FAO SPECIES IDENTIFICATION SHEETS. FAMILY: LETHRINIDAE FISHING AREA 51 (W. Indian Ocean) Lethrinus conchyliatus (Smith, 1959)

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1 click for previous page LETH Leth FAO SPECIES IDENTIFICATION SHEETS FAMILY: LETHRINIDAE FISHING AREA 51 (W. Indian Ocean) Lethrinus conchyliatus (Smith, 1959) OTHER SCIENTIFIC NAMES STILE IN USE: Lethrinella conchyliata Smith, 1959 Lethrinus floridus Wheeler, 1961 VERNACULAR NAMES: FAO : En - Red axil emperor Fr - Empereur gueule de vin Sp - Emperador boca de vino NATIONAL: DISTINCTIVE CHARACTERS : Body depth less than head length. Interorbital space convex; eye laced well below the dorsal profile; snout long ario thin, usually with a distinct hump before eye; posterior nostril situated about midway between snout tip and hind margin of head; end of maxilla falling a little short of, or just reaching to vertical from anterior nostril; interorbital space prominently convex; lips flesh, not following profile of snout but instead curving outward from snout; posterclateral teeth ire jaws conical, never molariform; anterior teeth caniniform. Third or 4th dorsal fin spine longest. Five scale rows between dorsal profile (at 6th spine) and lateral line; inner surface of pectoral fin base unsealed. Colour: brown-blue-grey. Distinctive red marks on edge of opercle and on pectoral fin base; a subtriangular area above the basal part of pectoral fin conspicuously bright mauve/red. Fins yellowish-red. Lips red. DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA: Lethrinus xanthochilus: lips bright yellow; interorbital space flat; eye almost on dorsal profile.

2 L. rubrioperculatus: no red colour above pectoral fin base; eye amost on dorsal profile. L. semicinctus, L. variegatus, L. microdon and L. elongatus: no red colour on opercle or pectoral fin. Furthermore, hind nostril nearer to anterior one than to anterior margin of eye in L. variegatus; characteristic bluish lines from eye across snout and opercle in L. microdon; snout longer, eye smaller and a conspicuous red line above and below the lips in L. elongatus; a large dark blotch on sides in L. semicinctus. Other Lethrinus species: snout not as elongate; body depth greater than head length in large adults (sometimes equal or a little less in young); posterolateral dentition includes molariform or at least rounded teaeth in adults; inner surface of pectoral fin base densely scaled, except in L. lentjan. L. rubrioperculatus L. semicinctus L. elongatus SIZE Maximum: L. variegatus 76 cm; common to 50 cm. L. microdon GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR: Within the area, reported from the east African coast between 0 and about 20 S, Seychelles, Maldives, Chagos Archipelago, and western and southern coasts of India. Elsewhere, it occurs in the Andaman Sea. Inhabits deeper coastal waters in the continental shelf, but is also reported from waters near coral reefs to 220 m depth. Feeds on crustaceans and small fishes. PRESENT FISHING GROUNDS: Coastal areas and a deeper coral reef waters down to 220 m depth. CATCHES, FISHING GEAR AND FORMS OF UTILIZATION: Separate statistics are not reported for this species. Caught mainly with handlines, bottom trawls, gillnets and traps. Marketed mostly fresh.

3 LETH Leth FAO SPECIES IDENTIFICATION SHEETS FAMILY: LETHRINIDAE FISHING AREA 51 (W. Indian Ocean) Lethrinus crocineus Smith, 1959 OTHER SCIENTIFIC NAMES STILL IN USE: None VERNACULAR NAMES: FAO : NATIONAL: En - Yellowtail emperor Fr - Empereur à queue jaune Sp - Emperador rabo amarillo DISTINCTIVE CHARACTERS: Body depth greater than head length, the greatest depth at pectoral fin base. Interorbital space slightly convex; snout blunt, forming an angle of about 70 with the maxilla and about 90 with a line drawn from the pectoral fin base through centre of eye; hind tip of maxilla nearly reaching a vertical through posterior nostril, its length greater than least depth of caudal peduncle, 2.4 to 2.7 times in head; distance between anterior and posterior nostrils 15 or 16 times in head; posterolateral teeth in jaws include distinct molars in adults; anterior teeth caniform. Fourth dorsal fin spine longest. Five scale rows between lateral line and median dorsal fin spines (excluding very small scales at base of dorsal fin); inner surface of pectoral fin base finely scaled. Colour: brownish yellow dorsally, shading 'o white ventrally, with a black sot at base of each scale above lateral line; most scales on side of body with a vertically elongate blackish spot (on ventral part of body scale markings weak or absent); some individuals show faint pale bluish bars on body; unscaled part of head yellowish brown, the unscaled nape region darker; caudal in yellow, the upper and lower edges pale bluish; distal edge of dorsal fin yellow-orange; pectoral fins with pale orange-yellow rays, clear membranes, and a dark bluish spot at upper base.

