Eurycyde antarctica Child 1987

“Eurycyde antarctica, new species Fig. 4

Material examined. —E of Adare Penin­sula, Ross Sea. Antarctica, 72°00'S. 172°28'E, 523-528 m. coll. Eltanin, sta 1997, 10 Jan 1968, holotype male, USNM 233606, paratype female, USNM 233607; NE of Cape Adare, Ross Sea, 71°17'S, 171°33'E. 659-714 m, coll. Eltanin, sta 1870, 14 Jan 1967. paratypes. 1 female. 1 juvenile, USNM 233608.

Description.—Size typical for genus, leg span slightly over 10 mm. Trunk robust. glabrous, completely segmented, each seg­ment inserted anteriorly into swollen cowl of posterior of first 3 segments. Lateral pro­cesses moderately short, only 1.5 times as long as wide, separated by their diameters, armed with short, narrow, dorsodistal tu­bercles only half as tall as segment diame­ters, without setae or spines. Ocular tubercle with broad base tapering to slender ante­rior-pointing tip, glabrous, with lateral sen­sory papillae projecting as tiny slender tu­bercles, eyes darkly pigmented, of equal size, posterior pair placed distally to anterior more proximal pair. Oviger implantation directly ventral to ocular tubercle, at mid­point of first trunk segment. Proboscis of typical 2 segments, proximal segment cylin­drical, half distal segment length. Second segment carried ventrally from narrow at­tachment to first segment, swollen at mid-length, ovoid, with very narrow pointed mouth. Abdomen cylindrical, tapering dis­tally, as long as midlength of second coxae of fourth legs, armed distally with 4 short setae, without long spines.

Chelifore scape 2-segmented, slender, long, extending to midlength of second pro­boscis segment, armed with 2-3 long broad spines on first segment which is 0.2 times longer than second segment. Second seg­ment armed with 2-3 long spines similar to those of first segment. Chela tiny, with short, broad, curved immovable finger and tiny bud as movable linger, glabrous.

Palp 9-segmented, second segment long­est, about 0.3 longer than fourth segment. Fifth segment shortest, not longer than wide. Terminal 5 segments subequal in length to fourth, terminal 4 with fields of ventral setae equal to or slightly longer than segments.

Oviger fairly long, major segments armed with few short, lateral, recurved setae. Fifth segment 0.85 as long as fourth, sixth half length of fifth. Strigilis 4 segments each shorter than last, armed with distal ectal seta each and 2 rows of endal denticulate spines in the formula (counting both rows), 9:6:5:7, with almost straight terminal claw lacking teeth. Denticulate spines narrow, with 5-6 denticles per side.

Legs slender, major segments each nar­rower than last distally, armed with few very long broad spines and several long pointed spines, with 1-2 pointed spines on tibiae having setules or "feathered." First coxae without tubercles of any description. Tibiae

subequal in length. femorae slightly shorter. Cement gland a small swelling proximally, at 0.25 femur length. with short tube point­ing obliquely anterior and distally. Tarsus 0.33 length of propodus. Propodus very slightly curved. without heel or heel spines, armed with many short sole spines. Claw broad, well curved, less than 0.3 propodal length, no auxiliaries.

Female slightly larger in most measure­ments. Legs with several more feathered sharp spines. Ova carried in very swollen second coxae, none found in femorae. Ocu­lar tubercle with short blunt anterior tuber­cle half as tall as that of male. Neck shorter than male's, and lateral process tubercle shorter and broader based.

Measurements (in mm).—Trunk length (chelifore insertion to tip 4th lateral pro­cesses) 1.33; trunk width (across 2nd lateral processes) 0.86; proboscis length (second segment only) 0.84; abdomen length 0.55: third leg, coxa 1 0.23; coxa 2 0.56; coxa 3 0.25; femur 0.95; tibia 1 1.0; tibia 2 1.0; tarsus 0.14; propodus 0.43; claw 0.12.

Distribution.—Known only from its type locality, off Cape Adare and its Peninsula, Ross Sea, in 523-714 nt.

Etymology.—This species is named for the Ocean in which it was collected.

Remarks. —Of the nine or ten recognized species of Eurycyde, this is the first known to have the following combination of char­acters; no ocular tubercle spines or setae, and no tubercles on the first coxae. It is also the first species of the genus to be found in Antarctic waters. Most known species are from tropical or at least tropical-temperate habitats. The only cold water species known was the first to be described; E. hispida (Kroyer), distributed from eastern Canada to the western Russian Arctic. This new species and E. hispida could be classified as the 'conservative' element of this genus be­cause they both lack the long ocular tubercle spines and the spinose first coxae tubercles of many other species. The new species has very few long broad spines on any appendage, in contrast to the many spines on most species. The cement gland bulge and tube of the new species are smaller than those of most species where the male gland is known, and is close to those of E. hispida. This new species differs from any other, including E. hispida, in having much less spinose ap­pendages and very different lateral process tubercles in a genus where most species have very slender pointed tubercles or none at all. All species of this genus are closely allied in characters such as oviger, palp, chelifore, and terminal leg segment lengths and shapes. No known Eurycyde species has the long pointed ocular tubercle without spines or setae present in this new species.” (Child 1987, 909-912)

Eurycyde antarctica là một loài nhện biển trong họ Ascorhynchidae. Loài này thuộc chi Eurycyde. Eurycyde antarctica được miêu tả khoa học năm 1987 bởi Child.