Holocephali (chimaeras) > Chimaeriformes
(Chimaeras) > Chimaeridae
(Shortnose chimaeras or ratfishes)
Etymology: Hydrolagus: hydro-, combining form of hydor (Gr.), water; lagos (Gr.), hare, i.e., “water rabbit,” probably referring to three pairs of tooth plates, which tend to protrude from the mouth like a rabbit’s incisors. (See ETYFish); marmoratus: Latin for marbled, referring to marbled pattern of greyish brown reticulations on sides. (See ETYFish).
Environment: milieu / climate zone / depth range / distribution range
Marine; bathydemersal; depth range 548 - 995 m (Ref. 76967). Deep-water
Western Pacific: Australia.
Length at first maturity / Size / Weight / Age
Maturity: Lm ?, range 60 - ? cm
Max length : 80.1 cm TL male/unsexed; (Ref. 76967)
Morphology | Morphometrics
This chimaeroid fish has a ventral caudal fin that that is not indented at its origin to form a separate anal fin and is distinguished from its congeners by the following characters: color of body pale brown with prominent reticulations on sides, dorsal fin and spine whitish basally; the dorsal-fin spine is slightly shorter than or subequal in height of first dorsal fin, while the pelvic fins somewhat rectangular in shape (not broadly rounded); pelvic claspers of males are
mostly pale, divided for the distal 2/3 of their length (Ref. 76967).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Didier, D.A., 2008. Two new species of the genus Hydrolagus Gill (Holocephali: Chimaeridae) from Australia. In Last, P.R., White, W.T. & Pogonoski, J.J. (eds.): Descriptions of New Australian Chondrichthyans. CSIRO Marine and Atmospheric Research Paper no. 22. (Ref. 76967)
IUCN Red List Status (Ref. 126983)
Threat to humans
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Preferred temperature (Ref. 123201
): 5.1 - 8.6, mean 6.8 °C (based on 133 cells).
Phylogenetic diversity index (Ref. 82804
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00309 (0.00128 - 0.00745), b=3.10 (2.89 - 3.31), in cm total length, based on LWR estimates for this Subfamily-BS (Ref. 93245
Trophic level (Ref. 69278
): 3.9 ±0.6 se; based on size and trophs of closest relatives
Resilience (Ref. 120179
): Low, minimum population doubling time 4.5 - 14 years (Deepwater species with few large eggs.).
Fishing Vulnerability (Ref. 59153
): Moderate to high vulnerability (52 of 100).