Elasmobranchii (sharks and rays) > Rajiformes
(Skates and rays) > Rajidae
Etymology: Dipturus: Greek, di = two + Greek, pteryx = fin (Ref. 45335).
Environment: milieu / climate zone / depth range / distribution range
Marine; bathydemersal; depth range 163 - 1200 m (Ref. 11284), usually 450 - 600 m (Ref. 36731). Deep-water; 21°N - 37°S, 20°W - 27°E (Ref. 114953)
Eastern Central Atlantic to Southwest Indian Ocean: off Mauritania to South Africa (east to Cape Province) (Ref. 114953).
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 115 cm TL male/unsexed; (Ref. 114953)
Morphology | Morphometrics
an all-dark longnose skate with an elongated, acutely triangular snout, and a stout tail - shorter than body and with mid-section swollen sausage-shaped; disc with narrowly rounded outer corners and smooth underside except for small denticles on snout; no thorns on nape or along back (Ref. 5578). Dark brown with irregular dark blotches dorsally; rear end of disc and pelvic fins blackish; underside dark brown with black pores and scattered lighter blotches on disc, at base of pelvic fins, around vent, and on tail (Ref. 5578).
Occurs in deeper slope waters (Ref. 4426). Feeds on benthic fishes, shrimps and crabs (Ref. 27637, Ref. 114953). Oviparous (Ref. 50449). Eggs have horn-like projections on the shell (Ref. 205). Males reaches maturity at ca. 101 cm TL (Ref. 114953).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Oviparous, paired eggs are laid. Embryos feed solely on yolk (Ref. 50449).
McEachran, J.D. and K.A. Dunn, 1998. Phylogenetic analysis of skates, a morphologically conservative clade of elasmobranchs (Chondrichthyes: Rajidae). Copeia 1998(2):271-290. (Ref. 27314)
IUCN Red List Status (Ref. 123251)
CITES (Ref. 123416)
Threat to humans
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Preferred temperature (Ref. 115969
): 6.3 - 11.8, mean 7.3 °C (based on 17 cells).
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00309 (0.00145 - 0.00660), b=3.22 (3.04 - 3.40), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.8 ±0.66 se; based on food items.
Resilience (Ref. 120179
): Low, minimum population doubling time 4.5 - 14 years (Assuming fecundity<100).
Vulnerability (Ref. 59153
): High vulnerability (65 of 100) .