Diademodus hydei, a new fossil shark from the Cleveland Shale.
Open Access
- 1 February 1951
- journal article
- Published by Wiley in Journal of Zoology
- Vol. 120 (4) , 683-697
- https://doi.org/10.1111/j.1096-3642.1951.tb00672.x
Abstract
Summary.: Diademodus hydei, a new genus and species of shark from the Cleveland Shale, is described and figured from the holotype in the Cleveland Museum of Natural History. About 40 centimetres in length, the fish is an adult male with well‐developed claspers; it shows a combination of hybodont and cladoselachian characteristics. The teeth are many‐cusped and bilaterally symmetrical, with the outer cusps longer than the inner; they approach more closely to the sculpturing of the scale pattern than in orther primitive sharks. A comparison with the contemporaneous Cladoselache and Ctenacanthus clarki suggests that Diademdus is an early and not distant offshoot from the primitive chondrichthyan stock, the main line of which led through Ctenacanthus and the hybodonts to the modern elamobranchs; Cladoselache is a specialized side line of this main stock and is not an appropriate ancestral type for the Chondrichthyes.Keywords
This publication has 6 references indexed in Scilit:
- XV.—The Paired Fins of PlacodermsTransactions of the Royal Society of Edinburgh, 1947
- THE EARLY EVOLUTION AND RELATIONSHIPS OF THE ELASMOBRANCHSBiological Reviews, 1939
- II - The Acanthodian fishesPhilosophical Transactions of the Royal Society of London. B, Biological Sciences, 1937
- The Structure and Affinities of the Fossil Elasmobranch Fishes from the Lower Carboniferous Rocks of Glencartholm, EskdaleJournal of Zoology, 1936
- Studies on the structure & development of vertebratesPublished by Biodiversity Heritage Library ,1930
- IV. On Cladodus Neilsoni (Traquair), from the Carboniferous Limestone of East KilbrideTransactions of the Geological Society of Glasgow, 1898