Actinopterygii (ray-finned fishes) > Perciformes
(Perch-likes) > Acanthuridae
(Surgeonfishes, tangs, unicornfishes) > Nasinae
Etymology: Naso: Latin, nasus = nose (Ref. 45335).
Environment / Climate / Range
Marine; reef-associated; depth range 1 - 180 m (Ref. 89972). Tropical; 26°C - 29°C (Ref. 27115), preferred 28°C (Ref. 107945); 35°N - 33°S
Indo-Pacific: Red Sea and East Africa (Ref. 3145) to the Hawaiian, Marquesas and Tuamoto islands, north to southern Japan, south to Lord Howe and Rapa islands. Presence in Somalia to be confirmed (Ref. 30573).
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 70.0 cm FL male/unsexed; (Ref. 9710); common length : 50.0 cm TL male/unsexed; (Ref. 3146)
soft rays: 27 - 30. This species is characterized by the following: body depth 1.8 (in subadults) - 2.6 (adults) in SL; presence of a tapering body horn in adults projecting anteriorly at level of eye but not extending in front of mouth (horn first as a bump on forehead at a length of about 12 cm); dorsal profile from snout to horn straight, angle of about 45°; 2 peduncular plates with well-developed forward-curving knife-like spines; emarginate caudal fin when young, truncate with filamentous lobes in adult; olivaceous with blue peduncular plates and spines; dorsal and anal fins yellowish with narrow blue stripes (Ref. 27362).
Inhabit channels, moats, lagoon and seaward reefs with strong surge (Ref. 48637). Benthopelagic (Ref. 58302). Typically occurring in small groups. Sometimes solitary (Ref. 90102).Juveniles in shallow protected bays and harbours (Ref. 48637). Mainly diurnal, feed on coarse leafy brown algae like Sargassum. Pair-spawning has been observed.
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Spawn in pairs (Ref. 240).
Myers, R.F., 1991. Micronesian reef fishes. Second Ed. Coral Graphics, Barrigada, Guam. 298 p. (Ref. 1602)
IUCN Red List Status (Ref. 109396)
CITES (Ref. 94142)
Threat to humans
Reports of ciguatera poisoning (Ref. 4795)
Fisheries: commercial; gamefish: yes; aquarium: commercial
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
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=0.02188 (0.01536 - 0.03116), b=2.94 (2.84 - 3.04), based on LWR estimates for this species (Ref. 93245
Trophic Level (Ref. 69278
): 2.2 ±0.11 se; Based on food items.
Resilience (Ref. 69278
): Low, minimum population doubling time 4.5 - 14 years (K=0.14).
Vulnerability (Ref. 59153
): Low to moderate vulnerability (32 of 100) .