Early Permian megaspores from Goutham Khani Open Cast Mine, Kothagudem Area, Godavari Graben, Telangana, India

Abstract

Early Permian megaspores are reported for the first time from the Barakar Formation of Index Seam, Goutham Khani Open Cast Mine, Kothagudem Area, Godavari Graben, Telangana, India. The megaspore assemblage includes three genera and ten species, namely Biharisporites spinosus, Biharisporites sp. A (in Tewari et al., 2009), Biharisporites sp., Jhariatriletes filiformis, Jhariatriletes sp., Singhisporites indica, S. nautiyalii, S. radialis, S. surangei and Singhisporites sp. Besides adding to the existing knowledge of megaspores from the Godavari Graben, the comparison of megaspores from the Goutham Khani Open Cast Mine with those of the other Indian Lower Gondwana basins, namely Damodar, Satpura, Wardha, South Rewa and other areas of the Godavari Graben reveals that majority of these differ in the presence of dense ornamentations on their exosporia. The previous records of megaspores from the late Permian of the Godavari Graben show dense spinate exosporia. Presence of such dense diverse spines on megaspores of this study indicates their early appearance during the Barakar Formation. An analysis of the developmental pattern of the exosporium architecture of Lower Gondwana megaspores in general, indicates that during the early Permian Talchir and Karharbari formations, the megaspores had simple outer layer with usually smooth, granulate, verrucate and sometimes baculate/connate ornamentations whereas, dense spinate exosporia were more common during Barakar and Raniganj formations indicating fresh water aquatic conditions. As such, the spinate megaspores of Kothagudem region also point towards terrestrial aquatic conditions.