Ostracods, plant tissues, and other inclusions in coprolites from the Late Cretaceous Lameta Formation at Pisdura, India: Taphonomical and palaeoecological implications

•First record of ostracods in Upper Cretaceous coprolites from Pisdura, India•Aquatic inclusions include diatoms, a charophyte, chrysophytes and sponge spicules.•Faecal inclusions and phosphate content suggest intentional or inadvertent omnivory.•The depositional setting indicates fluvio-lacustrine conditions.

A rich microbiota with distinctive plant fossils has been discovered in Type A morphotype coprolites from the Lameta Formation of Pisdura, in Maharashtra, India. Macerated fractions examined with scanning electron microscopy revealed seven ostracod taxa, (?Mongolianella sp., Cypridea (Pseudocypridina) sp., Cypridopsis sp., Eucypris sp., Gomphocythere sp., Gomphocythere paucisulcatus, and Paracypretta sp.), diatoms (Aulacoseira sp.), a charophyte (Microchara sp.), and sponge spicules. Abundant probable chrysophytes were also observed in thin sections of one of the coprolites. Most of the plant debris is unidentifiable, but recognizable tissues include gymnosperm tissues, a spore, cuticle, and leaf laminae replaced with silica. Chemical analyses reveal that the coprolites are phosphatic, with ~ 12.2 to 16.2 wt.% phosphorus. The microfossils support a Maastrichtian age and fluvio-lacustrine depositional conditions for the Lameta Formation at Pisdura. The unusual combination of a phosphatic composition with plant and microfossil dietary residues suggests that the ancient faecal producers were intentional or inadvertent omnivores.