Actinopterygii (ray-finned fishes) > Perciformes
(Perch-likes) > Siganidae
Etymology: Siganus: Latin, siganus = a fish, rabbit fish; by the similarity of the nose (Ref. 45335).
Environment / Climate / Range
Marine; brackish; reef-associated; oceanodromous (Ref. 51243); depth range 3 - 50 m (Ref. 9813). Tropical; 30°N - 35°S
Length at first maturity / Size / Weight / Age
Maturity: Lm ?, range 18 - ? cm
Max length : 30.0 cm TL male/unsexed; (Ref. 11441); common length : 20.0 cm TL male/unsexed; (Ref. 9813)
soft rays: 9;
Vertebrae: 23. Body silvery gray above, silvery below; a touch of olive green on nape and upper surface of head; fright pattern mottled with pale cream and dark brown; usually fish display a dark patch just below origin of lateral line. Preopercular angle 89°-96°; cheeks appear to be scaleless but sometimes with few to many, fine, embedded scales on lower 2/3; midline of thorax scaleless between pelvic ridges. Margin of anterior nostril encircled by a low flange with the flap extending towards posterior flap; flap shortens with increasing size. Closely resembles S. fuscescens but differs by its slightly more pointed snout and longer pectoral fins (1.1-1.3 in HL vs. 1.4-1.5 in S. fuscescens) (Ref. 1602). Color pattern is similar to that of S. argenteus and S. fuscescens.
Indo-West Pacific: Persian Gulf, Gulf of Oman, Pakistan, India, Sri Lanka, Burma, Thailand, Singapore, Malaysia, Indonesia, Papua New Guinea, Philippines, Cambodia, Viet Nam, south China, Taiwan and Western Australia. Also known from Ryukyu Islands; Palau and Yap in Micronesia (Ref. 1602) and Melanesia (Ref. 712).
Inhabit inshore, algae reefs, estuaries and in large lagoons with algae-rubble habitats. Mainly common on rocky substrates (Ref. 48637). In contrast to S. fuscescens, this species seems to tolerate more turbid waters, occurring within the vicinity of river mouths especially around seagrass beds. Adults also occur several kilometers offshore in deep, clear waters. Juveniles form very large schools in shallow bays and coral reef flats; school size reduces with size, with adults occurring in groups of 20 individuals or so. Herbivorous, feed on benthic algae and to some extent on seagrass. Consumed as food; and have poisonous spines (Ref. 4537).
Woodland, D.J., 1990. Revision of the fish family Siganidae with descriptions of two new species and comments on distribution and biology. Indo-Pac. Fish. (19):136 p. (Ref. 1419)
IUCN Red List Status (Ref. 96402)
CITES (Ref. 94142)
Fisheries: commercial; aquaculture: commercial
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01148 (0.00656 - 0.02009), b=2.99 (2.84 - 3.14), based on LWR estimates for species & Genus-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 2.8 ±0.31 se; Based on food items.
Resilience (Ref. 69278
): High, minimum population doubling time less than 15 months (K=1.5-2.0; tm=1).
Vulnerability (Ref. 59153
): Low vulnerability (15 of 100) .