“Joeropsis sanctipauli n. sp.
Material. - Sta 24, holotype, MNHN Is. 2771, ♂ 2.0 mm ; paratype, MNHN Is. 2772, ♀ 2.2 mm. Sta 19, paratypes, USNM 211481, 2 ♂, 2.0 mm, 2.2 mm.
Description
Body about 3.5 times longer than wide, integument brittle. Cephalon with anterolateral angles subacute, rostrum evenly convex, eyes poorly pigmented. Pereon parallel-sided, pereonite 1 longest, with anterior region broadly convex dorsally. Pleon width subequal to median length, lateral margins with 5 or 6 teeth, posterior margin between uropodal bases convex.
Antennule of 8 articles, basal article equal in length to articles 2 and 3 together ; antepenultimate and penultimate articles each with single aesthetascs, terminal article with 2 aesthetascs. Antenna] peduncle of 5 articles, articles 4 and 5 relatively elongate ; flagellum of 9 articles, basal article equal in length to rest of flagellum. Mandibular palp of 3 articles, article 2 longest, with 4 spines in distal half, article 3 with about 10 spines in distal half ; incisor process of 5 cusps ; spine row having 8 spines ; molar slender, elongate, distally narrowly rounded. Maxilla 1, inner ramus with 3 slender terminal setae ; outer ramus with 12 strongly dentate distal spines. Maxilla 2, inner ramus with 3 simple setae and several fine setules distally ; both lobes of outer ramus bearing 4 elongate fringed setae. Maxillipedal endite broad, bearing 3 coupling hooks on mesial margin, distolateral margin weakly serrate, mesiodistally emarginate, with 4 stout flattened spines ; palp of 5 articles, article 2 broadest and longest, with rounded mesiodistal lobe ; article 3 also with mesiodistal lobe ; article 4 elongate, slender ; article 5 small, about one-sixth length of article 4 ; epipodite lanceolate. Pereopods similar, sparsely setose, with propodi and carpi elongate-cylindrical, dactylus with 2 terminal ungui. Operculum of female distally broadly rounded. Pleopod 1 of male, rami fused mesially for about three-fourths of length, laterodistal lobe triangular, acute, mesiodistal lobe broadly rounded and bearing about 10 marginal setae. Pleopod 2 in male with lateral margin of triangular protopod setose ; exopod a short blunt lobe : endopod with distal article produced, tapering, reaching level of protopod apex. Pleopod 3 with broad endopod bearing one plumose seta mesiodistally, 2 plumose setae laterodistally ; exopod of 2 articles, distal article distally narrowed, articulating obliquely, lateral margins of both articles setose. Uropodal protopod lacking hook or spine, exopod about half length and width of endopod, both rami bearing elongate setae.
Depth Distribution. - 1 60-1 65
Etymology.- The specific name is derived from the type locality, St. Paul Island.
Remarks
Of the seven species of Joeropsis recorded from the southern or south-western Indian Ocean (see KENSLEY, 1975, 1984), only J. waltervadi Kensley, 1975, shows the combination of a pleon having dentate margins and a uropod lacking a protopodal spine or hook, as seen in the present species. These two species can be separated on several features : J. waltervadi has well pigmented eyes, a robust basal flagellar article of the antenna, the rostrum anteriorly slightly concave, the pleon wider than long, the mesiodistal lobe of pleopod 1 in the male acute-triangular, the distal article of the exopod of pleopod 3 relatively slender ; J. sanctipauli has weakly pigmented eyes, a slender more cylindrical basal flagellar article of the antenna, an evenly convex rostrum, a pleon as wide as long, a broadly rounded mesiodistal lobe of pleopod 1 in the male, and a relatively broad distal article of the exopod of pleopod 3.”
(Kensley, 1989: 153-155)
