Parelasmopus setiger Chevreux 1901

Parelasmopus setiger Chevreux

?Megamoera suensis Haswell, 1880c:335–336, pl. 21: fig. 5.

Megamoera suensis.—Miers 1884:317—318.

Megamoera haswelli Miers, 1884:318 [name in text].

Not Megamoera suensis.—Haswell 1885:103–104, pl. 15: figs. 1–4 [= Maera hamigera (Haswell) fide Stebbing, 1906, but see Stebbing, 1910a: 600].

Elasmopus suensis.—Stebbing, 1906:442–443.

Parelasmopus setiger Chevreux, 1901:412–418, figs. 32–39.

Parelasmopus suluensis.—Chilton 1922:7–8, fig. 3 [not Dana]. ?Parelasmopus suluensis.—Walker 1904:278, pl. 6: fig. 3 [?not Dana].

DISTRIBUTION.—Tropical Australia, Indonesia, and northern Indian Ocean; littoral and sublittoral.

Based on male, 10.3 mm, UKMMZ-1527. Head. Head slightly longer than pereonites 1–2 combined; rostrum small; lateral cephalic lobe broad, moderately produced, anteroventral margin with notch/slit; eyes well developed, ovate. Urosomite 1–3 serrated dorsally. Antenna 1 longer than antenna 2; peduncular article 1 subequal to article 2, with 2 robust setae along posterior margin, ventrodistal margin with 1 group of robust setae and 2 fine setae; article 2 with several fine setae along both margins; flagellum articles broader than long, with 18+ articles (broken); accessory flagellum minute, with 3 plus one rudimentary article. Antenna 2 peduncular article 2 cone gland reaching beyond peduncular article 3; article 4 longer than article 5; flagellum with 11 articles. Upper lip semicircular, pubescent. Lower lip outer lobes with two pairs of ducts, mandibular lobes apically subacute. Maxilla 1 inner plate subtriangular, with 2 apical plumose setae; outer plate armed with 6 serrate robust setae, facial side with row of 5 serrate robust setae; palp biarticulate, article 1 shorter than article 2, article 2 with 6 thick setae terminally. Maxilla 2 outer plate slightly broader than inner plate; inner plate armed with 13 mostly long setae from distal end to inner half margin; outer plate with 10 setae only on apex. Mandible (left), incisor armed with 4 teeth; lacinia mobilis serrate apically; accessory setal row well developed and composed of 4 setae and 1 broad plate; molar process well developed, triturative, provided with 2 plumose setae and 1 stout seta; mandibular condyle well developed; palp triarticulate, article 1 distally swollen, article 2 short almost 2.5 times as long as article 3, article 3 and apically provided with 1 couple of long setae. Pereon. Gnathopod 1 smaller than gnathopod 2; coxa 1 anterior margin concave, produced forward anteroventrally, posteroventral corner notched; basis anterior margin straight with 3 short robust setae along the margin, posterodistally provided with several plumose setae, posterior margin with several long setae on mid length; ischium subcyclindrical, about 33% as long as basis, posterodistally provided by 3 plumose and 2 medium length setae; merus slightly longer than ischium with a row of short and long setae on distal half; carpus as long as propodus, anterodistally with 3 long and 2 short setae, medial surface with rows of pectinate setae; propodus medial surface with comb, palm convex defined by 1 pronounced spine, marginally provided with about 7 bifid small spines and many minute setae; dactylus falcate, overlapping palm. Gnathopod 2 coxa 2 subquadrate, posteroventral corner notched; basis slender with slight excavation along anterior margin, anterodistal corner subquadrate, posterior margin with medium length setae on mid length; merus acutely produced distoventrally; carpus compressed, subtriangular, posterior expansion densely setaceous in rows, anterodistally with 2 stout setae; propodus expanded and subrectangular, posterior margin with thick setae, palm transverse, defined by 9 robust setae along the palmar margin, deeply concave medially; dactylus falcate, with crenulated posteroproximal shelf. Pereopods 3–4 coxa 3 produced forward on ventral half part of anterior margin. coxa 4 broader than deep, posteroventral lobe well developed, with subrectangular posteromedial corner. Pereopods 3–4 similar except for pereopod 3 shorter; carpus posterodistally provided with 2 or more prominent robust setae; propodus posteriorly provided with row of short robust setae. Pereopods 5–7 coxae concave, both anterodistally and posterodistally, basis slightly expanded, posterior margin crenulate, without long slender setae, except for pereopod 7; merus and carpus not broadened; carpus and propodus with, slender setae along posterior margin; propodus not expanded posterodistally; dactylar ungues simple. Urosome. Urosomite 1–3 dorsally bicarinate. Epimeron 1–3 posteroventral corner with small acute spine. Epimeron 3 ventral margin serrate distally, posteroventral margin serrate below posteroventral corner, posteroventral corner with strongly produced acute spine. Uropod 1 extending beyond peduncle of uropod 3; peduncle longer than rami, outer-ventrodistally provided with 1 robust seta, upper margin with 8 inner and 9 outer robust setae; rami subequal, truncate, apically provided with 1 pronounced and 2 robust setae, outer ramus with 3 outer robust setae, inner ramus with 4 outer small setae and 3 inner median robust setae. Uropod 2 not extending beyond peduncle of uropod 3; peduncle shorter than rami, upper-marginally provided with 5 median robust setae, 1 inner-distal robust seta; rami subequal, truncate, outer ramus provided with 4 median robust setae, 1 distal robust seta and 1 apical robust seta, inner ramus provided with 10 inner median and 3 inner distal robust seta, and 1 apical robust setae. Uropod 3 peduncle 33% as long as outer ramus, provided with 2 outer, 3 inner and 2 distal robust setae; rami foliaceous, both rami distally truncated to subacute, with long and short apical robust setae. Telson broader than long, small, 5/6 cleft, each lobe with slight ridges on central line, with 7 distal robust setae. Female (dimorphic characters). Based on female, 9.8 mm, UKMMZ-1528. Gnathopod 2 carpus relatively long about, 1.5 times as long as wide, slightly lobate; propodus linear, almost five times as long as broad, without distomedial shelf; dactylus apically subacute.

Seychelles, Philippine Islands, Sulu Sea, Indonesia, Gulf of Thailand, Australia, north Indian Ocean and Singapore (current study).