Elasmobranchii (sharks and rays) > Rajiformes
(Skates and rays) > Rajidae
Etymology: Leucoraja: Greek, leykos = white + Latin, raja = a fish, Raja sp. (Ref. 45335).
Environment: milieu / climate zone / depth range / distribution range
Marine; demersal; oceanodromous (Ref. 51243); depth range 0 - 120 m (Ref. 93252). Temperate; 51°N - 34°N, 79°W - 55°W (Ref. 55278)
Western Atlantic: Newfoundland Banks and southern Gulf of St. Lawrence in Canada to North Carolina, USA.
Length at first maturity / Size / Weight / Age
Maturity: Lm ?, range 73 - 76 cm
Max length : 110 cm TL male/unsexed; (Ref. 7251); max. reported age: 21 years (Ref. 52109)
Morphology | Morphometrics
Disk rounded, with many small dark spots on upper surface. Usually 1-4 ocelli on upper surface on each side of disk, each with a dark brownish center and pale edge. Young have long middorsal row of large spines on disk and tail. Upper jaw has 72 rows of teeth (Ref. 7251). Lower surface usually white but marked with irregular pale brownish blotches (Ref. 6902).
Prefer sandy and gravelly bottoms in shoal water in the north range; to at least 90 m in south (Ref. 7251). Benthic (Ref. 5951). Those caught at Cans, Nova Scotia in Canada were found to have eaten dollarfish, cunner, and squid. Mostly inactive during daylight hours, but active under dark conditions (Ref. 10807). Oviparous. Distinct pairing with embrace. Young may tend to follow large objects, such as their mother (Ref. 205). Eggs are oblong capsules with stiff pointed horns at the corners deposited in sandy or muddy flats (Ref. 205). Egg capsules are 5.5-9.9 cm long and 3.5-5.3 cm wide (Ref. 41249, 7135, 71301).
Electric organ discharge (EOD) activity seemed more frequent during dark periods (Ref. 10808). The individual EOD of this species is monophasic, head-negative, and lasts 217 ms (Ref. 10011). This species is used only for the manufacture of fish meal.
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Oviparous, paired eggs are laid. Embryos feed solely on yolk (Ref. 50449). Distinct pairing with embrace. Young may tend to follow large objects, such as their mother (Ref. 205).
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. 115185)
CITES (Ref. 115941)
Threat to humans
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates of some properties based on models
Preferred temperature (Ref. 115969
): 1.5 - 14.4, mean 7.9 (based on 130 cells).
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00269 (0.00144 - 0.00504), b=3.22 (3.06 - 3.38), in cm Total Length, based on LWR estimates for this species & (Sub)family-body (Ref. 93245
Trophic Level (Ref. 69278
): 4.4 ±0.5 se; Based on diet studies.
Resilience (Ref. 69278
): Very Low, minimum population doubling time more than 14 years (tmax=20.8; tm=11-12; Fec assumed to be <100).
Prior r = 0.16, 2 SD range = 0.04 - 0.65, log(r) = -1.83, SD log(r) = 0.71, Based on: 2 K, 2 tgen, 2 tmax, 1 Fec records
Vulnerability (Ref. 59153
): High vulnerability (56 of 100) .