Sudeepta Biswas

Imprint of monsoonal patterns on the fish assemblage in coastal waters of south-east India: a case study.

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. Jaccards 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.

Larval abundance and its relation to macrofouling settlement pattern in the coastal waters of Kalpakkam, southeastern part of India

The present work revealed that salinity, water temperature, and food availability were the most crucial factors affecting the abundance of larvae and their settlement as macrofouling community in the coastal waters of Kalpakkam. Quantitative as well as qualitative results showed that late post-monsoon (April–May) and pre-monsoon (June–September) periods were found to be suitable periods for larval growth, development, and survival to adult stages for most of the organisms. Clustering of physico-chemical and biological (including larval and adult availability) data yielded two major clusters; one formed by northeast (NE) monsoon months (October–January) and the other by post-monsoon/summer (February–May) months, whereas; pre-monsoon months (June–September) were distributed between these two clusters. Among all the major macrofouler groups, only bivalves established a successful relationship between its larval abundance and adult settlement. Principal component analysis indicated good associations of bivalve larvae with polychaete larvae and adult bivalves with adult barnacles. However, biotic relation between ascidians and bryozoans was observed both in the larval as well as adult community.

First Record of Eleven Reef Inhabiting Fishes from Tamil Nadu Coast of India, Bay of Bengal

Kalpakkam coast is an important strategic region reflecting the general diversity of Tamil Nadu (TN) coastal waters. In a recent inventory of fish survey conducted along this coast, we discovered 316 coastal fishes, of which >150 are reef fishes. The present paper describes the report of eleven reef-associated fishes new to the TN coast of Bay of Bengal viz. Torpedo sinuspersici Olfers, Himantura gerrardi (Gray), Gymnothorax meleagris (Shaw), Scorpaenodes guamensis (Quoy & Gaimard), Seriola rivoliana Valenciennes, Caesio cuning (Bloch), Nemipterus zysron (Bleeker), Parascolopsis eriomma (Jordan & Richardson), Abudefduf sordidus (Forsskal), Istiblennius edentulus (Forster & Schneider) and Canthigaster solandri (Richardson); out of which four (Gymnothorax meleagris (Shaw), Abudefduf sordidus (Forsskal), Istiblennius edentulus (Forster & Schneider) and Canthigaster solandri (Richardson)) are new to the Bay of Bengal coast of Indian mainland.

New records of four reef-associated fishes from east coast of India

First records of: viper moray, Enchelynassa canina (Quoy et Gaimard, 1824); v ermiculated blenny, Entomacrodus vermiculatus (Valenciennes, 1836); cardinalfish, Apogon fleurieu (Lacepede, 1802); and orange- lined cardinalfish, Archamia fucata (Cantor, 1849) in the waters along the east coast of India are herewith docu- mented. This record increases the knowledge on the richness of the Indian marine reef-associated fauna and may suggest a range extension of the geographical distribution of the mentioned species from the western Indian waters t o east coast of India.

First record of the Evermann’s snake eel, Ophichthus lithinus (Actinopterygii: Anguilliformes: Ophichthidae), from northern Indian Ocean

A little known species of snake eel, Ophichthus lithinus (Jordan et Richardson, 1908), is reported for the first time from the east coast of India, Bay of Bengal based on two specimens 632 and 720 mm in total length, collected respectively at Digha, West Bengal and Kalpakam, Tamil Nadu, India. This is the first attempt to pro - vide a detailed description of the species from the Indian Ocean. The presently reported findings constitute an extension of the known distributional range of this species from the Western Pacific to the eastern coast of India .