Elasmopus varanocephalensis Lowry &amp; Hughes 2009, sp. nov.
Creators: name: Lowry, J. K.
name: Hughes, L. E.
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Amphipoda
Maeridae
Elasmopus
Elasmopus varanocephalensis

description: <i>Elasmopus varanocephalensis</i> sp. nov. (Figs 13, 14) <b>Type material.</b> Holotype, male, 8.0 mm, AM P78067, south of Lizard Head, Lizard Island (14°41’S 145°27’E), rubble, 2 m, J.D. Thomas, 29 January 1989 (JDT / LIZ 14 c). <b>Type locality.</b> South of Lizard Head, Lizard Island, Queensland, Australia (14°41’S 145°27’E). <b>Etymology.</b> Named for the type locality, Lizard Head. <b>Description</b>. Based on holotype male, 8.0 mm, AM P78067. <b>Head.</b> <i>Head</i> eyes ovate; lateral cephalic lobe broad, truncated, anteroventral margin with notch/slit, anteroventral corner rounded. <i>Antenna 1</i> longer than antenna 2; peduncular article 1 subequal in length to article 2, without robust setae along posterior margin; article 2 longer than article 3; accessory flagellum short, with 4 articles; flagellum with 21 articles. <i>Antenna 2</i> peduncular article 4 subequal in length to article 5; flagellum with 9 articles. <i>Mandible</i> incisor a smooth cutting edge with 2 apicomedial cusps; accessory setal row with 2 setae; palp well developed, 3-articulate; article 1 about as long as broad, shorter than article 2, inner margin not produced distally; article 2 shorter than article 3; article 3 long (4 x as long as broad), weakly falcate, longer than article 1. <b>Pereon.</b> <i>Gnathopod 1</i> coxa anteroventral corner produced, rounded, anterior margin concave; merus without posterodistal tooth; carpus about 2 x as long as broad, carpus subequal in length to propodus; propodus with setae in anterodistal bunches and along posterior margin; propodus palm acute, slightly convex, entire, defined by posterodistal corner, with posterodistal robust setae. <i>Gnathopod 2</i> coxa posteroventral corner notch absent; basis slender; merus with subquadrate distoventral corner; carpus compressed, projecting between merus and propodus, length 1 x breadth; propodus expanded, without setal bunches along posterior margin, palm acute, slightly convex, slightly sculptured, palm about one third length of propodus, with reduced subtriangular distomedial shelf, with 6 robust setae on shelf, without midmedial excavation, palmar margin lined with a row of 6 robust setae, without teeth, subpalmar surface with short proximal subpalmar seam forming two nodules, without posteroventral corner, with posterodistal robust setae; dactylus reaching end of palm, closing along palm, without setae on anterior margin, without posteroproximal shelf, apically blunt. <i>Pereopod 4</i> coxa posteroventral lobe slightly developed, with rounded posteromedial corner. <i>Pereopod 5</i> basis slightly expanded, posterior margin straight, without long slender setae, posteroventral corner narrowly subquadrate; carpus and propodus without long, slender setae along anterior margin. <i>Pereopod 6</i> basis posterior margin straight, minutely castelloserrate, without long slender setae, posteroventral corner narrowly rounded; carpus and propodus without long, slender setae along anterior margin; merus and carpus not broadened; propodus slightly expanded posterodistally to from a hood-like projection. <i>Pereopod 7</i> basis posterior margin convex, with posterior margin minutely castelloserrate, not produced posterodistally, without long slender setae, posteroventral corner broadly rounded; merus and carpus not broadened; propodus expanded posterodistally to from a hood-like projection. <b>Pleon.</b> <i>Pleonites 1–3</i> dorsally smooth, without setae, spines or carinae. <i>Epimeron 1</i> posteroventral corner with small acute spine. <i>Epimeron 2</i> posteroventral corner with small acute spine. <i>Epimeron 3</i> ventral margin smooth, posteroventral margin smooth, posteroventral corner with small acute spine. <i>Urosomites 1–3</i> dorsally smooth, without setae, spines or carinae. <i>Uropod 1</i> peduncle with basofacial robust seta. <i>Uropod 3</i> rami distally rounded, apical robust setae long or short; inner ramus subequal in length to outer ramus; inner ramus long (length 2 to 2.5 x breadth); outer ramus short, length 2.2 x breadth, longer than peduncle, 1-articulate. <i>Telson</i> deeply cleft (more than 66%), longer than broad, tapering distally, each lobe with long inner and short outer apical cusps, apical conical extension reaching at least halfway along longest seta, without dorsal robust setae, with apical/subapical robust setae, each lobe with 2 long and short apical robust setae, without robust setae on outer and inner margins. <b>Female</b> (sexually dimorphic characters). Unknown. <b>Habitat.</b> Marine, epibenthic, living in coral rubble. <b>Remarks.</b> <i>Elasmopus varanocephalensis</i> <b>sp. nov.</b> is most similar to <i>E. alalo</i> Myers, 1986b, <i>E. spinicarpus</i> Berents, 1983 and <i>E. seticarpus</i> Myers, 1985. All of these species have an elongate, deeply cleft telson with short subapical setae and a relatively plain palm on male gnathopod 2. <i>Elasmopus varanocephalensis</i> differs from <i>E. alalo</i> in having a very reduced distomedial shelf, no midmedial excavation, a single row of robust setae on the palm and two subpalmar nodules of male gnathopod 2. It differs from <i>E. spinicarpus</i> in the presence of a weak posterodistal shelf on male gnathopod 2. Although the palms are more similar between <i>E. varanocephalensis</i> and <i>E. seticarpus</i>, the extremely setose carpus of male gnathopod 2 in <i>E. seticarpus</i> distinguishes these species. <b>Distribution.</b> <i>Australia</i>. Queensland: Lizard Island (current study).
description: Published as part of <i>Lowry, J. K. &amp; Hughes, L. E., 2009, Maeridae, the Elasmopus group *, pp. 643-702 in Zootaxa 2260 (1)</i> on pages 666-669, DOI: 10.11646/zootaxa.2260.1.33, http://zenodo.org/record/5361655
description: {"references": ["Myers A. A. (1986 b) Amphipoda from the South Pacific: Tonga. Records of the Australian Museum, 38 (5), 271 - 289.", "Berents, P. B. (1983) The Melitidae of Lizard Island and adjacent reefs, The Great Barrier Reef, Australia (Crustacea: Amphipoda). Records of the Australian Museum, 35, 101 - 143.", "Myers, A. A. (1985) Shallow-water, coral reef and mangrove Amphipoda (Gammaridea) of Fiji. Records of the Australian Museum, Supplement, 5, 1 - 143."]}