Kv Akhilesh - Academia.edu (original) (raw)

Papers by Kv Akhilesh

Research paper thumbnail of Aspects of the biology of the pygmy ribbontail catshark Eridacnis radcliffei (Proscylliidae: Carcharhiniformes) from the south-west coast of India

Journal of fish biology, 2012

Biological data are presented for the pygmy ribbontail catshark Eridacnis radcliffei based on spe... more Biological data are presented for the pygmy ribbontail catshark Eridacnis radcliffei based on specimens collected from the by-catch of the commercial deep-sea shrimp trawl fishery operating in the Arabian Sea off the south-west coast of India. A total of 549 individuals, from 101 to 257 mm total length (LT) and 2·2 to 56 g, were collected. The LT at first maturity (LT50) of females and males was estimated at 183 and 170 mm, respectively, and analysis of stomach contents revealed that E. radcliffei feeds primarily on crustaceans.

Research paper thumbnail of Redescription of Chlorophthalmus corniger, a senior synonym of Chlorophthalmus bicornis (Family: Chlorophthalmidae

Journal of fish biology, 2014

Chlorophthalmus corniger is redescribed on the basis of recently collected specimens. The species... more Chlorophthalmus corniger is redescribed on the basis of recently collected specimens. The species is redefined as a species of Chlorophthalmus with the lower jaw terminating in a distinctly projecting horizontal plate with strong, spine-like processes directed forward from the plate's corners; body silvery grey, with numerous minute black spots and traces of broad darker crossbars; base of anterior dorsal fin spines and distal parts of dorsal fins black; adipose fin tiny with numerous black spots; caudal fin black; 3·5 scales above lateral line; three rows of cheek scales; head very large, 34·3–40·1% standard length (LS); eye large, 29·8–40·8% head length (LH); pectoral fin long, extending to beyond dorsal fin base, 21·7–26·2% LS. Chlorophthalmus bicornis is a junior synonym of C. corniger based on the examination of the type series of both species. It is confined to the northern half of the Indian Ocean, reliably recorded from Somalia and the Gulf of Aden to southern Java, Indonesia, at depths between 200 and 500 m. A lectotype and three paralectotypes were designated for C. corniger. DNA barcodes for Indian species of Chlorophthalmus were generated.

Research paper thumbnail of Plectranthias alcocki, a new anthiine fish species (Perciformes: Serranidae) from the Arabian Sea, off southwest India

Zootaxa, 2014

A new species of anthiine fish, Plectranthias alcocki n. sp. is described and illustrated based o... more A new species of anthiine fish, Plectranthias alcocki n. sp. is described and illustrated based on two specimens, (63.7-72.5 mm SL), recently collected from deep-waters of the Arabian Sea, off Kollam, Kerala, India. The following combination of characters distinguishes it from all other congeners: Dorsal-fin rays X, 15; anal-fin rays III, 7; pectoral-fin rays 14, all unbranched; pelvic-fin rays I, 5; lateral-line complete, the pored lateral-line scales 28; scales above lateral line to origin of dorsal fin 1; scales dorsally on head extending to posterior nostrils; no scales on maxilla or chin; gill rakers 5 + 11 (2 + 7 developed); circumpeduncular scales 10; fourth dorsal spine longest, 2.8 (2.6) in head length (HL), longest dorsal-fin soft ray (second) 2.4 (2.7) in head length; body depth 34.4 (35)% SL; head length 46 (49.8)% SL; orbital length 8.6 in SL; margin of preopercle finely serrate, the serrae 33 (28), ventral edge without antrorse spines; dorsal fin continuous and notched; first anal-fin spine 4.9 (5.6) in HL, second anal-fin spine 2.2 (2.6) in HL; pelvic fins relatively short, 4.0-4.3 in SL; the dorsal fin with a black blotch at base of fourth to eighth spines, one at base of the last three spines, and two at base of soft portion of fin, the dark pigment extending onto adjacent body.

Research paper thumbnail of Rediscovery of Lophiodes triradiatus (Lloyd, 1909), a senior synonym of L. infrabrunneus Smith and Radcliffe (Lophiiformes: Lophiidae

Zootaxa, 2014

Examination of the holotype and three recently collected additional specimens from the Indian Oce... more Examination of the holotype and three recently collected additional specimens from the Indian Ocean has revealed that Lophius triradiatus Lloyd, 1909 (now under Lophiodes) is a valid species and a senior synonym of Lophiodes infrabrunneus Smith & Radcliffe, 1912 and Lophiodes abdituspinus Ni, Wu & Li, 1990. A detailed description of the additional specimens is provided.

