Despite extensive studies on mangrove ecosystems of Andaman and Nicobar Islands since the 1870s, knowledge of exact species composition is far from complete, and there is a lack of comprehensive locality data. The present study was designed to review the existing literature and to provide an updated checklist of the true mangrove species of the Islands. Preliminary surveys were carried out in seven regions (four from the Andaman group and three from the Nicobar group), and the specific survey sites for detailed study (n = 51) were selected based on representativeness, importance, and accessibility. During 2009During -2013, all the selected sites were visited, and mangrove species occurrence was recorded. At present, 25 true mangrove species distributed among 10 families and 14 genera were identified vis-à-vis 17 to 36 species reported in earlier studies. The discernible changes in species numbers from earlier studies could mainly be attributed to our exclusion of associated littoral vegetation and of species unlikely to be present among the true mangroves of the Islands. Given their limited geographical area, the low similarity index values between the Andaman and Nicobar Island groups ( ≤ 0.4) indicate a need for periodical surveys, as mangrove biodiversity is usually homogenous in regions where there are no impassable dispersal barriers. Further, regular updating of information on the extent and status of mangroves in the Islands is imperative not only to improve our understanding of phytogeography but also for better management and conservation.

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This study reports an updated checklist of marine shrimps found along the Indian coast, including the Lakshadweep and the Andaman & Nicobar Islands.  A total of 364 species classified under 128 genera belonging to the order Decapoda is reported, thus adding 27 species to the existing checklist of 337 species.  Marine shrimps are classified under two suborders of the order Decapoda, viz., Dendrobranchiata and Pleocyemata, and the two suborders account for 155 (42.6 %) and 209 species (57.4 %) of these 364 species, respectively.  Pleocyemata is represented by three infraorders, viz., Axiidea, Caridea and Stenopodidea, while Caridea has a maximum of 199 reported species. Among the 12 superfamilies, Penaeoidea contributed to 38.13% (135 species) followed by Paleaemonidea with 18.07% (64 species).  All other superfamilies were found to contribute less than 12%.  Superfamilies, Bresilloidea and Psalidopodoidea had only single species representatives (0.28% each).  The final list was compiled after reviewing all existing literature including monographs, catalogues, checklists, websites and fishery reports. The scientific names were validated with the World Register of Marine Species (WoRMS) database.  A total of 25 issues were identified from the previous checklist out of which 19 species have been updated with the correct, accepted names and six species have been removed from the previous list.

<p>The genus <em>Chondrilla</em> is reported from the Andaman group of Islands off Havelock Island for the first time, with two species, <em>C. grandistellata</em> and <em>C. australiensis</em> in this study.  This genus has previously been reported and represented by four species in Indian waters viz., <em>Chondrilla mixta, C. sacciformis, C. kilakaria </em>and<em> C. australiensis.</em> <em>C. australiensis</em> is light brown to reddish-brown in colour; encrusts primarily on live boulder corals; contains oxyasters measuring 14.8-(18.5)-22.2 µm and spherasters measuring 17.3-(26)-29.7 µm. <em>C. grandistellata</em> is tan or brown in colour with unevenly distributed white speckles; Contains large spherasters that measure 106.3-(143.3)-175.6 µm.  In this study it is suggested that <em>C. sacciformis</em> specimens reported previously from India may be <em>C. grandistellata</em>; this probable conspecificity is also discussed. </p><div> </div>

The corals in Andaman and Nicobar Islands suffered extensive bleaching during April 2010 to the extent of 60-70 % due to elevated sea surface temperature (SST) and a significant portion of that is hitherto dead. This study evaluates the degree of recovery of the coral reefs and reef fishes, a year after the event. Line intercept transect (LIT) surveys were conducted in three sites, namely, North Bay, Tarmugli and Chidiyatapu for assessing coral cover together with visual census of reef fishes along the same transects. It was observed that all sites were quite badly affected during the bleaching period with more than 95 % of the corals being fully or partially bleached. Out of the bleached corals, only 54 % recovered at North Bay, whereas Tarmugli and Chidiyatapu exhibited 81 and 86 % recovery, respectively. The collapse of coral reef systems affected the abundance and diversity among fish species. Due to recovery and new recruitment of corals, live coral cover has increased, and consequently,, abundance of fishes seems to have increased. Understanding the associations of fishes and corals could possibly lead to selection of certain species of fishes as indicators of reef health. The results of the study lead to the hypothesis that fishes, especially those belong to the families, Chaetodontidae, Pomacentridae, Acanthuridae and Scaridae can be potential indicators of reef health.

The pantropical seagrass

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