Metacyproidea makie Ariyama, 2016, sp. nov.
Creators: name: Ariyama, Hiroyuki
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Amphipoda
Cyproideidae
Metacyproidea
Metacyproidea makie

description: Metacyproidea makie sp. nov.
[Japanese name: Makie-hoteiyokoebi, new] (Figs 12–16)
Material examined. Holotype: female with larvae (OMNH-Ar-9956), 7.9 mm, point "Kyu-yaeneko", Hachijo Island, Tokyo Prefecture, 33°05'41"N, 139°46'14"E, 3 m in depth, on seaweeds, using SCUBA, 8 July 2012, coll. K. Tanaka. Paratypes: 3 ovigerous females and 1 female with larvae (OMNH-Ar-9957–9960), 6.9, 6.2, 5.7, 5.1 mm, same data as holotype.
Description. Female [based on holotype, 7.9 mm (OMNH-Ar-9956)]. Body (Fig. 12) oval; head a little longer than pereonite 1, eyes medium-sized, diameter 44% length of head; pereonites 4–5 long, posteroventral corners of pereonites 5–7 protruded; coxa 5 barely reaching posteroventral corner of pereonite 6; pleonites 1–3 each with dorsolateral ridge extending to urosomite 1; urosome slender.
Antenna 1 (Fig. 13 A, A1) short, with ratio of lengths of peduncular articles 1–3 1:1.2:0.5, tooth of article 2 occupying quarter of whole length; accessory flagellum vestigial, with 4 setae; primary flagellum with 16 articles, articles 1–15 with 2, 1, 2, 3, 4, 2, 2, 2, 2, 2, 2, 2, 0, 1, 1 aesthetascs at each distal end. Antenna 2 (Fig. 13 B) short, with ratio of lengths of peduncular articles 3–5 1:1.5:1.4; flagellum with 3 articles.
Upper lip (Fig. 13 C) widely expanded anterodorsally, ventrolateral margins with short setae. Mandible (Fig. 13 D, D1, E, E1), incisor bearing 9 cusps, left lacinia mobilis longish triangular, distal margin bearing 8 cusps, right lacinia mobilis lacking, number of accessory blades 16 in left and 18 in right; palp article length ratio 1:2.0: 1.6 in left and 1:1.8: 1.4 in right, dorsal margin of article 1 bearing many short setae, medial surfaces of articles 2–3 covered with short setae, tip of article 3 with 1 long seta. Lower lip (Fig. 13 F), inner lobes distinct; anteromedial surfaces of outer lobes heavily setose, each with 1 truncate projection on corner, mandibular processes small. Maxilla 1 (Fig. 13 G, G1), inner plate rounded, distal margin setose; mediodistal corner of outer plate acutely projected, distal margin with 7 robust setae, medial margin heavily setose; distal end of palp with 3 minutelyserrated robust setae and 3 robust setae, laterodiatal margin heavily setose. Maxilla 2 (Fig. 13 H), inner plate longer and wider than outer, terminal ends of inner and outer plates with 4 and 2 thick setae, respectively, dorsal surfaces of both plates heavily setose. Maxilliped (Fig. 13 I, I1 – 2), distal margin of inner plate setose, with 3 robust setae; outer plate setose laterally, with 3 distal robust setae; ventral surfaces and medial margins of palp articles 1 – 2 setose, mediodistal corner of article 3 with 1 plumose seta, articles 3 – 4 covered with short setae dorsally, article 4 slender.
Gnathopod 1 (Fig. 14 A, A1–2), coxa trapezoidal, anterior margin with many short setae, ventral margin bearing 2 setae; basis long, distal half swollen anteriorly; ischium setose posteriorly, posterodistal corner not projected; merus short; carpus medium length, posteromedial surface covered with thin setae, posterodistal corner protruded, lateral and medial surfaces of tip bearing 6 and 2 long setae, respectively; propodus long, stout, about 1.4 times as long as carpus, palm with many short setae, anteromedial surface covered with thin setae; dactylus long, slightly curved, posterior margin without spines, medial surface bearing row of thin setae. Gnathopod 2 (Fig. 14 B, B1), coxa trapezoidal, anteroventral corner produced, with a few short setae; oostegite long, distal margin with many long setae; ischium short, posterodistal corner strongly projected, with many setae; merus short; posterodistal projection of carpus longer than carpus proper, almost reaching posterodistal corner of propodus, medial surface bearing 1 robust short seta and 5 normal setae, posteromedial surface covered with thin setae; propodus relatively wide, palm with many blunt denticles; dactylus short, almost straight, gradually narrower, posterior margin smooth.
Pereopod 3 (Fig. 14 C), coxa triangular, anterior margin rounded, posterior margin slightly concave, posteroproximal and posteroventral corners each with small projection; distal part of oostegite wide, margin with many setae; basis relatively long. Pereopod 4 (Fig. 14 D), coxa extremely wide, swollen posteriorly, anterior margin slightly convex, with small hollow on anteroventral corner, ventral margin also slightly convex, posteroproximal corner a little projected; oostegite same as pereopod 3; basis relatively long. Pereopod 5 (Fig. 14 E), coxa lanceolate, width about 3.1 times of length, anteroproximal corner slightly projected, middle anterior margin with small hollow, posterior end pointed; oostegite short, with 8 setae; basis and merus – propodus long. Pereopod 6 (Fig. 14 F) shorter than pereopod 5; coxa parallelogramatic, width about twice of length; basis long. Pereopod 7 (Fig. 14 G, G1) a little shorter than pereopod 6; coxa rhomboidal, short; basis long.
Pleonal epimera (Fig. 15 A), epimera 1–2 each with oblique lateral ridge; posteroventral corners projected bluntly in epimeron 1, projected acutely in epimeron 2, and rounded in epimeron 3; all ventral margins bare. Pleopods (Fig. 15 B – D), pleopod 3 a little shorter than pleopods 1–2; peduncles bearing several setae; inner and outer rami with 13, 13, 11 and 14, 16, 15 articles in pleopods 1 – 3, respectively. Uropods (Fig. 15 E – G), peduncle and both rami without robust setae, but bearing minute denticles; peduncle of uropod 1 long, both rami 55% length of peduncle; uropod 2 about 0.8 times as long as uropod 1, both rami 63% length of peduncle; uropod 3 short, about 0.6 times as long as uropod 1, inner and outer rami 68% and 60% length of peduncle, respectively. Telson (Fig. 15 G) longish trapezoidal, breadth about 0.6 times of length, distal end slightly hollowed in middle, lateral and distal margins without setae.
Male unknown.
Coloration in life (Fig. 16). Head gold, eyes red; dorsal surfaces of pereonites with many white pigments, lateral surfaces of pereonites with many orange and several blue pigments on a brown background; coxae 3–4 similar to lateral surfaces, but with several large white marks.
Etymology. Referring to the coloration resembling makie, Japanese traditional craft.
Distribution. Japan: only Hachijo Island in Tokyo Prefecture (Fig. 1). Habitat. On seaweeds, 3 m in depth.
description: Published as part of Ariyama, Hiroyuki, 2016, Five species of the family Cyproideidae (Crustacea: Amphipoda) from Japan, with the description of a new genus and two new species, pp. 301-331 in Zootaxa 4097 (3) on pages 315-320, DOI: 10.11646/zootaxa.4097.3.1, http://zenodo.org/record/263937