Paraeuchaeta alaminae (Park 1975)

Euchaeta alaminae

MATERIAL.—A female from the R/V Alaminos cruise 73-A-7, station 6, 20°41′N and 84°17′W in the western Caribbean Sea, 2900-0 m, deposited as holotype in the National Museum of Natural History, Smithsonian Institution, under the catalog number of the United States National Museum (USNM 150969).

FEMALE.—Body length, 6.35 mm. Prosome length, 4.58 mm. Forehead (Figure 20a) with a distinct frontal eminence bearing suprafrontal sensilla. Rostrum large, pointing obliquely forward. Laterally, posterolateral corners of metasome smoothly rounded but somewhat squarish when viewed dorsally or ventrally. Dorsally. genital segment symmetrical, with lateral sides moderately swollen at the middle. Laterally, dorsal side of genital segment markedly convex dose to proximal end (Figure 20b,d. Genital prominence high, occupying about middle of segment. Anterior side of genital prominence highly convex and posterior side nearly perpendicular to ventral wall of segment. Laterally, genital flange appearing like a three-lobed structure. Ventrally (Figure 20c), genital flange with a large posterior lobe extending medially. Viewed laterally, posterior edge of genital field produced posteriorly to form a low ridge midway on posterior side of genital prominence. Appendicular caudal setae géniculated, not thicker than other caudal setae.

Antennule reaching distal end of prosome. Outer coxal lobe (Figure 20e) of maxillule with 5 long setae. None of six apical setae of maxilla provided with long, widely separated spines in addition to fine spinules. First two exopodal segments of first leg fused (Figure 20f). External spine of first segment minute, that of second segment short of reaching middle of third segment. Endopod of second leg 1-segmented. External spines of exopodal segments (Figure 20g) well developed, that of second segment being the largest. Incision posterior to second external spine of third segment not unusually deep.