An ammonite fauna from the upper Abderaz Formation of Kuh-e-Bul in the northwestern part of the
Koppeh Dagh (Iran) is described and illustrated. The collection of 30 specimens is assigned to seven
species, all of which are recorded from Iran for the first time: Pseudophyllites indra (Forbes, 1846),
Pachydiscus (Pach.) haldemsis (Schlüter, 1867), Patagiosites stobaei (Nilsson, 1827), Menuites wittekindi
(Schlüter, 1876), Glyptoxoceras retrorsum (Schlüter, 1872), Lewyites elegans (Moberg, 1885) and Trachyscaphites
spiniger (Schlüter, 1872). This fauna is of a typical Boreal character, with all taxa having been
described from northwest Europe originally. The stratigraphic range indicated by the ammonites is lower
upper Campanian, below the first occurrence of Nostoceras (Bostrychoceras) polyplocum (Roemer, 1841)
and probably above the last occurrence of Hoplitoplacenticeras (H.) vari (Schlüter, 1872). A nannofossil
sample from the ammonite-bearing interval corresponds to the upper Campanian nannofossil zone
UC15/CC22. Thus, on the basis of both ammonites and calcareous nannofossils, the upper Abderaz Formation
is shown to be younger than assumed previously.
کلید واژگان :
Upper Cretaceous Middle East Cephalopods Calcareous nannoplankton Palaeobiogeography Biostratigraphy
