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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. [ABSTRACT FROM AUTHOR]

Reports of synchronous spawning in corals of Lakshadweep reefs, India have been purely anecdotal. To understand factors that underlie coral spawning in Lakshadweep, we studied four Acropora species (A. muricata, A. cytherea, A. hemprichii and A. nobilis) in Kavaratti atoll from February to March 2018. These species were observed in situ for oocyte maturation, and the larvae of species A. muricata and A. cytherea were assessed for survival and settlement rates. Observations on oocyte maturation indicated possible spawning closer to the immediate full moon of species in which 7-28% of the colonies had mature oocytes. Thus, A. muricata, A. cytherea and A. hemprichii spawned on 25 and 26 February 2018, demonstrating multi-specific synchronous spawning, whereas A. nobilis spawned on 21 March 2018. Larval survival rates revealed a steep die-off beginning on day 12 postspawning and maximum survival up to 24-27 days. Settlement occurred between 12 and 20 days for A. muricata and between 12 and 22 days for A. cytherea. The comparatively low survival duration and fewer larvae surviving for settlement show that maximum settlement could be heavily compromised. However, the study reveals that the comparatively late onset of settlement (from day-12, post-spawning) and the broader settlement window of 8-10 days could allow room for long-distance dispersal of larvae. Further studies on this front are required to gather a better picture. [ABSTRACT FROM AUTHOR]