Ammonitenfauna und Stratigraphie im höheren Nor (Alaun, Trias) der Tethys aufgrund neuer Untersuchungen in Timor

This paper is a revision of the trachyostracous ammonoid fauna of the Himavatites columbianus zone from Timor, which has not been treated for more than fifty years. The basis for the revision was a collection made in spring 1975 at the classic locality Baun (Timor). The material collected in Timor is derived from blocks in Hallstatt-Limestone facies of maximum size 4 m '. The total thickness of the Columbianus zone is about one metre. The described fauna of trachyostracous ammonoids consists of 90 species which are distributed in 29 genera. Two genera and five species are newly described. The systematics is based on the "Treatise" (1957) and on the publications of TOZER (1971) and KRYSTYN (1978). Following the idea of KRYSTYN, ammonoids with an ammonitic suture and denticulated internal lobe, are seperated from the Ceratitina HYATT, 1884 and placed into the suborder Trachyceratina KRYSTYN, 1978. On the basis of this collection in the Hallstatt Limestone of Timor it was possible to establish that the higher Middle Norian is represented in the Tethys, as in British Columbia by the Himavatites columbianus zone (cornp. TATZREITER, 1978). A division of the Columbianus zone (sensu TOZER) is now proposed. The lower part (beds 12-15) far which the name Columbianus zone sensu stricto was formerly (TATZREITER 1978, 113, 115) used becomes now Himavatites hogarti zone (Alaun 2). Far the upper part (beds 16-18; formerly subzones III, IV) the name Halorites macer zone (Alaun 3) is proposed.