Ammonites from the Oxfordian (Bifurcatus zone) strata of Gangta Bet, Kachchh, Western India

Gangta Bet, an islet situated in the salt marshes of the Great Rann of Kachchh, western India, is composed of Jurassic strata containing a rich fauna of Upper Oxfordian ammonites which are very rare in other parts of the Kachchh Basin. A detailed bed-by-bed collection yielded 148 ammonites belonging to 21 taxa which are briefly described and illustrated. The assemblage is strongly dominated by members of the genus Perisphinctes Waagen, 1869, which are excellent guide fossils enabling intrabasinal and intercontinental correlations e.g., with the ammonite zonation of Europe. While the oldest beds on the Gangta Bet did not yield ammonites indicative of a certain biozone, most of the recorded taxa can be assigned to the Bifurcatus Zone (Stenocycloides and Grossouvrei subzones) of the Upper Oxfordian.