Benthic foraminifera and ostracoda from the dalichai formation (Aalenian–Bajocian) at Telma-Dareh, Alborz Mountains, Northern Iran

Abstract

Aalenian-Bajocian benthic foraminiferal and ostracode assemblages of the Dalichai Formation (lithologic unit III) at Telma-Dareh, Alborz Mountains (northern Iran) are presented herein. Twenty-four foraminiferal taxa were identified, with the genera Reinholdella, Epistomina and Lenticulina as the dominant taxa. The dominance of r-selected strategists among foraminifera suggests the occurrence of stressing paleoenvironmental conditions, probably related to bottom-water oxygen levels, during the deposition of the studied strata. The foraminiferal assemblages studied herein are similar to other Boreal ones in paleobiogeographic terms. The ostracode assemblages present low abundance, low species richness and poor preservation, which did not allow any identification at species level. A possible record of Majungaella is briefly discussed due to its paleozoogeographic significance. Cytherella, Paracypris and Pontocyprella are the richest genera with two species each.