DICTYOCONUS ARABICUS HENSON (FORAMINIFERIDA) FROM THE LATE BARREMIAN OF THE LHASA BLOCK (CENTRAL TIBET)

Abstract

The orbitolinid  foraminifer Dictyoconus arabicus Henson is described for the first time from the Tibetan plateau (Coqen-Gerze road, Lhasa block, Central Tibet). A discussion of the principal published data reveals that this species occurs in the Late Barremian, probably ranging to the Early Aptian. The intraspecific evolutionary degree of the studied specimens indicates a Late Barremian age. This dating leads to the conclusion that the Cretaceous marine ingression in the Lhasa block took place during the same time interval.