Raja radula

Author: Delaroche, 1809

Raja (Raja) radula Delaroche, 1809

Status in World Register of Marine Species:
Accepted name: Raja radula Delaroche, 1809 (updated 2009-06-25)

Diagnosis: snout short and obtuse. Upper surface covered with coarse spinules; underside in juveniles and adult males spinulose only on snout and on hind half of tail, large females also prickly around mouth, along
mid-body, and on front half of tail. Vague separate thorns present along inner margin of eye; an irregular row of numerous small thorns from nape to first dorsal fin, interrupted on body in large specimens; 2 thorns between dorsal fins. Colour: upper surface light greyish-brown, with pattern of scattered dark spots and lines, as well as light dots on disc; a constant large circular eye- spot, its dark centre encircled by a yellowish
ring and a broad outer dark ring with light dots, placed on either side of body at level of greatest width of disc; underside white, with pale grey margins to disc and several dark spots on tail. Size: to about 70 cm TL.

Habitat: benthic, from coastal waters to about 300 m; rather common, locally exploited. Food: all kinds of bottom animals. Reproduction: oviparous; throughout year, maximum number of egg-cases laid in late spring and summer, embryos developing in about 4 months; egg-cases 51-57 by 34-37 mm (excluding horns).

Distribution: Mediterranean, mainly in western part, apparently passing into Atlantic (off northern coasts of Morocco). Elsewhere, records from the Gulf of Guinea most probably misidentifications.

Note: Raja atra Muller and Henle, 1841 was based on two specimens, of which the larger is R. radula; the smaller is another species. Placed in the sub-genus Raja by Capape and Desoulter (1978).

Complementary iconography. Clark, 1931, in: Faune ichthyol. Atl. N., fiche 40 Bini, 1967: 153-154.