinct genus of freshwater megalichthyid tetrapodomorphs that inhabited what is now North America during the Permian period (Cisuralian epoch, about 299 to 272 million years ago).[1][2] It is the only known member of the subfamily Ectosteorhachinae. Fossil remains are known from the United States.[3]

Ectosteorhachis
Temporal range: Asselian to Kungurian
Life restoration
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Sarcopterygii
Clade: Tetrapodomorpha
Clade: Megalichthyiformes
Family: Megalichthyidae
Subfamily: Ectosteorhachinae
Borgen & Nakrem, 2016
Genus: Ectosteorhachis
Cope, 1880
Species:
E. nitidus
Binomial name
Ectosteorhachis nitidus
Cope, 1880
Ectosteorhachis fossil at the AMNH

It contains a single species, E. nitidus from the Asselian/Sakmarian to Kungurian of Oklahoma and Utah (Hennesey and Cutler Formations). A second species, E. ciceronius Cope, 1883 from the Garber Formation of Oklahoma has no type specimen and is thus invalid. Remains tentatively assigned to Ectosteorhachis are known from the Washington Formation of Ohio.[3][4][5]

References

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  1. ^ Philippe Janvier; Gaël Clément; Richard Cloutier (2007). "A primitive megalichthyid fish (Sarcopterygii, Tetrapodomorpha) from the Upper Devonian of Turkey and its biogeographical implications" (PDF). Geodiversitas. 29 (2): 249–268. Archived from the original (PDF) on 2013-11-14.
  2. ^ Florian Witzmann; Rainer R. Schoch (2012). "A megalichthyid sarcopterygian fish from the Lower Permian (Autunian) of the Saar-Nahe Basin, Germany". Geobios. 45 (2): 241–248. Bibcode:2012Geobi..45..241W. doi:10.1016/j.geobios.2011.03.002.
  3. ^ a b "PBDB Taxon". paleobiodb.org. Retrieved 2024-12-16.
  4. ^ Borgen, Ulf J.; Nakrem, Hans A. (2016). Morphology, phylogeny and taxonomy of osteolepiform fish. Fossils and Strata. Wiley-Blackwell. doi:10.1002/9781119286448. ISBN 978-1-119-28643-1.
  5. ^ Cleveland Museum of Natural History; History, Cleveland Museum of Natural (1967). Kirtlandia. Vol. 1–29. Cleveland, Ohio: Cleveland Museum of Natural History.