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Studies on the Paleozoic selachian genus Ctenacanthus Agassiz. No. 1, Historical review and revised diagnosis of Ctenacanthus, with a list of referred taxa

by: Maisey, John G

Publication date: 1981

Topics: Ctenacanthus, Chondrichthyes, Fossil, Fishes, Fossil, Paleontology, Paleontology -- Paleozoic

Publisher: New York, N.Y. : American Museum of Natural History

Collection: americanmuseumnaturalhistory; biodiversity

Contributor: American Museum of Natural History Library

Language: English

Rights: http://biodiversitylibrary.org/permissions

Rights-holder: American Museum of Natural History Library

Volume: no. 2718

22 p. : 26 cm

"Ctenacanthus Agassiz is a genus of elasmobranch, originally recognized by its dorsal finspines but now known from more complete remains. However, many other fossils, including isolated spines and complete fish, have been included in Ctenacanthus, although the spines differ from those of the type species, C. major, and from other presumably related species. Earlier diagnoses of Ctenacanthus are critically reviewed and the significance of previous diagnostic changes is discussed. It is concluded that Ctenacanthus sensu lato is paraphyletic. Some spines previously assigned to this taxon resemble living elasmobranch finspines, whereas others resemble hybodontid finspines. The fish described by Dean as Ctenacanthus clarkii should be referred to C. compressus. Both C. clarkii and C. compressus finspines are sufficiently like those of C. major for these species to remain within the genus. Ctenacanthus compressus is the only articulated Paleozoic shark so far described which can be assigned to Ctenacanthus. Ctenacanthus costellatus finspines are not like those of C. major, but instead resemble Sphenacanthus spines. Goodrichthys eskdalensis may be closely related to Ctenacanthus"--P. [1]

Title from caption

"November 19, 1981."

Includes bibliographical references (p. 21-22)

Abstract: 'Ctenacanthus Agassiz is a genus of elasmobranch, originally recognized by its dorsal finspines but now known from more complete remains. However, many other fossils, including isolated spines and complete fish, have been included in Ctenacanthus, although the spines differ from those of the type species, C. major, and from other presumably related species. Earlier diagnoses of Ctenacanthus are critically reviewed and the significance of previous diagnostic changes is discussed. It is concluded that Ctenacanthus sensu lato is paraphyletic. Some spines previously assigned to this taxon resemble living elasmobranch finspines, whereas others resemble hybodontid finspines. The fish described by Dean as Ctenacanthus clarkii should be referred to C. compressus. Both C. clarkii and C. compressus finspines are sufficiently like those of C. major for these species to remain within the genus. Ctenacanthus compressus is the only articulated Paleozoic shark so far described which can be assigned to Ctenacanthus. Ctenacanthus costellatus finspines are not like those of C. major, but instead resemble Sphenacanthus spines. Goodrichthys eskdalensis may be closely related to Ctenacanthus'--P. [1].