أشلاق (القروش و الشفانين) (sharks and rays) >
Rajiformes (Skates and rays) >
Rajidae (Skates)
Etymology: Rajella: Latin, raja, -ae = a sting ray (Raja sp.) (Ref. 45335).
البيئة: الوسط / المنطقة المناخية / نطاق العمق / نطاق التوزيع
البيئة
بحري قاعية المعيشة; نطاق العمق 150 - 2117 m (Ref. 5951), usually 250 - ? m (Ref. 117245). Deep-water; 4°C - 6°C (Ref. 117245); 78°N - 42°N, 70°W - 30°E (Ref. 114953)
North Atlantic Ocean and adjacent fringes of the Arctic Region. Reported from the western Atlantic on eastern Grand Banks and Flemish Cap (about 46°N), a few records on the slope off Strait of Belle Isle to Davis Strait; probably continuous along the slope off Labrador; restricted in southwestern part of Greenland; eastern Atlantic off to most of Iceland to Faroe Islands, possible occurrence in western Irminger Sea and south to northern Rockall Trough; common in the Norwegian Deep and Skagerrak and northward along the Norwegian coast and shelf; periodic records in the southwestern Barents Sea.
الطول عند النضج الأول / الحجم / وزن / العمر
النضج: Lm ?, range 97 - ? cm
Max length : 125 cm TL ذكر/ مختلط الجنس; (Ref. 119696); أعلا وزن تم نشرة: 11.2 kg (Ref. 40637)
وصف مختصر
مفاتيح التعريف | الوصف الخارجي | قياسات المظهر الخارجي
الأشواك الظهرية (المجموع) : 0; شوكة شرجية: 0. Snout moderately long, its tip pointed and somewhat protruding; upper surface predominantly smooth, only on head and front margins more or less prickly, tail entirely spinulose, underside smooth; up to 4 thorns in front of as well as behind eye, a continuous median row of 42-51 thorns from nape to first dorsal fin (Ref. 3167). Upper surface plain fawn color, slate grey or clay grey, lower surface white, with a grey longitudinal band along tail and grey blotch on either side of cloaca (Ref. 6902).
Body shape (shape guide): other; Cross section: flattened.
Occur in moderately deep water but mainly around 250 m in boreal and partly arctic latitudes (Ref. 3167). Maximum reported depth at 2,117 m (Ref. 117245). Benthic (Ref. 58426). Feed on all kinds of bottom animals (Ref. 3167), invertebrates and fishes (Ref. 114953). Males mature at ca. 90 cm TL and young hatch at ca. 15 cm TL (Ref. 119696). 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 10.7 cm long and 7.7 cm wide (Ref. 41251, 41301). It is not commercially important, and is possibly taken at low level by-catch in deep-water longline and trawl fisheries (Ref. 117245).
دورة الحياة وسلوك التزاوج
النضج | التكاثر | وضع البيض | بيض | الخصوبة | اليرقات
Oviparous (Ref. 3167). 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)
حالة القائمة الحمراء للاتحاد الدولي لحفظ الطبيعة والموارد الطبيعية (Ref. 130435: Version 2025-2 (Global))
استخدامات بشرية
مصائد: تجاري; لعبة سمكه: نعم
أدوات
تقارير خاصة
تنزيل XML
مصادر علي الأنترنت
تقديرات تستند إلى النماذج
درجة الحرارة المفضلة (مرجع
123201): 1 - 8, mean 5.2 °C (based on 216 cells).
مؤشر التنوع الشُعبي الوراثي (مرجع
82804): PD
50 = 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00302 (0.00141 - 0.00645), b=3.24 (3.07 - 3.41), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref.
93245).
مستوى غذائي (مرجع
69278): 3.8 ±0.45 se; based on food items.
المرونه (مرجع
120179): منخفض, الحد الزمني الأدني لتضاعف عدد أفراد المجتمع 4.5-14 سنة (Fec assumed to be <100).
ضعف الصيد (Ref.
59153): High to very high vulnerability (75 of 100).
🛈
قابلية التأثر بالمناخ (Ref.
125649): Moderate to high vulnerability (54 of 100).
🛈
المغذيات (Ref.
124155): Calcium = 3.33 [0.48, 63.71] mg/100g; Iron = 0.27 [0.03, 3.63] mg/100g; Protein = 15.3 [13.3, 17.4] %; Omega3 = 0.449 [0.186, 1.105] g/100g; Selenium = 21.2 [3.8, 98.1] μg/100g; VitaminA = 3.65 [0.27, 47.82] μg/100g; Zinc = 0.24 [0.02, 2.78] mg/100g (wet weight);