Research paper thumbnail of Publications

Research paper thumbnail of Catch composition, reproductive biology and diet of the bramble shark Echinorhinus brucus (Squaliformes: Echinorhinidae) from the south-eastern Arabian Sea

Journal of fish biology, 2013

Fishery and biological data are presented for the poorly known bramble shark Echinorhinus brucus ... more Fishery and biological data are presented for the poorly known bramble shark Echinorhinus brucus (Squaliformes: Echinorhinidae), from the deep waters of the south-eastern Arabian Sea. A total of 5318 individuals from by-catch landings of deep-water bottom set longlines, gillnets and shrimp trawl fisheries operating at depths of 200–1200 m were recorded between January 2008 and December 2011 at the Kochi Fisheries Harbour (Kerala). A total of 431 individuals, from 46 to 318 cm total length (LT) and 0·8 to 132 kg total mass (MT), were examined to determine biological data for this species. The LT at which 50% were mature (LT50) for females and males was estimated at 189 and 187 cm LT. Litter size ranged from 10 to 36 and size at birth was between 42 and 46 cm LT. Dietary analysis of stomach contents revealed E. brucus feeds on a variety of prey including crustaceans (69% index of relative importance, IRI), teleosts (25·8% IRI), cephalopods (1·7% IRI) and elasmobranchs (0·7% IRI). This study provides the first detailed biological data for this species and also highlights the extent of the by-catch fishery for this species in Indian waters.

Research paper thumbnail of Biological observations on the bristly catshark Bythaelurus hispidus from deep waters off the south-west coast of India

Journal of fish biology, 2013

Biological data are presented for the poorly known bristly catshark Bythaelurus hispidus based on... more Biological data are presented for the poorly known bristly catshark Bythaelurus hispidus based on specimens collected from the by-catch of the commercial deep-sea shrimp trawl fishery operating in the Arabian Sea at depths of 200–500 m off the south-west coast of India. One hundred and sixty-two individuals, which ranged from 120 to 366 mm total length (LT), were collected for this study. Size-at-maturity (L50) for females and males was estimated at 252 and 235 mm LT, respectively. The reproductive mode of B. hispidus was aplacental viviparity, which is the rarest reproductive mode within the Scyliorhinidae and is considered to be the most advanced of the three reproductive modes occurring within this family. Dietary analysis of stomach contents revealed B. hispidus feeds on a variety of prey, primarily fishes.

Research paper thumbnail of Aspects of the biology of the pygmy ribbontail catshark Eridacnis radcliffei (Proscylliidae: Carcharhiniformes) from the south-west coast of India

Journal of fish biology, 2012

Biological data are presented for the pygmy ribbontail catshark Eridacnis radcliffei based on spe... more Biological data are presented for the pygmy ribbontail catshark Eridacnis radcliffei based on specimens collected from the by-catch of the commercial deep-sea shrimp trawl fishery operating in the Arabian Sea off the south-west coast of India. A total of 549 individuals, from 101 to 257 mm total length (LT) and 2·2 to 56 g, were collected. The LT at first maturity (LT50) of females and males was estimated at 183 and 170 mm, respectively, and analysis of stomach contents revealed that E. radcliffei feeds primarily on crustaceans.

Research paper thumbnail of Redescription of Chlorophthalmus corniger, a senior synonym of Chlorophthalmus bicornis (Family: Chlorophthalmidae

Journal of fish biology, 2014

Chlorophthalmus corniger is redescribed on the basis of recently collected specimens. The species... more Chlorophthalmus corniger is redescribed on the basis of recently collected specimens. The species is redefined as a species of Chlorophthalmus with the lower jaw terminating in a distinctly projecting horizontal plate with strong, spine-like processes directed forward from the plate's corners; body silvery grey, with numerous minute black spots and traces of broad darker crossbars; base of anterior dorsal fin spines and distal parts of dorsal fins black; adipose fin tiny with numerous black spots; caudal fin black; 3·5 scales above lateral line; three rows of cheek scales; head very large, 34·3–40·1% standard length (LS); eye large, 29·8–40·8% head length (LH); pectoral fin long, extending to beyond dorsal fin base, 21·7–26·2% LS. Chlorophthalmus bicornis is a junior synonym of C. corniger based on the examination of the type series of both species. It is confined to the northern half of the Indian Ocean, reliably recorded from Somalia and the Gulf of Aden to southern Java, Indonesia, at depths between 200 and 500 m. A lectotype and three paralectotypes were designated for C. corniger. DNA barcodes for Indian species of Chlorophthalmus were generated.