4 DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA: Lethrinus mahsena: 4 rows of scales above lateral line to base of middle dorsal rays (excluding very small scales at base of pectoral fin); upper edge of pectoral fin with a submarginal red streak. L. mahsenoides: 6 rows of scales above lateral line to base of middle dorsal rays. L. nebulosus: usually 2 or 3 blue stripes on head; hind tip of maxilla not reaching beyond anterior nostril; interorbital space well convex; 6 scale rows between lateral line and median dorsal fin spines. L. ramak: conspicuous yellow-orange stripes present on body; body not as deep, 2.4 to 3 times in standard length (2.3 to 2.8 times in L. mahsena); hind tip of maxilla not extending beyond vertical from anterior nostril. L. harak: a conspicuous dark blotch on sides of body. L. elongatus, L. microdon and L. variegatus: body more slender, its depth less than head length; no molars among posterolateral teeth; inner surface of pectoral fin base scaleless. Furthermore, distinctive colour patterns in L. elongatus and L. microdon. L. ramak Other Lethrinus species: conspicuous red colour on opercle, other parts of head or pectoral fin base. L. harak L. elongatus L. microdon SIZE: Maximum: 45 cm. GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR: Known only from the East African coast from Pinda, Mozambique to southern Natal. Because this species has been confused with L. mahsena, its exact distribution is not known. Reported as often taken in water to about 150 m. PRESENT FISHING GROUNDS: Caught incidentally throughout its range. CATCHES, FISHING GEAR AND FORMS OF UTILIZATION: Separate statistics are not reported for this species. Caught mainly with handlines. Marketed mostly fresh. L. variegatus L. nebulosus

5 LETH Leth FAO SPECIES IDENTIFICATION SHEETS FAMILY: LETHRINIDAE FISHING AREA 51 (W. Indian Ocean) Lethrinus hypselopterus Bleaker, 1873 OTHER SCIENTIFIC NAMES STILL IN USE: None VERNACULAR NAMES: FAO : En - fvlozambique emperor Fr - Empereur békine Sp - Emperador mozambiqueño NATIUNAL DISTINCTIVE CHARACTERS: Body depth greather than head length. Interorbital space flat or a little convex; hind tip of maxilla reaching to vertical from posterior nostril; lateral teeth in jaws include strong molars in adults; anterior teeth caniniform. Fourth to 6th dorsal fin spines longest; soft part of anal fin base distinctly shorter than longest anal ray. Five scale rows between lateral line and median dorsal fin spines; inner surface of pectoral fin base scaled. Colour: yellowish-brown, paler below; a red stripe from eve to tip of snout; a red line backward from corner of mouth; a red spot on upper half of pectoral fin tease; posterior rim of opercle red; fins uniformly red.

6 DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA: Lethrinus kaliopterus: has a caudal fin with lobes conspicuously obtuse; lateral dentition of jaws include wide and roundish teeth but not distinct molars; distinctive orange spots on sides of head. L. mahsena: lips red, but no red colour on opercle or pectoral fin base; soft anal fin base longer than longest dorsal soft ray. Other Lethrinus species: either 6 scale rows between lateral line and median dorsal fin spines (5 in L. hypselopterus), or body depth smaller than head length. Furthermore, most species have different colour patterns. L. kaliopterus SIZE: Maximum: 50 cm, common to 30 cm. GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR: Within the area, reported only from Mozambique. Elsewhere, in the Eastern Indian Ocean and Western Central Pacific, to Philippines and Solomon Islands. L. mahsena Inhabits coastal waters. Feeds mainly on benthic invertebrates and small fishes. PRESENT FISHING GROUNDS: Coastal waters throughout its range. CATCHES, FISHING GEAR AND FORMS OF UTILIZATION: Separate statistics are not reported for this species. Caught mainly with handlines, gillnets and traps. Marketed mostly fresh, click for next page