A new Jurassic cow shark (Chondrichthyes, Hexanchiformes) with comments on Jurassic hexanchiform systematics

作者：Kriwet Juergen^*; Klug Stefanie

来源：Swiss Journal of Geosciences, 2011, 104(S1): S107-S114.

DOI：10.1007/s00015-011-0075-z

• Notidanus serratus
• Hexanchus? wiedenrothi
• Crassodontidanus gen. nov.
• Crassonotidae fam. nov.
• Jurassic
• Nusplingen Plattenkalke

A new taxon, aEuro Crassodontidanus gen. nov. of Hexanchiformes (cow sharks) from the Jurassic of Germany is described. It is characterized by peculiar teeth combining apomorphic (serrated mesial cutting edge of the main cusp) and plesiomorphic features (deep root with convex mesial and distal margins in labial and lingual views; protruding lingual root bulge). This character combination readily distinguishes members of the new taxon from all other known extant (Heptranchias, Hexanchus, Notorynchus) and extinct (aEuro Gladioserratus, aEuro Notidanodon, aEuro Notidanoides, aEuro Pachyhexanchus, aEuro Paraheptranchias, aEuro Weltonia) hexanchiforms. Currently, two species, aEuro C. serratus (type species; Late Jurassic, Late Kimmeridgian of Nusplingen, South Germany) and aEuro C. wiedenrothi (Early Jurassic, Early Pliensbachian of Gretenberg (Hanover), North Germany) are assigned to this taxon. aEuro Crassodontidanus gen. nov. is member of aEuro Crassonotidae fam. nov. and sister to aEuro Notidanoides Maisey, 1986 and aEuro Pachyhexanchus Cappetta, 1990. We consider aEuro Notidanus amalthei Oppel, 1854 from the Pliensbachian of South Germany, aEuro Notidanus insignis Seguenza, 1887 from the Oxfordian of Sicily (Italy) and aEuro Notidanus wagneri Agassiz, 1843 from the Early Tithonian of Solnhofen (South Germany) nomina dubia and nomina nuda, respectively. The family aEuro Crassonotidae comprises plesiomorphic hexanchiforms ranging from the Sinemurian (Early Jurassic) to the Hauterivian (Early Cretaceous).

• 出版日期2011-12