Actinopteri (ray-finned fishes) > Eupercaria/misc
() > Lethrinidae
(Emperors or scavengers) > Monotaxinae
Etymology: Gymnocranius: Greek, gymnos = naked + Greek, kranion = skull (Ref. 45335). More on author: Ogilby.
Environment: milieu / climate zone / depth range / distribution range
Marine; reef-associated; non-migratory; depth range 8 - 40 m (Ref. 2295). Subtropical; 15°S - 25°S
Western Pacific: Australia (east coast of southern Queensland and the southern half of the Great Barrier Reef). The name bitorquatus has been applied to this species, particularly by Australian authors.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 40.0 cm TL male/unsexed; (Ref. 2295); common length : 35.0 cm TL male/unsexed; (Ref. 2295)
soft rays: 9 - 10. Inner surface of pectoral fin without scales. Overall color is silver or whitish, often light brown or olive on upper sides. Each scale on sides has a brown spot forming longitudinal rows. Fins are uniformly clear to slightly yellowish. Fresh specimen have scattered brown flecks on sides. A blackish bar that runs through the eye may also be evident.
Generally solitary over sand or rubble areas adjacent to reefs . Feeds mainly on benthic invertebrates. Sometimes has a distasteful iodine flavor; however, untainted fish are good to eat.
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Carpenter, K.E. and G.R. Allen, 1989. FAO Species Catalogue. Vol. 9. Emperor fishes and large-eye breams of the world (family Lethrinidae). An annotated and illustrated catalogue of lethrinid species known to date. FAO Fish. Synop. 125(9):118 p. Rome: FAO. (Ref. 2295)
IUCN Red List Status (Ref. 123251)
CITES (Ref. 123416)
Threat to humans
Fisheries: minor commercial
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates based on models
Preferred temperature (Ref. 115969
): 24.5 - 27, mean 26.1 °C (based on 58 cells).
Phylogenetic diversity index (Ref. 82805
= 0.5010 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.02138 (0.01067 - 0.04284), b=2.97 (2.80 - 3.14), in cm total length, based on LWR estimates for this species & (Sub)family-body (Ref. 93245
Trophic level (Ref. 69278
): 3.4 ±0.41 se; based on food items.
Generation time: 2.0 ( na - na) years. Estimated as median ln(3)/K based on 1 growth studies.
Resilience (Ref. 120179
): Medium, minimum population doubling time 1.4 - 4.4 years (K=0.56; tmax=13).
Vulnerability (Ref. 59153
): Low to moderate vulnerability (26 of 100) .