أشلاق (القروش و الشفانين) (sharks and rays) >
Rajiformes (Skates and rays) >
Rajidae (Skates)
Etymology: Raja: Latin, raja, -ae = a sting ray (Raja sp.) (Ref. 45335).
Eponymy: These species are named after the research vessel ‘Walther Herwig’, from which all the holotypes were caught. The vessel was named after Walther Herwig (1838–1912), who is regarded as the founder of German fisheries science. (Ref. 128868), visit book page.
Environment: milieu / climate zone / depth range / distribution range
البيئة
بحري القاع; نطاق العمق 55 - 102 m (Ref. 4426). Tropical; 17°N - 15°N
Eastern Central Atlantic: endemic around Cape Verde.
الحجم / وزن / العمر
Maturity: Lm ?  range ? - ? cm
Max length : 50.0 cm TL ذكر/ مختلط الجنس; (Ref. 4426)
Found in shelf waters (Ref. 4426). Oviparous (Ref. 50449). Eggs have horn-like projections on the shell (Ref. 205).
Life cycle and mating behavior
النضج | التكاثر | وضع البيض | بيض | الخصوبة | 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. 130435: Version 2024-2)
استخدامات بشرية
أدوات
تقارير خاصة
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مصادر علي الأنترنت
Estimates based on models
Preferred temperature (Ref.
123201): 13.6 - 15.6, mean 14.2 °C (based on 9 cells).
Phylogenetic diversity index (Ref.
82804): PD
50 = 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00263 (0.00118 - 0.00585), b=3.26 (3.09 - 3.43), in cm total length, based on LWR estimates for this Genus-body shape (Ref.
93245).
مستوى غذائي (Ref.
69278): 3.6 ±0.6 se; based on size and trophs of closest relatives
المرونه (Ref.
120179): منخفض, الحد الزمني الأدني لتضاعف عدد أفراد المجتمع 4.5-14 سنة (Fec assumed to be <100).
Fishing Vulnerability (Ref.
59153): Moderate vulnerability (40 of 100).