click for previous page ARIID Ariu 2 1983 (=ARIID Ari 2) (Fishing Areas 57/71) FAO SPECIES IDENTIFICATION SHEETS FAMILY: ARIIDAE FISHING AREA 51 (W. Indian Ocean) Arius maculatus (Thunberg, 1792) OTHER SCIENTIFIC NAMES STILL IN USE: Arius falcarius Richardson. 1844 Taehysurus maculatus (Thunberg, 1792) VERNACULAR NAMES: FAO : En - Spotted catfish Fr - Machoiron tacheté Sp - Bagre manchado NATIONAL: DISTINCTIVE CHARACTERS: Dorsal profile of head as a steep slope to first dorsal fin base; 3 pairs of barbels around mouth, the maxillary pair extending to pectoral fin base (but becoming shorter in older specimens); head shield rugose and granulated from middle of or near posterior margin of orbit to supraoccipital process; supraoccipital process longer than broad at base with a median keel, its hind end nearly straight; median longitudinal groove deep, long, reaching base of supra- occipital process; predorsal plate V-shaped; premaxillary band of teeth on upper jaw 4 to 6 times as long as broad, mandibulary band of teeth on lower jaw deeply curved and narrowly interrupted; palate teeth granular or molarlike. in a single large, fully elliptical or semioval patch on each side (size of patch may vary greatly with age, in juveniles the granular teeth are few and sparse, the patch small and far behind the jaws). First dorsal fin and pectoral fins each with a strong spine, first dorsal fin ray often produced into a long filament; total anal fin rays 19 to 22. Colour: dark brown above, sides grey and belly whitish with dorsal view of head dusky spots, the whole body with a bright sheen. All fins black tipped. pectoral and pelvic fins dusky above, adipose mainly blackish. An occasional tinge of yellow may also be seen over the fin bases. DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA: Arius arius: teeth on roof of mouth median maxillary forming an ovate, not fully formed patch longitudinal barbel short on each side. groove A. jella: anal fin rays 17 or 18 (19 to 22 in A. maculatus). A. tenuispinis: tooth patches ellip- tical, shoe-shaped, placed far back in buc- cal cavity; median longitudinal groove very long and deep running onto supra- occipital process. A. caelatus: teeth on roof of mouth villiform, in a single, roughly tri- angular patch on each side. A. platystomus A. subrostratus and A. sumatranus: teeth on roof of mouth in a small, oval patch on each side. Further- more, head depressed, snout duck-bill shaped in A. platystomus; maxillary bar- A. tenuispinis A. platystomus A. subrostratus bels very short, not extending beyond orbit in A. subrostratus. Other Arius species known to occur in India and/or Pakistan: have more than one (2 or 3) tooth patches on roof of mouth. Batrachocephalus mino: maxillary barbels absent. Osteogeneiosus militaris: only a pair of stiff, semiosseous maxillary barbels present. premaxillary tooth patch A. caelatus A. arius A. tenuipinnis A. sumatranus premaxillary and palate (roof of mouth) tooth patches A. maculatus SIZE: Maximum: 61 cm; common between 20 and 40 cm. GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR: Within the area, found off the west coast of India, Sri Lanka and Pakistan. Elsewhere, along the east coast of India, Bangladesh, Burma to the Indo-Australian archipelago (not occurring in the Philippines or Australia). Found in inshore waters and estuaries. Feeds on invertebrates and small fishes. PRESENT FISHING GROUNDS: Inshore waters and estuaries. CATCHES, FISHING GEAR AND FORMS OF UTILIZATION : Separate statistics are not reported for this species, Caught mainly with bagnets, dipnets, bamboo stake traps and with line gear. Marketed mostly fresh. ARIID Ariu 3 1983 (=ARIID Ari 3) (Fishing Areas 57/71) FAO SPECIES IDENTIFICATION SHEETS FAMILY: ARIIDAE FISHING AREA 51 (W. Indian Ocean) Arius sagor (Hamilton, 1822) OTHER SCIENTIFIC NAMES STILL IN USE : Tachysurus sagor (Hamilton, 1822) VERNACULAR NAMES: FAO : En - Sagor catfish Fr - Mâchoiron sagor Sp - Bagre sagor NATIONAL: DISTINCTIVE CHARACTERS: Dorsal profile of head somewhat convex just in front of first dorsal fin, but then straight to the rather short and rounded snout; 3 pairs of barbels around mouth, the maxillary pair extending to middle of pectoral fin; head shield strongly granulated and rugose nearly up to anterior margin of orbit, in both young and adults; supraoccipital process large, subcircular posteriorly, broader than long; median longitudinal groove shallow, reaching a little beyond posterior margin of eye; predorsal plate butterfly-shaped, distinctly large; premaxil- lary band of teeth in upper jaw 5 times as long as broad, mandibulary bano of teeth in lower jaw deeply curved and medially interrupted; palate teeth (on roof of mouth) villiform, in 2 patches, placed side by side at an angle, middle