Common Name
Antarctic Starry Skate
Year Described
Norman, 1938
Identification
Body relatively thick and heavy. Disk diamond-shaped with a concave anterior margin (more so in males). Snout fairly short. Rostral cartilage stiff. Eyes small. Pectoral fins angular to bluntly rounded. Pectoral skeleton does not reach snout tip, leaving a semi-translucent area adjacent to rostral cartilage. Anterior pelvic fin lobe much smaller than the posterior lobe and separated by a shallow notch. Tail is thickened, about 80% of TL, and has skin folds on both sides. There are two dorsal fins, separated from each other by a distance less than first dorsal base. The caudal fin is very small. Upper jaw with 33-44 tooth rows. Clasper very stout and broad.
Body covered with dermal denticles dorsally. Ventrum smooth. There are around 3 orbital thorns. There are 2-3 scapular thorns. There are 1-2 nuchal thorns. The abdomen and tail have a row of 20-28 thorns. Body thorns are very large, especially in young, with conspicuous stellate bases. Scattered small thorns on rest of body, including malar, alar patches (male), snout, base of pectoral fin, and bands on either side of tail. There are 0-1 thorns between the dorsal fins.
Color
Adults range from pale gray-brown to dark brown, with variable markings. Markings range from absent, to mottled with pale reticulations, to dark spotting over a paler background. Younger specimens have a bolder, more contrasting pattern (illustrated). Ventrum whitish with thick gray margins on the posterior part of disk and on abdomen. Underside of tail white with a gray stripe.
Size
Maximum size to 115cm TL.
Habitat
Found in sub-Antarctic waters on shelf and upper slopes (20-350m).
Range
Found mainly in the Southern Ocean off the Antarctic Peninsula and the Scotia Arc. It has been captured further north to off Argentina and the Falkland Islands.
References
Last, P.R., White, W.T., Carvalho, M.R. de, Séret, B., Stehmann, M.F.W & Naylor, G.J.P (Eds.). 2016. Rays of the World. CSIRO Publishing, Melbourne.
Other Notes
The only species of Amblyraja found in sub-Antarctic waters.
There is a complex of similar skates in the genus Amblyraja in the Patagonian region that are difficult to separate using morphology and coloration is possibly the most useful character. The pale-bellied Amblyraja doellojuradoi and A. georgiana are partially sympatric in the Patagonian region with the latter being more common in the southern ocean. The existence of the widespread pale-bellied A. hyperborea in the South Atlantic is unclear and would complicate identification. Amblyraja frerichsi is sympatric with A. doellojuradoi but has a characteristic dark ventrum. Records of Amblyraja taaf in the SW Atlantic are misidentifications of other pale-bellied Amblyraja.