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Naso unicornis (Forsskål, 1775)

Bluespine unicornfish
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Native range | All suitable habitat | Point map | Year 2100
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Naso unicornis   AquaMaps   Data sources: GBIF OBIS
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Philippines country information

Common names: Bagis, Bagis, Bagitan
Occurrence: native
Salinity: marine
Abundance: | Ref:
Importance: commercial | Ref:
Aquaculture: | Ref:
Regulations: | Ref:
Uses: no uses
Comments: Known from Nasugbu (Ref. 107853), Lanuza Bay (Ref. 104756), Puerto Princesa, Palawan (Ref. 58652), Bongo Island and Paril-Sangay Protected Seascape, Moro Gulf (Ref. 106380). Recorded from (San Luis, Bauan, Mabini, Lobo, San Juan) Batangas, between 3-7 m deep from Feb. - April 2014 (Ref. 107629). Also Ref. 1602, 37792, 48613, 53416, 121724.
National Checklist:
Country Information:
National Fisheries Authority:
Occurrences: Occurrences Point map
Main Ref: Rau, N. and A. Rau, 1980
National Database:

Common names from other countries

Classification / Names Common names | Synonyms | Catalog of Fishes(genus, species) | ITIS | CoL | WoRMS | Cloffa

Teleostei (teleosts) > Acanthuriformes (Surgeonfishes) > Acanthuridae (Surgeonfishes, tangs, unicornfishes) > Nasinae
Etymology: Naso: Latin, nasus = nose (Ref. 45335).
  More on author: Forsskål.

Environment: milieu / climate zone / depth range / distribution range Ecology

Marine; reef-associated; depth range 0 - 180 m (Ref. 89972).   Tropical; 26°C - 29°C (Ref. 27115); 35°N - 33°S, 30°E - 128°W

Distribution Countries | FAO areas | Ecosystems | Occurrences | Point map | Introductions | Faunafri

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); max. reported age: 55 years (Ref. 118238)

Short description Morphology | Morphometrics

Dorsal spines (total): 6; Dorsal soft rays (total): 27-30; Anal spines: 2; Anal soft rays: 27 - 30. This species is characterized by the following: body depth vary from about 2.0 in SL (in subadults) to 2.4-2.6 (adults) in SL; with a tapering, bony, horn on forehead of 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; males apparently with longer horn, larger peduncular keels and longer caudal filaments than females of the same size; body yellowish to olivaceous gray dorsally, paler ventrally, with blue peduncular plates and keel spines; lips whitish or blue; blue area is sometimes present around pectoral fin; dorsal and anal fins yellowish with narrow blue margins; caudal fin orangish basally, shading to gray, with a broad, pale greenish posterior border and caudal filaments are edged in blue; one transient color phase is a blotchy pale greenish zone below the spinous portion of dorsal fin that narrows and ends beneath the pectoral fin (Ref. 27362).

Biology     Glossary (e.g. epibenthic)

Adults 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. Minimum depth reported taken from Ref. 128797.

Life cycle and mating behavior Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae

Spawn in pairs (Ref. 240).

Main reference Upload your references | References | Coordinator : Randall, John E. | Collaborators

Myers, R.F., 1991. Micronesian reef fishes. Second Ed. Coral Graphics, Barrigada, Guam. 298 p. (Ref. 1602)

IUCN Red List Status (Ref. 123251)

  Least Concern (LC) ; Date assessed: 07 May 2010

CITES (Ref. 128078)

Not Evaluated

CMS (Ref. 116361)

Not Evaluated

Threat to humans

  Reports of ciguatera poisoning (Ref. 4795)

Human uses

Fisheries: commercial; gamefish: yes; aquarium: commercial
FAO(Fisheries: production; publication : search) | FishSource | Sea Around Us

More information

FAO areas
Food items
Food consumption
Common names
Egg development
Aquaculture profile
Allele frequencies
Mass conversion
Stamps, Coins Misc.
Swim. type
Gill area


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Internet sources

Estimates based on models

Preferred temperature (Ref. 115969): 23.4 - 28.8, mean 27.4 (based on 1536 cells).
Phylogenetic diversity index (Ref. 82804):  PD50 = 0.5000   [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.02344 (0.01735 - 0.03168), b=2.95 (2.86 - 3.04), in cm Total Length, based on LWR estimates for this species (Ref. 93245).
Trophic level (Ref. 69278):  2.2   ±0.11 se; based on food items.
Resilience (Ref. 120179):  Low, minimum population doubling time 4.5 - 14 years (K=0.14).
Prior r = 0.28, 95% CL = 0.16 - 0.49, Based on 3 stock assessments.
Fishing Vulnerability (Ref. 59153):  Low to moderate vulnerability (32 of 100).
Climate Vulnerability (Ref. 125649):  Very high vulnerability (80 of 100).
Price category (Ref. 80766):   Medium.