Australodocus

Abstract: . The Late Jurassic (Tithonian) Tendaguru Beds of Tanzania yielded one of the richest sauropod faunas known, including the diplodocines Tornieria africana (Fraas, 1908) and Australodocus bohetii Remes, 2007, the only known representatives of their group on the southern continents. Historically, the holotypes and referred material of both taxa plus dozens of additional specimens had been subsumed under the term "Barosaurus africanus" (Fraas, 1908). Here, the taxonomic status of the referred elements is reviewed by evaluating the phylogenetic information content of their anatomical characters, in order to provide a firm footing for further studies (e.g. of morphometrics, histology, and phylogeny of the Tendaguru sauropods). Some of the material shows diplodocine synapomorphies and may belong to either Tornieria or Australodocus, while other specimens are diagnostic only on higher taxonomic levels (Diplodocidae, Flagellicaudata, or Diplodocoidea indet.). The isolated limb elements in most cases lack phylogenetically diagnostic characters. Generally, the "Barosaurus africanus" sample shows a substantial grade of morphological variation, and it cannot be ruled out that there are more flagellicaudatans represented in the Tendaguru material than the diplodocines and dicraeosaurids already known. doi: 10.1002/mmng.200800008

Abstract: A new genus and species of diplodocid sauropod (Sauropoda, Diplodocoidea), Australodocus bohetii, is described. The type material from the Upper Jurassic (Tithonian) Tendaguru Beds of Tanzania, East Africa, consists of two successive mid-cervical vertebrae. These vertebrae do not show the extreme elongation of the cervical vertebrae that is diagnostic for Tornieria, and, apart from proportional differences, exhibit four autapomorphic characters not seen in other diplodocids: (1) pleurocoel weakly developed; (2) ridge posterolateral to the anterior condyle strongly posteroventrally orientated; (3) triangular pneumatic cavity ventral to the prezygapophysis, enclosed by the lateral ramus of the centroprezygapophyseal lamina and an anteriorly extended prezygodiapophyseal lamina; and (4) prominent prezygapophyseal process pointed, laterally keeled and surpassing the prezygapophysis anteriorly. Australodocus bohetii is the second diplodocid known from Tendaguru, and thereby the second diplodocid known from Gondwana. This impedes the customary reference of isolated East African diplodocid material to Tornieria, which can now only be assigned to Diplodocidae indet. The find supports previously proposed vicariance models of diplodocid palaeobiogeography.