Ascorhynchus athernus Child 1982

Ascorhynchus athernum

MATERIAL EXAMINED.—North American Basin: Chain cruise 50, sta 76(HH), 39°38.3′N, 67°57.8′W, epibenthic sled, 2862 m, 29 Jun 1965 (1 holotype, USNM 181043; 1, 2 paratypes, USNM 181044).

DESCRIPTION.—Trunk oval, completely segmented. Posterior of first 3 trunk segments with extremely large bell-shaped cowl topped by tall conical median tubercle. Neck short, flaring anteriorly to broad anterior-pointing tubercles on anteriolateral margins. Lateral processes short, separated by about half their diameters, each armed dorsodistally with a slender conical anterior-pointing tubercle. Ocular tubercle tall, anterior-pointing, without eyes, with papillae mediolaterally. Abdomen long, distinctly segmented at base, carried ventrally at oblique angle.

Proboscis large, ovoid, with extremely blunt square oral surface.

Chelifore scape 1-segmented, thick, only about 3 times as long as wide, armed with several distal setae. Chela tiny, carried anaxially, with minute but apparently functional fingers, which cross at tips.

Palps with segments 2 and 4 equal, 4 distal segments approximately equal in length, armed with few ventral and lateral setae longer than segment diameter. Segment 3 no longer than wide.

Oviger segments 5 and 6 with lateral row of recurved spines. Segments 4 and 6 equal in length, segment 5 slightly longer. 4 terminal segments, the strigilis, armed with few lateral and dorsal setae and denticulate spines numbering 5:4:2:4, with unarmed terminal claw almost as long as terminal segment. Denticulate spines with 3 lobes per side.

Anterior and posterior leg segment lengths approximately alike, moderately long, slender, armed with dorsal, lateral, and ventral setae, none as long as the segment diameter. Tibia 1 the longest segment, with femur and tibia 2 equal in length. Tarsus 0.9 length of propodus, armed with very few dorsal and ventral setae. Propodus without heel or heel spines, armed with 3 to 5 small sole setae. Claw robust, 0.6 length of propodus. Femoral cement gland a single raised distally pointing cone at 0.6 the dorsal length of femur. Cement gland a prominent dark mass beneath cone. Sexual pores on posterior 4 legs.

Female: Prominent sexual pores on all 2nd coxae. Lateral processes and ocular tubercle with slightly shorter tubercles. Oviger with fewer setae.

MEASUREMENTS OF HOLOTYPE (mm).—Trunk length (anterior tubercle projections to tubercle tip 4th lateral process), 2.9; trunk width (across 2nd lateral process tubercle tips), 2.11; proboscis laterally, 2.14; abdomen laterally, 0.9; 3rd leg, coxa 1, 0.42; coxa 2, 1.29; coxa 3, 0.68; femur, 2.48; tibia 1, 3.1; tibia 2, 2.4; tarsus, 0.8; propodus, 0.94; claw, 0.58.

DISTRIBUTION.—The proposed species is known only from its type-locality, the North American Basin, in 2862 meters.

ETYMOLOGY.—The specific name athernum is Greek (armed with spikes), pertaining to the large lateral process and middorsal and anteriolateral cephalic segment tubercles.

MATERIAL EXAMINED.—Argentine Basin, SE of Rio de la Plata: Atlantis II cruise 60, sta 237, 36°32.6′S, 53°23.0′W, epibenthic sled, 993–1011 m, 11 Mar 1971 (1). Sta 240, 36°53.4′S, 53°10.2′W, epibenthic sled, 2195–2323 m, 12 Mar 1971 (1).

Ascorhynchus athernum là một loài nhện biển trong họ Ascorhynchidae. Loài này thuộc chi Ascorhynchus. Ascorhynchus athernum được miêu tả khoa học năm 1982 bởi Child.