Ελασμοβράγχιοι (καρχαρίες και σαλάχια) (sharks and rays) >
Rajiformes (Skates and rays) >
Rajidae (Skates)
Etymology: Rostroraja: Latin, rostrum = beak + Latin, raja, -ae = a sting ray (Ref. 45335).
Περιβάλλον: περιβάλλον / κλιματική ζώνη / εύρος βάθους / εύρος διανομής
Οικολογία
Θαλασσινό(ά); Υφάλμυρο βενθικό(ς); ωκεανόδρομο(ς) (Ref. 51243); εύρος βάθους 0 - 330 m (Ref. 92298), usually 0 - 50 m (Ref. 55280). Subtropical; 48°N - 22°N, 91°W - 59°W (Ref. 55280)
Western Atlantic: Massachusetts to southern Florida (USA) and eastern Gulf of Mexico. Also northern Gulf of Mexico (Ref. 26938).
Μήκος κατά την πρώτη ωρίμανση / Μέγεθος / Βάρος / Ηλικία
Γεννητική Ωρίμανση: Lm 53.5, range 49 - 60 cm
Max length : 84.0 cm TL αρσενικό/απροσδιόριστο; (Ref. 1125)
Small skate, with irregular darker spots and bars on dorsal surface. Translucent area on each side of mid-dorsal ridge on snout (Ref. 26938). Single row of thorns along the midridge of the back (Ref. 6902). Disk with dark brown bars and streaks and some spots. Front edges nearly straight or slightly concave (Ref. 7251).
Body shape (shape guide): other.
Found from saltwater parts of estuaries and bays of 330 m (Ref. 26938). Inhabit inshore areas. Prefer waters of 10°-21°C. Feed mainly on decapod crustaceans, bivalves, polychaetes, squids and fishes (Ref. 3824). Breed while inshore (Ref. 6902). 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 5.1-8.9 cm long and 3.8-5.7 cm wide (Ref. 41249, 41307, 41301, 41358).
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).
From the work of Libby and Gilbert (1960) (Ref. 51117) and Luer and Gilbert (1985) (Ref. 38742) male and female clearnose skates mate side by side in an upright position (Ref. 49562). Actual copulation occurs when the male bites the caudal margin of the female's pectoral, bends his tail 75 degrees beneath hers and inserts one clasper, flexed ('splayed') medially 90 degrees, into her oviduct (Ref. 49562). A female displays 'back arching' and 'pectoral fin undulations' as precopulatory behavior to attract males (Ref. 49562).
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)
Κατάσταση Κόκκινου Καταλόγου IUCN (Ref. 130435: Version 2025-2 (Global))
Απειλή για τον άνθρωπο
Harmless
Ανθρώπινες χρήσεις
αλιεία: περιορισμένης εμπορικότητας; δόλωμα: occasionally
Εργαλεία
Ειδικές εκθέσεις
Λήψη XML
Διαδικτυακές πηγές
Εκτιμήσεις βάσει μοντέλων
Δείκτης φυλογενετικής ποικιλότητας (Αναφ. 82804) |
PD50 = 0.5039 [Uniqueness, from 0.5 = low to 2.0 = high]. |
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Bayesian length-weight
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a=0.00162 (0.00103 - 0.00256), b=3.27 (3.14 - 3.40), in cm total length, based on LWR estimates for this species & (Sub)family-body (Ref. 93245). |
Τροφικό Επίπεδο (Αναφ. 69278) |
3.9 ±0.3 se; based on diet studies. |
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Generation time |
5.5 ( na - na) years. Estimated as median ln(3)/K based on 1 growth studies. |
Ελαστικότητα (Αναφ. 120179) |
Χαμηλό, ελάχιστος χρόνος για διπλασιασμό πληθυσμού 4,5 - 14 έτη (K=0.20; Fec assumed to be <100). |
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Rate of population increase |
Prior r = 0.07, 95% CL = 0.04 - 0.10, Based on 1 full stock assessment. |
Ευπάθεια στην αλιεία (Ref. 59153) |
Moderate to high vulnerability (51 of 100). 🛈 |
Κατηγορία τιμής (Ref. 80766) |
Medium.
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