أشلاق (القروش و الشفانين) (sharks and rays) >
Rajiformes (Skates and rays) >
Arhynchobatidae (Softnose skates)
Etymology: Bathyraja: Greek, bathys = deep + Latin, raja, -ae = a ray (Raja sp) (Ref. 45335).
More on authors: Müller & Henle.
Environment: milieu / climate zone / depth range / distribution range
البيئة
بحري قاعية المعيشة; نطاق العمق 440 - 1020 m (Ref. 5578). Deep-water; - 40°S
Southeast Atlantic: off central Namibia to Agulhas Bank, South Africa.
الحجم / وزن / العمر
Maturity: Lm ? range ? - ? cm
Max length : 120 cm TL ذكر/ مختلط الجنس; (Ref. 5578)
وصف مختصر
مفاتيح التعريف | الوصف الخارجي | قياسات المظهر الخارجي
A large softnose skate with a broadly triangular, bluntly pointed snout and an angular pectoral disc; tail shorter than body and with a single row of large thorns; upper disc of young with thorns but these are lost with growth (Ref. 5578). Dorsal surface greyish and may have white spots, ventral surface white with dark grey blotches around gill slits, vent and along ventral surface of tail (Ref. 5578). Tail with no color bands (Ref. 5578).
Found on the upper continental slope (Ref. 27121). A bottom-predator that feeds on bony fishes including hake, jacopever, barracudina and dragonet; also squid, octopus, crabs and prawns (Ref. 5578). Oviparous (Ref. 50449). Eggs have horn-like projections on the shell (Ref. 205). Sometimes caught by hake trawlers (Ref. 5578).
Life cycle and mating behavior
Maturities | التكاثر | Spawnings | Egg(s) | Fecundities | Larvae
Oviparous, paired eggs are laid. Embryos feed solely on yolk (Ref. 50449). Eggs have horn-like projections on the shell (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. 130435)
استخدامات بشرية
أدوات
تقارير خاصة
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مصادر علي الأنترنت
Estimates based on models
Preferred temperature (Ref.
123201): 4.6 - 11.8, mean 5.4 °C (based on 13 cells).
Phylogenetic diversity index (Ref.
82804): PD
50 = 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00513 (0.00253 - 0.01042), b=3.12 (2.95 - 3.29), in cm total length, based on LWR estimates for this Genus-body shape (Ref.
93245).
مستوى غذائي (Ref.
69278): 4.3 ±0.67 se; based on food items.
المرونه (Ref.
120179): منخفض, الحد الزمني الأدني لتضاعف عدد أفراد المجتمع 4.5-14 سنة (Fec assumed to be <100).
Fishing Vulnerability (Ref.
59153): High to very high vulnerability (72 of 100).
