Paleogeographic implications of the Shanita-Hemigordius fauna （Permian foraminifer） in the reconstruction of Permian Tethys

摘要

The Permian foraminifer Shanita is a genus of special paleobiogeographic importance. Current data indicate that this genus occurs in peninsular Thailand, Shan States of Burma, western Yunnan and northwestern Tibet of China, south Pamir of Tajikistan, South Afghanistan, Kuh-e Gahkum area of lran, Transcaucasus, Pinarbasi area of Turkey, and the Saiq Plateau of Oman. Studies also show that several species of Hemigordius usually coexist with Shanita, and form a peculiar Shanita-Hemigordius fauna. Localities of the Shanita-Hemigordius fauna that have been found hitherto are confined on Gondwanaderived blocks, which constitute a strip starting from peninsular Thailand and extending northwestwards and westwards to Turkey. This fauna is considered as another Permian palaeontological marker of marginal Gondwana environment.