Cretaceous-Paleogene coprolite (fossilized faecal matter) records are significant in terms of providing direct palaeobiological evidence (from inclusions) in order to understand the diet of producer animal(s). In the past >150 years, research investigations (in India) have focussed on the Maastrichtian Type-A coprolite morphotype. Consequently, little information is available on the overall assemblage of Indian Maastrichtian vertebrate coprolites in terms of their morphological diversity, chemical composition, biotic-abiotic inclusions in the context of producer linkage(s) and geographic distribution within the Deccan volcano-sedimentary infra- and intertrappean deposits of India. Therefore, we present a detailed record of a coprolite assemblage from the Maastrichtian intertrappean deposits of Lotkheri, central India. This coprolite assemblage comprises five morphotypes based on their geometry, surface, and internal textures. Morphological considerations and biotic inclusions suggest that reptiles were the most likely producers of these ichnofossils. The associated faunal remains of reptiles (mainly chelonians and crocodilians) support this hypothesis. Dentalites or bite traces of Garfish (genus Lepisosteus) observed on the external surface of a few coprolite specimens (studied herein) are a rarity in the global fossil records. The analytical evidence confirm the phosphatic composition of the coprolites with the unique presence of three distinct morphologies (i.e. spherical, rods, and needles) of apatite crystals. Finally, we provide the chemical nature and plausible mechanism of apatite crystal formation via the chemical processes undergoing during the biomineralization of these crystals observed within coprolites.
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