Research paper thumbnail of Plectranthias alcocki, a new anthiine fish species (Perciformes: Serranidae) from the Arabian Sea, off southwest India

Zootaxa, 2014

A new species of anthiine fish, Plectranthias alcocki n. sp. is described and illustrated based o... more A new species of anthiine fish, Plectranthias alcocki n. sp. is described and illustrated based on two specimens, (63.7-72.5 mm SL), recently collected from deep-waters of the Arabian Sea, off Kollam, Kerala, India. The following combination of characters distinguishes it from all other congeners: Dorsal-fin rays X, 15; anal-fin rays III, 7; pectoral-fin rays 14, all unbranched; pelvic-fin rays I, 5; lateral-line complete, the pored lateral-line scales 28; scales above lateral line to origin of dorsal fin 1; scales dorsally on head extending to posterior nostrils; no scales on maxilla or chin; gill rakers 5 + 11 (2 + 7 developed); circumpeduncular scales 10; fourth dorsal spine longest, 2.8 (2.6) in head length (HL), longest dorsal-fin soft ray (second) 2.4 (2.7) in head length; body depth 34.4 (35)% SL; head length 46 (49.8)% SL; orbital length 8.6 in SL; margin of preopercle finely serrate, the serrae 33 (28), ventral edge without antrorse spines; dorsal fin continuous and notched; first anal-fin spine 4.9 (5.6) in HL, second anal-fin spine 2.2 (2.6) in HL; pelvic fins relatively short, 4.0-4.3 in SL; the dorsal fin with a black blotch at base of fourth to eighth spines, one at base of the last three spines, and two at base of soft portion of fin, the dark pigment extending onto adjacent body.

Research paper thumbnail of Rediscovery of Lophiodes triradiatus (Lloyd, 1909), a senior synonym of L. infrabrunneus Smith and Radcliffe (Lophiiformes: Lophiidae

Zootaxa, 2014

Examination of the holotype and three recently collected additional specimens from the Indian Oce... more Examination of the holotype and three recently collected additional specimens from the Indian Ocean has revealed that Lophius triradiatus Lloyd, 1909 (now under Lophiodes) is a valid species and a senior synonym of Lophiodes infrabrunneus Smith & Radcliffe, 1912 and Lophiodes abdituspinus Ni, Wu & Li, 1990. A detailed description of the additional specimens is provided.

Research paper thumbnail of Publications

Research paper thumbnail of Catch composition, reproductive biology and diet of the bramble shark Echinorhinus brucus (Squaliformes: Echinorhinidae) from the south-eastern Arabian Sea

Journal of fish biology, 2013

Fishery and biological data are presented for the poorly known bramble shark Echinorhinus brucus ... more Fishery and biological data are presented for the poorly known bramble shark Echinorhinus brucus (Squaliformes: Echinorhinidae), from the deep waters of the south-eastern Arabian Sea. A total of 5318 individuals from by-catch landings of deep-water bottom set longlines, gillnets and shrimp trawl fisheries operating at depths of 200–1200 m were recorded between January 2008 and December 2011 at the Kochi Fisheries Harbour (Kerala). A total of 431 individuals, from 46 to 318 cm total length (LT) and 0·8 to 132 kg total mass (MT), were examined to determine biological data for this species. The LT at which 50% were mature (LT50) for females and males was estimated at 189 and 187 cm LT. Litter size ranged from 10 to 36 and size at birth was between 42 and 46 cm LT. Dietary analysis of stomach contents revealed E. brucus feeds on a variety of prey including crustaceans (69% index of relative importance, IRI), teleosts (25·8% IRI), cephalopods (1·7% IRI) and elasmobranchs (0·7% IRI). This study provides the first detailed biological data for this species and also highlights the extent of the by-catch fishery for this species in Indian waters.

Research paper thumbnail of Biological observations on the bristly catshark Bythaelurus hispidus from deep waters off the south-west coast of India

Journal of fish biology, 2013

Biological data are presented for the poorly known bristly catshark Bythaelurus hispidus based on... more Biological data are presented for the poorly known bristly catshark Bythaelurus hispidus based on specimens collected from the by-catch of the commercial deep-sea shrimp trawl fishery operating in the Arabian Sea at depths of 200–500 m off the south-west coast of India. One hundred and sixty-two individuals, which ranged from 120 to 366 mm total length (LT), were collected for this study. Size-at-maturity (L50) for females and males was estimated at 252 and 235 mm LT, respectively. The reproductive mode of B. hispidus was aplacental viviparity, which is the rarest reproductive mode within the Scyliorhinidae and is considered to be the most advanced of the three reproductive modes occurring within this family. Dietary analysis of stomach contents revealed B. hispidus feeds on a variety of prey, primarily fishes.