patches rounded, outer patches ovate, usually separated from each other, but middle patches may be confluent in some specimens. First dorsal and pectoral fins with a strong spine, predorsal plate tips of spines with a filamentous prolongation, total anal fin rays 17 butterfly-shaped to 19. Colour: dark brown above, sides grey and belly whitish with dusky spots, the whole body with a bright sheen; ail fins black tipped, dorsal view of head pectoral and pelvic fins dusky above, adipose fin mainly blackish; when fresh, narrow, vertical bands of spots on body may be present. DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA: The presence of a large, butterfly-shaped predorsal plate readily distinguishes this species from all other sea catfishes occurring in the area. SIZE: Maximum: 45 cm; common between 20 and 40 cm. GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR: Within the area, found along the west coast of India and Pakistan. Elsewhere, occurring along the east coast of India, Bangladesh. Burma, Thailand. Malaya, Singapore, Indo- Australian Archipelago (but not occurring in Papua New Guinea or Australia). Found along the coastline, mainly around estuaries. Feeds mainly on invertebrates and small fishes. PRESENT FISHING GROUNDS: Shore waters around estuaries and rivers subject to tidal influence. CATCHES, FISHING GEAR AND FORMS OF UTILIZATION: Separate statistics are not reported for this species. Caught mainly with bagnets, shore seines and hook and line. Marketed mostly fresh. ARIID Ariu 4 1983 (=ARIID Ari 4) (Fishing Areas 57/71) FAO SPECIES IDENTIFICATION SHEETS FAMILY: ARIIDAE FISHING AREA 51 (W. Indian Ocean) Arius thalassinus (Rüppell, 1837) OTHER SCIENTIFIC NAMES STILL IN USE: Arius serratus Day, 1877 Tachysurus serratus (Day, 1877) Tachysurus thalassinus (Rüppell, 1837) Netuma thalassinus (Rüppell, 1837) VERNACULAR NAMES: FAO : En - Giant catfish Fr - Mâchoiron titan Sp - Bagre titán NATIONAL: adult juvenile DISTINCTIVE CHARACTERS: premaxillary and palatine (roof of mouth) tooth patches Dorsal profile of head sharply rising from occiput to first dorsal fin base; snout of varying shape: in males acute, pointed, with upper jaw longer than lower and premaxillary band of teeth exposed, in females rounded, jaws more or less equal, premaxillary band of teeth not so prominently visible; 3 pairs of barbels around mouth, the maxillary pair nearly reaching pectoral fin base; head shield weakly granulated and rugose, a prominent preorbital conical protuberance tapering as a wide V posteriorly; supraoccipitai process about 1.5 times as long as broad, its hind end slightly emarginate; median longitudinal groove short, wide anteriorly, extending to level of hind edge of opercle, not reaching to base of supraoccipital process; predorsal plate sharply rounded or conical; premaxillary hand of teeth in upper jaw 8 times as long as broad, mandibuiary band of teeth in lower jaw deeply curved and medially interrupted; palate teeth (on roof of mouth) williform, in 3 patches on each side, forming a triangle, posterior patch longest, Patches usually fused (may be slightly separated in juveniles). First dorsal and pectoral fins Dorsal view of head each with a strong spine, outer pelvic fin rays sometimes thickened in females; total anal fin rays 15 to 18. Colour: males are dark-red-brown to bluish-grey above, densely pigmented below, the whole body with a bronze lustre; numerous narrow, parallel transverse viridescent crossbands of greenish colour may be occasionally seen in fresh specimens; distal part of dorsal adipose, anal and caudal fins, as well as upper surface of pectoral and pelvic fins, dark. Females are uniformly dark or grey. DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA: All other Arius species: have only 1 or 2 tooth patches on palate (roof of mouth). Batrachocephalus mino: maxillary barbels absent. Osteogeneiosus militaris: only a pair of stiff, semiosseous maxillary barbels present (no mental barbels). SIZE: Maximum: 185 cm; common between 25 and 70 cm. GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR: Within the area, found along the east coast of Africa (Mozambique channel and Tanzania), in the Red Sea, Gulf of Aden, Gulf of Oman, Pakistan, west coast of India and Sri Lanka. Elsewhere, from the east coast of India to Thailand, Singapore, China, the Philippines, Japan. North Australia, Queensland, Indonesia and Polynesia. A marine species often found in estuaries, but rarely entering freshwater. Feeds mainly on crabs, prawns, mantis shrimp (Squilla species) but also on fishes and molluscs. PRESENT FISHING GROUNDS: Coastal waters throughout the area, down to about 100 m depth. CATCHES, FISHING GEAR AND FORMS UTILIZATION: Separate statistics are not reported for this species. Caught mainly with