Discovery of carbonaceous remains from the Neoproterozoic shales of Vindhyan Supergroup, India

Abstract

Neoproterozoic gray to dark gray carbonaceous shales belonging to the Bhander Group exposed in and around Maihar and Nagod areas, Satna district, Madhya Pradesh, contains an exceptionally well preserved, diversified fossils represented by both planktic and benthic meso-megascopic (millimeter to centimeter in dimension) and multicellular metaphytes. The fossils are of varied shape viz., leaf like thalloid films, palmate, straight to curve, with/without holdfast. Some of them are dichotomously branched and compactly entangled thin filaments, including possible reproductive structures. Out of eighteen algal taxa described assemblage includes fifteen genera and sixteen species belong to known metaphytes interpretable as multicellular eukaryotes. The assemblage comprises thalloid algae referable to Aggregatosphaera miaoheensis, Baculiphyca taeniata,Doushantuophyton lineare, Daus-hantuophyton cometa, Enteromorphites siniansis, Eopalmaria pristina, Flabellophyton lantianensis, Glomulus filamentum,Huangshanophyton fluticulosum, Jiangchuania taeniphylla, Konglingiphyton erecta, Palaeochorda vindhyansis, Sitaulia minor and discoidal carbonaceous films of Churaria cir-cularis, Longfengshania ovalis, Protoarenicola baiguashanensis, Protoconites minor and Tawuia dalensis. Amongst these two taxa viz. S. minor gen. et. sp. nov. and P. vindhyansis gen. et. sp. nov. Presence of holdfasts and branches indicates advent of complexity in Neoproterozoic life. It is assumed that they preferred shallow water where dissolved nutrients and congenial stable environment. The multicellular metaphytes are comparable to modern algae belonging to Rhodophyta, Phaeophyta, Xanthophyta and Chlorophyta. This assemblage closely resembles the known assemblages of the equivalent sediments (Cryogenian to Early Ediacaran age) of Miaohe biota (China) and White Sea Biota, central Ural (Russia). Key words: Multicellular, eukaryotes, metaphytes, Bhander group, Vindhyan Supergroup.