thornback ray (RAJA CLAVATA)
Thornback Ray (RAJA CLAVATA) - European Federation of Sea Angling Records
is found in the Eastern Atlantic around Iceland and Norway, the North Sea and the western Baltic southward to Morocco and Namibia, including the Mediterranean and the Black Sea. Although reported from southern Africa, its status in the area is uncertain.
Thornback Rays inhabit shelf and upper slope waters from the coastal line to about 300 m. They can be found on sand and sand-rock bottoms. These rays feed on all kinds of bottom animals, preferably crustaceans. They are also oviparous. Distinct pairing with embrace.
Young may tend to follow large objects, such as their mother. Eggs are oblong capsules with stiff pointed horns at the corners deposited in sandy or muddy flats. Egg capsules are 5.0-9.0 cm long and 3.4-6.8 cm wide. Utilized fresh and frozen . About 52-170 eggs are laid per individual in a year. Maximum length for male is 105 cm TL.
There are a number of distinctive characteristics of the Thornback Ray: its upper surfaces are wholly prickly, underside wholly prickly in large females, only snout and margins of disc in young and large males; orbital thorns separate, 30-50 in median row from nape to first dorsal fin. Additional large 'buckler' thorns with swollen bases scattered on upper surface of disc in adults. Sub rhomboid disc, disc-width 1,25 to 1,36 times in its length, its length 1,70 to 1,83 times in total length; short rostrum, rounded at his extremity; pectoral fins with clear angles on lateral side; triangular pelvic fins. Upper surface very variable, all shades of brown, variegated with dark and light spots and blotches, underside white.
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