(W. Indian Ocean) Leiognathus Elongat
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click for previous page LEIOG Leiog 4 1983 FAO SPECIES IDENTIFICATION SHEETS FAMILY: LEIOGNATHIDAE FISHING AREA 51 (W. Indian Ocean) Leiognathus elongatus (Günther, 1874) OTHER SCIENTIFIC NAMES STILL IN USE: None VERNACULAR NAMES: FAO : En - Slender ponyfish Fr - Sapsap élégant Sp - Motambo elegante NATIONAL: DISTINCTIVE CHARACTERS: Body elongate and slender, moderately compressed, not deeper than head length, maximum depth contained more than 3 times in standard length. Mouth pointing downward when protracted. Top of head scaleless, but cheek and breast covered with small scales. Colour: body silvery; back with irregular green and dark marbling; horizontal yellow band at mid-height of spinous part of dorsal fin, most of margin of soft part orange; underside of pectoral fin base with minute, dark dots; anal fin between 2nd and 3rd spines yellow, as also margin of anterior part of fin; males have bluish longitudinal stripes on belly. DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA: Other Leiognathus species: body deeper its depth greater than head length. and contained less than 3 times in standard length; no scales on cheek. Secutor species: mouth pointing upward when pro- tracted. Gazza species: caniniform teeth present in jaws. Species of Gerreidae: large scales present on most of head, nuchal crest absent (present in Leiognathidae). L. lineolatus SIZE : Maximum: 12 cm; common to 8 cm. GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR: Along the east coast of Africa to about 10°N, and scales here L. elongatus off southwest India. Outside the area, it occurs in the Eastern Indian Ocean and the South China Sea, including Indonesia, Thailand, the Philippines and South, China, extending westward and northward to southern Japan. Inhabits shallow waters down to depth of 40 m; usually found in schools near the bottom. Feeds mainly on small crustaceans, polychaetes and algae. PRESENT FISHING GROUNDS: Secutor sp. Leiognathus elongatus Gazza sp. Inshore waters, locally abundant, but rather res- protracted mouth tricted in its occurrence. CATCHES, FISHING GEAR AND FORMS OF UTILIZATION: Separate statistics are not reported for this species. Caught mainly with bottom trawls. Marketed mostly dried salted along with other smaller fishes; also used for fishmeal. LEIOG Leiog 5 1983 FAO SPECIES IDENTIFICATION SHEETS FAMILY: LEIOGNATHIDAE FISHING AREA 51 (W. Indian Ocean) Leiognathus equulus (Forsskål, 1775) OTHER SCIENTIFIC NAMES STILL IN USE: none VERNACULAR NAMES: FAO: En - Common ponyfish Fr - Sapsap commun Sp - Motambo común NATIONAL : DISTINCTIVE CHARACTERS: Body deep and compressed with a strongly humped back; body depth contained 1.73 to 1.90 times in standard length. Mouth pointing downward when protracted. Head and breast scaleless. Colour: in adults, back greyish, belly silvery, and close-set faint bars on back and sides; a dark brown saddle on caudal peduncle; axil of pectoral fin grey, posterior margin of caudal fin lobes dusky except for lower lobe, margin of soft dorsal fin black; pectorals, pelvics and anal fin colourless to yellowish. In juveniles (5 to 7 cm total length) thin, closely arranged grey vertical lines descending from back to about rnidheight; membrane between anal fin spines conspicuously yellow; posterior margin of caudal fin lobes pale yellow and dusky; other fins hyaline. Snout dotted black. DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA: L. fasciatus Leiognathus fasciatus: second dorsal spine greatly elongated, bars on back and sides more conspicuous, fewer in number and more widely spaced. L. smithursti: both second dorsal and second anal spines greatly elongated; no long vertical bars on back or sides. L. splendens and L. jonesi: breast scaled; vertical lines on back and upper sides distinctly wavy; a distinct black blotch on anterior part of dorsal fin. Other Leiognathus species: back not strongly arched, dorsal and ventral profiles more or less equally curved; colour pattern different. Secutor species: mouth pointing upward when pro- tracted. Gazza species: caniniform teeth present in jaws. L. smithursti Species of Gerreidae: head scaly and nuchal crest absent (present in Leiognathidae). scales here Secutor sp. Leiognathus equulus Gazza sp. L. splendens protracted mouth SIZE: Maximum: at least 24 cm; common to 18 cm. GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR: Within the area, known to occur off the Réunion and Comores Islands, Seychelles, Mauritius. Madagascar, Zan- zibar, in the Red Sea, the "Gulf" and off the coasts of India and Sri Lanka. Inhabits shallow waters, down to depths of about 40 m; found both, at the surface and the bottom; also enters brackish waters; adults move in schools. Feeds mainly on polychaetes, small crustaceans and small fishes. PRESENT FISHING GROUNDS: Inshore waters, throughout the year, locally rather abundant. CATCHES, FISHING GEAR AND FORMS OF UTILIZATION: Separate statistics are not reported for this species. Caught mainly with trawls and drift nets. Marketed dried