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The dental morphology of the pycnodontid fish †Stemmatodus rhombus (Agassiz, 1844) from the Lower Cretaceous (lower Barremian) of southern Italy is described in detail. SEM pictures of vomerine and prearticular teeth are provided for the first time allowing the comparison with other Early Cretaceous pycnodonts, which are only known from isolated dental remains. The dentition of †Stemmatodus rhombus consists of incisiform grasping teeth on the paired premaxillae and dentaries and crushing teeth on the unpaired vomer and paired prearticulars. The vomerine teeth are arranged in five longitudinal rows, which display symmetry with a distinct median principal and two lateral rows. The prearticular bears three longitudinal rows. Teeth of the main row are much wider than those of the lateral ones. The tooth crowns are rather flat and expose a shallow apical depression, which is surrounded by a ring of widely-spaced small tubercles. The ornamentation and arrangement of teeth distinguishes dentitions of †Stemmatodus from all other pycnodonts. The wear pattern of the teeth is evaluated and the significance of the dental morphology in pycnodont taxonomy is discussed. In addition, the systematic position of †Stemmatodus is discussed.

The first Late Jurassic selachian and actinopterygian fishes of Tendaguru in Tanzania were collected by the German-Tendaguru expedition in [1909][1910][1911][1912][1913]. They are represented mainly by occasional teeth of a neoselachian (Sphenodus) and several specimens of a neopterygian (Lepidotes). New material collected by the German-Tanzanian Tendaguru expedition in 2000 includes additional selachians recovered from clay stones at site Dwa 5a and isolated actinopterygian remains. At least three hybodonts (Hybodus sp., Hybodontidae indet., Lonchidion sp.) and a new neoselachian batoid are presented here. This assemblage is endemic to Tendaguru. A new batoid genus and species, Enguibutis schultzei, is described, which is the oldest record of a ray from Gondwana. The actinopterygians are represented by scarce and disarticulated scales of Lepidotes, 'pholidophoriform'-like scales, and teleostean vertebrae. This material includes new biogeographic records for Africa. In addition, a synopsis of Jurassic fishes from Africa is presented. ZusammenfassungDie Fischfauna aus dem Oberjura von Tendaguru ist bisher nur unzureichend bekannt. Das erste Material, das von der Deutschen Tendaguru-Expedition (1909)(1910)(1911)(1912)(1913) gesammelt wurde, besteht fast nur aus einigen wenigen isolierten Zahne des Haies Sphenodus und mehreren Exemplaren des Actinopterygiers Lepidotes. Neue Funde, die wahrend der Deutsch-Tansanischen-Tendaguru-Expedition im Jahre 2000 geborgen wurden, erlauben es, mehrere Taxa zu beschreiben, die aus dem Oberjura Afrikas noch nicht bekannt waren. Anhand von Zahnen konnten mindestens drei zu den urspriinglichen Hybodontiern zahlende Taxa (Hybodus sp., Hybodontidae indet., Lonchidion sp.) nachgewiesen sowie ein fur Tendaguru neuer Rochen (Enguibutis schultzei n. gen. and n. sp.) festgestellt werden. Actinopterygier sind durch wenige und disartikulierte Schuppen von Lepidotes und einer 'pholidophoriden'dhnlichen Form sowie durch Wirbel von Teleosteern vertreten. Das ,neue Material gibt wichtige Hinweise auf die palaobiogeographische Verbreitung der spatjurassischen Fische. Es wird ein Uberblick uber die bisher bekannten jurassischen Fischfaunen Afnkas gegeben.Schliisselworter: Fische, Enguibutis schultzei n. gen. und n. sp.,

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