Myctophid fishery along the Kerala coast with emphasis on population characteristics and biology of the headlight fish, Diaphus watasei Jordan & Starks, 1904

Myctophids form bycatch in deep sea shrimp trawls with an annual average catch of 2668 t during 2009 - 2011 in Kerala coast. Fishery occurred almost round the year with peak during November - February. Fishery and biology of the dominant species, Diaphus watasei was monitored. Peak spawning and recruitment of the species was during January-August. Growth parameters L∞ and K are estimated as 15.06 cm and 0.8 per year respectively. These values indicate that the species growth is relatively fast. Natural mortality estimate (M) is 1.21, total mortality (Z) 1.68 and fishing mortality (F) 0.47. The exploitation rate (E) is low being 0.279. These indicate that the stock is at its initial stage of exploitation and there is large scope for enhancing their commercial exploitation. The stock abundance, biomass and distribution of the resource need to be assessed. These factors have to be taken into consideration while planning for exploitation of myctophids in future

Sphyraena arabiansis a new species of barracuda (Family: Sphyraenidae) from the south-west coast of India

A new species of barracuda Sphyraena arabiansis is described based on specimens collected from the eastern Arabian Sea off Kerala coast, India. The new species is morphologically similar to Sphyraena barracuda and both were so far considered as one species. Characters such as more and relatively small cycloid scales, 118-122 along lateral line, 11 along vertical axis above lateral line at first dorsal and 13 below the lateral line at anal origin; broad, round spoon shaped maxilla ending vertically below, before the anterior margin of the eye, narrow inter orbital area (4.2-5.13 in head length) and more prominent pointed paired central lobes of caudal fin make Sphyraena arabiansis sp. nov. clearly distinct from S. barracuda. Other distinguishing characters are prominent curve of the lateral line before the origin of first dorsal fin, absence of black spots on the body, white branchiostegal membrane, broad, thick and inwardly curved otoliths with round, blunt posterior end and an elongated, pointed anterior upper lobe. The mitochondrial Cytochrome oxidase C subunit 1 (COI) gene sequence studies revealed that the new species has distinct genetic divergence from S. barracuda and other species of the family occurring in the area

Proximate composition and fatty acid profile of the myctophid Diaphus watasei Jordan & Starks, 1904 from the Arabian Sea

The edible portion of Diaphus watasei, a benthopelagic fish collected off Quilon, south-west coast of India was analysed for proximate composition and fatty acid profile. The fleshy part of the fish was found to contain 15.62% protein, 11.71% fat, 0.47% minerals, 0.28% soluble carbohydrate and 0.01% crude fibre. The dry matter in the fish was found to be about 28%. Monounsaturated fatty acids (MUFA) were found to have the highest (36.7%) share among total fatty acids followed by saturated fatty acids (SFA) (33.3%) and polyunsaturated fatty acids (PUFA) (25.5%). The abundant fatty acids were found to be oleic acid, palmitic acid, docosahexaenoic acid, stearic acid, myristic acid, linolenic acid, eicosapentaenoic acid and palmitoleic acid. The most predominant fatty acid was recorded as oleic acid which contributed 32% to the total fatty acids. Docosahexaenoic acid formed the single largest component of PUFA (9.33%) followed by γ linolenic acid (3.97%) and eicosapentaenoic acid (3.83%). The ω-3 PUFA contributed about 70% of the total PUFAs. The most important ω-3 PUFAs were EPA and DHA that contributed 73% to the total ù -3 polyunsaturated fatty acids

Fifteen new records of Batoids (Elasmobranchii) from waters off Andaman and Nicobar Islands, India

Marine waters of Andaman and Nicobar Islands, India in the tropical Indian Ocean, is a poorly explored high faunal diverse region. The present study documents new records of batoids from the region, identified during the fishery and diversity monitoring surveys conducted during November 2016 to June 2019 at different fish landing centers of Andaman and Nicobar Islands. Fifteen elasmobranch species including 2 wedgefishes, 1 skate and 12 rays were identified and confirmed as new reports for the region. Results of this study indicate that the elasmobranch diversity, especially batoid diversity of Andaman and Nicobar Islands are poorly documented and future systematic surveys including that of deeper reef habitat may help to explore the diversity in the region

