Actinopterygii (ray-finned fishes) > Perciformes
(Perch-likes) > Acanthuridae
(Surgeonfishes, tangs, unicornfishes) > Nasinae
Etymology: Naso: Latin, nasus = nose (Ref. 45335); caesius: Naso caesius is in reference to its most common ground color which is bluish grey.. More on author: Randall.
Environment / Climate / Range
Marine; reef-associated; depth range 15 - 50 m (Ref. 90102). Tropical
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 45.6 cm SL male/unsexed; (Ref. 9944)
(total): 6 - 7;
soft rays: 28 - 31. Bluish grey to grey-brown, capable of displaying a colour pattern of vertically elongate blotches (lighter or darker than ground colour) on side and upper part of body. Opercular and preopercular margins not dark brown. Caudal fin uniform in colour. Gill rakers on lower limb of gill arches entirely pale. Edge of lower lip not white (Ref 9808).
Pacific Ocean: Northern Marianas, Marshall Islands, Hawaiian Islands, Pitcairn group, Society Islands (French Polynesia), Australia and New Caledonia.
Benthopelagic over coral and rock (Ref. 58302). Occurs singly or in aggregations along clear seaward and outer lagoon reefs and channels (Ref. 37816). Feeds in midwater on zooplankton (Ref. 90102).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Randall, J.E. and L.J. Bell, 1992. Naso caesius, a new acanthurid fish from the Central Pacific. Pac. Sci. 46(3):344-352. (Ref. 9944)
IUCN Red List Status (Ref. 96402)
CITES (Ref. 94142)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningFecundityEggsEgg development
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=0.02399 (0.01032 - 0.05579), b=2.95 (2.76 - 3.14), based on LWR estimates for this Genus-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 2.3 ±0.2 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
): Medium, minimum population doubling time 1.4 - 4.4 years (Preliminary K or Fecundity.).
Vulnerability (Ref. 59153
): Moderate to high vulnerability (45 of 100) .