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Extensive studies on fish diversity in Lakshadweep waters began with Jones and Kumaran’s in 1964. Reports after these authors were sparse and sporadic until the turn of this century. Although recent reports have increased the tally, targeted studies are lacking, and there is a possibility of listing more species for this region. Studies on the diversity and abundance of fishes are due, given the atoll system undergoing rapid changes: structural decline due to several bleaching related coral mortality events, changes in the seagrass meadows, and the increase in fishing reef-associated species. These circumstances call for a revised checklist of fishes for this region, for the latest dates back to 1991. Thus, we present an inventory of ichthyofauna of Lakshadweep atolls based on published literature and incorporating 15 new species records identified through a rapid survey. The new species records for this region are presented here with the diagnostics of these species. The checklist shows 856 species of 432 genera, 43 orders, and 144 families known from these islands, including 16 freshwater forms. 49.3% of the contribution is from 14 fish families having > 15 species each, while the remainder 131 families contributed 52.5%, which have < 15 species. About 154 species belonging to 12 families are known to contribute to the commercial fisheries of these islands. The new records reported in this work for this region are found in the Maldives, and Sri Lanka proves the zoogeographical affinity of these two regions with the Lakshadweep archipelago.

The Indian swellshark Cephaloscyllium silasi is a poorly known deep water scyliorhinid (Carcharhiniformes) shark described from the south-west coast of India (off Kollam). Since the original description, reports of this species are absent due to rarity of specimens. This paper presents the first report of its egg case and also provides detailed morphological data about C. silasi based on recently collected materials.

The composition, species richness and diversity of a coastal fish assemblage from the Kalpakkam coast of south-east India are described along with temporal distribution patterns related to seasonal fluctuations in dissolved oxygen, salinity, pH, chlorophyll-a, phytoplankton and zooplankton species richness and density. A total of 244 fish species belonging to 21 orders, 87 families and 163 genera were recorded. The fish assemblage was dominated by reef-associated species, followed by demersal species. The majority of the species (63%) are widely distributed in the western Indo-Pacific as well as in the central Indo-Pacific. Jaccard's coefficient analysis showed three distinct seasonal patterns of fish occurrence: pre-monsoon (PrM), monsoon (M) and post-monsoon (PoM). The maximum number of species was during the PrM period, followed by the PoM and M periods. Species occurrence analysis showed Sardinella longiceps to be dominant during PrM and M periods, Leiognathus dussumieri during the M period and Secutor insidiator and Secutor ruconius during the M and PoM periods. Canonical correspondence analysis indicated that salinity and rainfall were the two most influential environmental factors strongly correlated with temporal variation in the fish assemblage. The physico-chemical conditions, in combination with factors such as greater food availability and shelter, might control the seasonal local distribution of the ichthyofauna in these Indian coastal waters.