Elasmobranchii (sharks and rays) > Rajiformes
(Skates and rays) > Rajidae
Etymology: Rajella: Latin, raja, -ae = a sting ray (Raja sp.) (Ref. 45335).
Environment: milieu / climate zone / depth range / distribution range
Marine; bathydemersal; depth range 600 - 2300 m (Ref. 117245), usually 1300 - 1400 m (Ref. 11284). Boreal; 73°N - 37°N, 75°W - 5°W (Ref. 119696)
North Atlantic and adjacent Arctic: ne USA to Rockall Trough (British Isles) (Ref. 114953).
Length at first maturity / Size / Weight / Age
Maturity: Lm ?, range 65 - 75 cm
Max length : 90.0 cm TL male/unsexed; (Ref. 4426)
Lower surface of the discus dark brown, darker in upper surface. Without definite markings, outer edges of pectoral and pelvic fins shading to darker (Ref. 6902).
Found on deeper continental slopes and probably abyssal plains, mainly deeper than 1,400 m (Ref. 3167). Oviparous (Ref. 50449). Eggs have horn-like projections on the shell (Ref. 205).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Oviparous (Ref. 3167). 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
): 3.4 - 6.6, mean 5.4 °C (based on 13 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
): 3.7 ±0.5 se; based on size and trophs of closest relatives
Resilience (Ref. 120179
): Low, minimum population doubling time 4.5 - 14 years (Fec assumed to be <100).
Vulnerability (Ref. 59153
): High vulnerability (56 of 100) .