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The shallow marine sedimentary sequence of the Jaisalmer Basin exhibits one of the important and well-developed Tithonian sedimentary outcrops for western India. The ichnology and ichnofabric of the lower part of Bhadasar Formation (i.e., Kolar Dongar Member) belonging to Tithonian age are presented and discussed. The Kolar Dongar Member represents a shallow marine succession that contains 16

The Guneri dome, situated in the Western Kachchh, is famous for its prominent exposures of Lower Cretaceous sandstone-dominated Guneri member belonging to the Bhuj formation. The ichnogenus Balanoglossites Ma ¨gdefrau, 1932 is reported for the first time from the Indian subcontinent and is represented by B. triadicus and B. ramosus, occurring in association with the tear-shaped boring Gastrochaeonolites. These trace fossils occur as a part of two, laterally extensive Glossifungites ichnofacies surface, representing omission suite assemblage. The detailed analysis of the trace fossil Balanoglossites along with lithofacies analysis suggests that it belongs to the Glossifungites ichnofacies surface and this trace fossil bearing surface corresponds to the Lower Cretaceous regressive phase that marks the unconformity of other parts of the Kachchh basin.

A palaeocommunity of large Conichnus conicus, a conical, cone-in-cone shaped burrow, created by sea anemones, occurs in medium-grained, crossbedded, well-sorted sandstone in the middle part of the Cretaceous Guneri Member of the Bhuj Formation in India. The trace fossil Conichnus is considered to be a common element of the Skolithos ichnofacies and is interpreted to reflect equilibrium movement in response to substrate aggradation. In the present study, three different varieties of Conichnus conicus are distinguished based on morphology and internal fabric. Community dynamics and burrowing behavior are revealed by inter-burrow relationships, burrow initiation levels and sedimentology. Three types of behavior are envisaged: retrusive equilibrium, protrusive equilibrium response, and escape behavior. Palaeocommunity dynamics show that the tracemakers consisted of only adult organisms that initiated burrows during neap tides and are adapted to feed effectively during weak flow conditions. The occurrence of Conichnus palaeocommunity in the Guneri Member indicates the tidal conditions in a fully marine setting. Results presented herein may aid in the understanding of palaeocommunity dynamics in other shallow marine sequences.