أشلاق (القروش و الشفانين) (sharks and rays) >
Rajiformes (Skates and rays) >
Rajidae (Skates)
Etymology: Leucoraja: Greek, leykos = white + Latin, raja = a fish, Raja sp. (Ref. 45335).
More on authors: Müller & Henle.
البيئة: الوسط / المنطقة المناخية / نطاق العمق / نطاق التوزيع
البيئة
بحري القاع; نطاق العمق 12 - 900 m (Ref. 106604), usually 20 - 250 m (Ref. 11284). Subtropical; 63°N - 15°N, 18°W - 36°E
Eastern Atlantic: Kattegat (Ref. 3167) and North Sea, around Great Britain, Ireland and the Mediterranean to Morocco and Senegal.
الطول عند النضج الأول / الحجم / وزن / العمر
النضج: Lm 57.5, range 45 - 71.8 cm
Max length : 81.0 cm TL ذكر/ مختلط الجنس; (Ref. 106604); 68.0 cm TL (female); common length : 40.0 cm TL ذكر/ مختلط الجنس; (Ref. 3261)
الأشواك الظهرية (المجموع) : 0; شوكة شرجية: 0. Snout short; upper surface entirely spinulose, but centre of pectoral fins more or less bare in adults, underside smooth except for prickly front edges; generally 9-13 thorns in a complete row around inner margin of eye, and a large triangle of thorns on nape or shoulder region; two parallel rows of strong thorns on each side of midline along tail; upper surface ochre to light greyish-brown with a large roundish black eye-spot in middle of each pectoral fin, underside white (Ref. 3167)
Body shape (shape guide): other; Cross section: flattened.
Feed on all kinds of bottom animals (Ref. 3167). Maximum sizes of up to 106 cm, that are occasionally reported for specimens from the North Sea are probably erroneous (Ref. 131089). 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 5.0-7.0 cm long and 3.1-3.9 cm wide (Ref. 41250). Around 70-150 eggs are laid per individual annually (Ref. 41250).
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)
حالة القائمة الحمراء للاتحاد الدولي لحفظ الطبيعة والموارد الطبيعية (Ref. 130435: Version 2025-2 (Global))
استخدامات بشرية
مصائد: غير مهمة تجارياً; حوض مائي: احواض مائية عامة
أدوات
تقارير خاصة
تنزيل XML
مصادر علي الأنترنت
تقديرات تستند إلى النماذج
مؤشر التنوع الشُعبي الوراثي (مرجع 82804) |
PD50 = 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high]. |
|
Bayesian length-weight
|
a=0.00245 (0.00211 - 0.00285), b=3.22 (3.18 - 3.26), in cm total length, based on LWR estimates for this species (Ref. 93245). |
مستوى غذائي (مرجع 69278) |
4.2 ±0.3 se; based on diet studies. |
المرونه (مرجع 120179) |
منخفض, الحد الزمني الأدني لتضاعف عدد أفراد المجتمع 4.5-14 سنة (K=0.11-0.16; tm=8-9; tmax=28; Fec<100). |
|
Rate of population increase |
Prior r = 0.41, 95% CL = 0.27 - 0.61, Based on 1 full stock assessment. |
ضعف الصيد (Ref. 59153) |
Moderate to high vulnerability (48 of 100). 🛈 |
قابلية التأثر بالمناخ (Ref. 125649) |
Low to moderate vulnerability (35 of 100). 🛈 |
فئة السعر (Ref. 80766) |
Medium.
|
المغذيات (Ref. 124155) |
Calcium = 14 [2, 254] mg/100g; Iron = 0.805 [0.076, 9.895] mg/100g; Protein = 16.4 [14.4, 18.5] %; Omega3 = 0.488 [0.206, 1.165] g/100g; Selenium = 28.6 [5.5, 148.2] μg/100g; VitaminA = 8.99 [0.73, 103.53] μg/100g; Zinc = 0.415 [0.024, 4.858] mg/100g (wet weight); |