Original paper

A new hybodontid shark (Chondrichthyes, Hybodontiformes) from the Lower Jurassic Posidonienschiefer Formation of Dotternhausen, SW Germany

Maisch, Michael W.; Matzke, Andreas T.

Abstract

A new genus and species of hybodontid shark, Crassodus reifi, is described from the upper Falciferum Zone of the Posidonienschiefer Formation (Lower Toarcian) of Dotternhausen, Baden-Württemberg, southwestern Germany. The type and only specimen comprises the Meckelian cartilages, palatoquadrates, remains of the labial cartilages and branchial skeleton as well as a large portion of the dentition. Comparison to other hybodontids shows a strong resemblance to Hybodus delabechei from the Sinemurian–Pliensbachian (?Toarcian) of Western Europe. H. delabechei is possibly a member of the new genus Crassodus but needs reinvestigation. Crassodus reifi and "Hybodus" delabechei deviate strongly in the characters of their dentition from the type species of the genus Hybodus, H. reticulatus Agassiz, 1837. The new genus Crassodus most probably represents a rather basal hybodontine hybodontid, whereas Hybodus sensu stricto is more closely related to other derived hybodontine genera with longicone, high-crowned teeth, such as Priohybodus, Planohybodus, Meristiodonoides and Secarodus.

Keywords

posidonienschiefer formationlower jurassictaxonomyhybodontiformescranial morphologydental morphology