Raja nidarosiensis

Author: Storm, 1881

Raja (Dipturus) nidarosiensis Storm, 1881

Status in World Register of Marine Species:
Accepted name: Dipturus nidarosiensis (Storm, 1881) (updated 2009-06-25)

Diagnosis: snout very long and pointed, disc broadly rhombic with acute outer corners, anterior margins deeply concave. Upper surface predominantly smooth, partially prickly only on head and along anterior margins of disc. No thorns on disc, at most 6-10 small thornlets sometimes present around inner margin of eyes; a row of 40-50 small thorns along tail, flanked occasionally by parallel rows in large females, 1-3 small thorns between separate dorsal fins; underside almost entirely covered with rough prickles. Colour: upper surface plain dark greyishbrown, mucous pores marked black; underside a slightly darker plain brown, mucous pores marked black and in moderate number only, the disc usually covered with a firm thick layer of black mucus, which masks both the real colour and the black pores. Size: to more than 200 cm TL; no data on young specimens.

Habitat: benthic in slope waters from about 200 m to more than 1,000 m; rare. Food: all kinds of bottom animals. Reproduction: oviparous; eggcases 200 by 100 mm (average, excluding horns).

Distribution: fjords of central and southern Norway, slopes off southern Iceland, off south-western Ireland and around Rockall Trough.

Complementary iconography. Clark, 1931, in Faune ichthyol. Atl. N., fiche 56.
Eggs, embryonic and young stages. Williamson, 1913: 1, fig. 7 (egg-capsule) | Nordgaard, 1917: 34-38, fig. 10-11 (egg-capsule) | Boeseman, 1967: 457-460, fig. 1 (eggcapsule).