Fishery, biology and dynamics of dogtooth tuna, Gymnosarda unicolor (Rüppell, 1838) exploited from Indian seas

Dogtooth tuna, Gymnosarda unicolor (Rüppell, 1838) (Fig. 1) is a pelagic tuna preferring waters of temperature between 21 and 26 oC. It is one of the principal species exploited by hook and line (recreational as well as commercial fishery) operated in the oceanic region. Meat of dogtooth tuna is white and so it has great demand and fetch high price (IUCN, 2011). However, occasional ciguatera fish poisoning in humans has been reported on consumption of dogtooth tuna. It is exported in fresh and frozen state and is used for the production of sashimi, canned tuna, and pouch products. Most of the world landings of dogtooth tuna during 1963 -2006 was from the Indian Ocean. Small scale tuna long lines for the species operating in the Indian Ocean belong to Taiwan, Srilanka, Maldives, Japan or Pakista

Molecular identification of Bigeyes (Perciformes, Priacanthidae) from Indian waters

Thirty-five individuals of six priacanthid fish species were sampled from different localities along the coast of India covering the Arabian Sea and Bay of Bengal. The partial sequence of 16S rRNA and cytochrome oxidase subunit I (COI) genes were analyzed for species identification and phylogenetic relationship among the Indian priacanthids (Priacanthus hamrur, P. prolixus, P. blochii, P. sagittarius, Cookeolus japonicus, and Pristigenys refulgens). The intraspecies genetic distance ranged from 0.000 to 0.002, while distances varied from 0.008 to 0.157 interspecies based on 16S sequences. Using COI data analysis, the intraspecies genetic distance ranged from 0.000 to 0.005, while interspecies distances varied from 0.009 to 0.108. Several sequences labeled Priacanthus hamrur in GenBank are shown to be P. prolixus. We also observed cryptic speciation in Heteropriacanthus cruentatus. Partial sequences of 16S rRNA and COI genes provided phylogenetic information to distinguish thirteen species of priacanthids, indicating the usefulness of molecular markers in species identification

Seamount associated fishery of south-west coast of India - a preliminary assessment

West coast of India accounts for 55% of the total marine capture fishery production of India. Wider continental shelf with high productivity due to coastal upwelling is attributed to this large contribution. Present study shows that fishing in the seamounts, knolls, guyots and ridges in the Arabian Sea too contribute considerably to the landings of west coast. During 2010 and 2011, an estimated 2314 and 1934 t of fishes were landed from seamounts and associated knolls at Kochi (Kerala) in the west coast. Landings were supported mostly by commercially important high value large pelagics, elasmobranchs, carangids and perches. Present study indicates that these areas are under intensive exploitation and more detailed studies are needed for critical status assessment of resources in these vulnerable habitats

Arabian Sicklefin Chimaera Neoharriotta pumila

The Arabian Sicklefin Chimaera (Neoharriotta pumila) inhabits waters off Socotra, Yemen and Somalia at depths of 100–1,120 m. It may have a wider distribution in the Indian Ocean, particularly at depths of 1,000 m or more. The maximum size is around 65 cm total length, but biology is poorly-known. There are no targeted fisheries for the species and it is not known from bycatch given its deep occurrence. As there are currently no known threats to this species, it is therefore listed as Least Concern

Assessment of the fishery and stock of striped bonito, Sarda orientalis (Temminck and Schlegel, 1844) along Kerala coast with a general description of its fishery from Indian coast

The striped bonito Sarda orientalis (Temminck and Schlegel, 1844) has a wide distribution in the Indo- Pacific region from east coast of Africa to the west coast of America (Jones, 1960). It grows to a length of over half a metre and does not form a regular fishery of any appreciable magnitude anywhere

Report of silverstripe blassop, Lagocephalus sceleratus (Gmelin, 1789) (Tetraodontidae) from south-west coast of India

The silverstripe blassop, Lagocephalus sceleratus (Gmelin, 1789), is reported from the south-west coast of India (Kerala coast), which is characterised by a grey-brownish dorsal surface with black, regularly distributed spots of equal size and a wide silver band laterally on each side. The specimen collected is described and figured