Actinopteri (ray-finned fishes) > Ophidiiformes
(Cusk eels) > Carapidae
(Pearlfishes) > Carapinae
Etymology: Onuxodon: Greek, onyx, -ychos = nail + Greek, odous = teeth (Ref. 45335).
Environment: milieu / climate zone / depth range / distribution range
Marine; reef-associated. Tropical; 28°N - 23°S
Eastern Indian Ocean: restricted to western Australia.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 10.0 cm TL male/unsexed; (Ref. 1602)
Morphology | Morphometrics
Eel-like, shallow to moderate body depth; adults small, less than 100 mm, trunk compressed; 1 to several large symphyseal fangs on premaxilla and dentary; anterior swim bladder modified into 'rockerbone'; predorsal bone present; pectoral fin rays supported by numerous small distal radials (Ref. 34024). Precaudal vertebrae 18-20; relatively short and deep bodied (Ref. 34024).
Uncommon species (Ref. 34024) inhabiting coastal waters. Found in the mantle cavity of pearl oysters (Pinctada spp.) and other large bivalves (Ref. 1602) as well as in holothurians (Ref. 7300). It feeds on crustaceans and polychaetes and is reported to tend towards sexual pairing in the host (Ref. 1602).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Nielsen, J.G., D.M. Cohen, D.F. Markle and C.R. Robins, 1999. Ophidiiform fishes of the world (Order Ophidiiformes). An annotated and illustrated catalogue of pearlfishes, cusk-eels, brotulas and other ophidiiform fishes known to date. FAO Fish. Synop. 125(18):178p. Rome: FAO. (Ref. 34024)
IUCN Red List Status (Ref. 125652)
Threat to humans
Fisheries: of no interest
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82805
= 0.6250 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00102 (0.00046 - 0.00225), b=3.06 (2.88 - 3.24), in cm total length, based on all LWR estimates for this body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.3 ±0.41 se; based on food items.
Fishing Vulnerability (Ref. 59153
): Low vulnerability (10 of 100) .
Climate Vulnerability (Ref. 125649
): (0 of 100) .