Late Bajocian and Bathonian (Middle Jurassic) ammonites from the Dalichai Formation north of Damghan (Alborz, North Iran)

From two outcrops north of Damghan (eastern Alborz Mountains) Late Bajocian and Bathonian ammonites are described. The fauna comprises the families Haploceratidae, Oppeliidae, Stephanoceratidae, Morphoceratidae and the subfamilies Hecticoceratinae, Cadomitinae, Garantianinae and Parkinsoniinae. The families Phylloceratidae, Lytoceratidae and Perisphinctidae are not considered in detail in this study. The ammonites are mostly concentrated in a few metres thick, violet to brick-red nodular limestone and marls in "Ammonitico Rosso" facies. The ammonite fauna shows close relationships to those from epicontinental seas, bordering the northern margin of the western Tethys, and takes an intermediate position between the Subboreal and Submediterranean provinces.