salted together with other pony- fishes. LEIOG Leiog 6 1983 FAO SPECIES IDENTIFICATION SHEETS FAMILY: LEIOGNATHIDAE FISHING AREA 51 (W. Indian Ocean) Leiognathus fasciatus (Lacepède, 1803) OTHER SCIENTIFIC NAMES STILL IN USE : None VERNACULAR NAMES: FAO : En - Striped ponyfish Fr - Sapsap rayé Sp - Motambo rayado NATIONAL: DISTINCTIVE CHARACTERS: Body compressed and deep, the back more strongly arched than anterior part of belly; body depth contained 1.67 to 1.97 times in standard length. Mouth pointing downward when protracted. Second dorsal fin spine distinctly elongated. Head and breast scaleless. Colour: body silvery, back less so than belly. About 11 widely spaced, dark vertical lines on back super- imposed by a few yellow blotches and fading gradually toward lower sides. Margin of soft dorsal fin grey; posterior margin of caudal fin lobes black; pectorals, pelvics and anal fin hyaline the latter yellow along margin; pectoral fin axils yellow, fin bases dotted black. L. smithursti DISTINGUISHING CHARACTERS SIMILAR SPECIES OCCURRING IN THE AREA: 2nd anal spine Leiognathus smithursti: second anal, as well as second dorsal fin spine distinctly elongated; no long vertical bars on back or sides. L. leuciscus: second dorsal spine also elongated but body more slender and back with grey, irregular vermi- culations; dorsal and ventral profiles of body more or less equally curved. L. equulus: also has vertical bars on sides of body but these more numerous. Other Leiognathus species: second dorsal fin spine not elongated. Secutor species: mouth pointing upward when pro- tracted. L. leuciscus Gazza species: caniniform teeth in jaws. Species of Gerreidae: head scaly; nuchal crest absent (present in Leiognathidae). Secutor sp. Leiognathus fasciatus Gazza sp. L. equulus protracted mouth SIZE: Maximum: 21 cm; common to 17 cm. GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR: Within the area, known to occur off the Seychelles, Mauritius, Comores Islands, Madagascar, Zanzibar, the Red Sea, Gulf of Aden, coasts of India and Sri Lanka. Elsewhere, in the Eastern Indian Ocean and Western Central Pacific, extending westward to Samoa, Fiji and Australia. Inhabits shallow waters to depths of about 40 m, occurs mainly in schools. Feeds chiefly on polychaetes, small crustaceans and small fishes. PRESENT FISHING GROUNDS: Inshore waters throughout its range. CATCHES, FISHING GEAR AND FORMS OF UTILIZATION: Separate statistics are not reported for this species. Caught mainly with bottom trawls and drift nets along with other species of Leiognathus. Marketed mostly dried salted together with other members of the family. LEIOG Leiog 8 1983 FAO SPECIES IDENTIFICATION SHEETS FAMILY: LEIOGNATHIDAE FISHING AREA 51 (W. Indian Ocean) Leiognathus leuciscus (Günther, 1860) OTHER SCIENTIFIC NAMES STILL IN USE : ? Equulites novaehollandiae Munro, 1967 VERNACULAR NAMES: FAO : En - Whipfin ponyfish Fr - Sapsap fil Sp - Motambo de hebra NATIONAL: DISTINCTIVE CHARACTERS: Body compressed and rather elongate, the dorsal and ventral profiles almost equally convex; body depth contained 2.31 to 2.68 times in standard length. Mouth pointing downward when pro- tracted. Second dorsal fin spine distinctly, and second anal fin spine slightly elongated. Head scaleless, but scales present on breast. Colour: belly silvery; back with irregular, partly semi-circular, greyish qreen vermiculations, a row of oval yellow blotches below lateral line. Membrane between dorsal fin spines yellow at mid-height, edge of soft part of dorsal fin also yellow, superimposed with light grey; anal fin of similar colour to dorsal; posterior margin of caudal fin yellowish. DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA: Leognathus fasciatus: body much deeper, vertical stripes on back. L. fasciatus L. smithursti: body much deeper; second anal fin spine also greatly elongated. Other Leiognathus species (especially L. lineolatus. L. berbis and L. bindus which have similar markings on back): no elongated dorsal fin spines. L. bindus is also much deeper-bodied. Secutor species: mouth pointing upward when pro- tracted. Gazza species: caniniform teeth present in jaws. Species of Gerreidae: head scaly and nuchal crest absent (present in Leiognathidae). L. smithursti Secutor sp. Leiognathus leucìscus Gazza sp. protracted mouth L. lineolatus SIZE Maximum: 12 cm; common to 10 cm. GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR Within the area, known to occur off Madagascar, Seychelles and along the coasts of India and Sri Lanka. Elsewhere, in the Eastern Indian Ocean, the South China Sea and Australia. Inhabits shallow waters down to depths of about 40 m, predominantly near the bottom; usually found in schools. Feeds mainly on small shrimps, other crustaceans and polychaetes. PRESENT FISHING GROUNDS: Inshore waters, throughout the year. CATHES, FISHING GEAR AND FORMS OF UTILIZATION: Separate statistics are not reported for this species. Caught mainly with bottom trawls; also in bag nets and shore seines. Marketed fresh and dried salted, together with other ponyfishes; also used for fishmeal. click for next page.