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Traces of predation by drilling gastropods and peeling crabs provide important insights about predator-prey interaction in ecological as well as evolutionary times. Predation on turritelline gastropods, in this context, has been frequently discussed in literature. Here, we have estimated the intensity of predation (both drilling and peeling) on Recent turritelline gastropods from the Indian subcontinent, which has been underrepresented in previous studies. Our samples include our own collections from several Indian coasts as well as a vast collection which was locked in the archive of the Zoological Survey of India (ZSI) in Kolkata for the past 150 years. It includes samples from different parts of the Indian subcontinent as well as from many other countries. Drilling frequency (DF) of Indian turritelline species is low compared to average values of global data. We suggest that this is mainly because most of the Indian species are larger (> 4 cm) than species living elsewhere. Smaller species show higher DF and lower values of peeling frequency. Size selectivity of drill holes shows both intra-and interspecific variation. Shell thickness and ornamentation appear to be antipredatory in nature.We have compared our results with a revised global database. Distribution of intensity of predation shows latitudinal variation where both drilling and peeling frequencies increase towards the tropics.

Naticid taxonomy is in a state of flux owing to non-descript shell morphology and frequent convergence. Inadequate preservation of naticid body fossils has further complicated the matter in determining the true affinity and the exact time of origin of the clade. As a result, a plethora of classificatory schemes of naticid phylogeny and times of origin has been proposed. In many previous studies, true naticid affinities of fossils have been sought based on single or a few morphological characters, which are susceptible to poor preservation. In the present paper, we have attempted a holistic reappraisal of naticid taxonomy based on an extensive database of shell morphological characters and identified many distinct family- and subfamily-specific characters that survived fossilization. This approach has enabled us to identify three new naticid species from the Late Jurassic horizons of Kutch, India, thus extending back the time of origin of the family Naticidae by 30 Ma.Analysis of character matrix data reveals that the present species—Gyrodes mahalanobisi new species, Euspira jhuraensis new species, and Euspira lakhaparensis new species—belong to two subfamilies, Gyrodinae and Polinicinae. The occurrence of typical naticid drill holes on various coeval gastropod and bivalve taxa along with these body fossils provides strong supporting evidence for the naticid affinity of these forms.UUID http://zoobank.org/94188d64-075b-4bd0-8303-1ce9a0d86eb0

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Turritellid gastropods are important components of many Cretaceous–Recent fossil marine faunas worldwide. Their shell is morphologically simple, making homoplasy widespread and phylogenetic analysis difficult, but fossil and living species can be recognized based on shell characters. For many decades, it has been the consensus that the oldest definite representatives of Turritellidae are from the Lower Cretaceous, and that pre-Cretaceous forms are homeomorphs. Some morphological characters of the present turritelline species resemble those of mathildoids, but many diagnostic characters clearly separate these two groups. We here describe and/or redescribe—based on examination of more than 2600 near complete specimens—four species from the Upper Jurassic Dhosa Oolite Member of the Chari Formation in Kutch, western India, and demonstrate that they are members of Turritellidae, subfamily Turritellinae, on the basis of diagnostic characters including apical sculptural ontogeny (obtained from SEM study), spiral sculpture, and growth line patterns. The four species are in order of abundance, Turritella jadavpuriensis Mitra and Ghosh, 1979; Turritella amitava new species; Turritella jhuraensis Mitra and Ghosh, 1979, and Turritella dhosaensis new species. The turritelline assemblages occur only on the northeastern flank of the Jhura dome (23°24’47.57”N, 69°36’09.26”E). Age of the Dhosa Oolite has recently been confirmed based on multiple ammonite species. All these points indicate that these fossils are the oldest record of the family Turritellidae—by almost 30 million years—in the world.