Ptyctodontid fishes (Vertebrata, Placodermi) from the Late Devonian Gogo Formation, Western Australia, with a revision of the European genus Ctenurella Ørvig, 1960

John A. LONG

en Geodiversitas 19 (3) - Pages 515-555

Published on 30 September 1997

A new, almost complete specimen of the ptyctodontid placoderm Campbellodus decipiens Miles et Young, 1977 enables description of the skull roof, trunk shield, visceral skeleton, pelvic girdle, dermal scale cover, and parts of the vertebral column. A new reconstruction of the head shield of Ctenurella gladbachensis Ørvig, 1960 from Bergisch-Gladbach permits this taxon to be generically defined from the Gogo species previously referred to that genus. The Gogo form is here referred to Austroptyctodus n.g. A new specimen of Austroptyctodus gardineri Miles et Young, 1977, together with new observations of Chelyophorus verneuili Agassiz, 1844 and Ctenurella gladbachensis Ørvig, 1960, shows new information for the endocranium, the hyoid arch and visceral skeleton, identifying the previously identified "metapterygoid" elements as paired nasal bones. The large visceral skeleton bone posterior to the jaw joint in ptyctodontids is here identified as an elongated interhyal.

Keywords :

Ptyctodontida, Devonian, Placodermi, Gogo, Australia, Austroptyctodus n.g., Ctenurella, Chelyophorus