Quadrivisio sarina Lowry & Springthorpe, 2005, n.sp.
Creators: name: Lowry, JK
name: Springthorpe, RT
Publisher: name: Zenodo
Year: 2005
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Amphipoda
Maeridae
Quadrivisio
Quadrivisio sarina

description: Quadrivisio sarina n.sp.
Figs. 41–43
Type material. HOLOTYPE, ♀, 7.4 mm, AM P60482; 1 PARATYPE, ♂, 8.1 mm, AM P60484; 1 PARATYPE, ♀, AM P 60483, Armstrong Beach, Sarina, Queensland, Australia, [approx. 21°46'S 149°29'E], sand beach, mid-tide level, N. Hacking, 18 December 1994.
Type locality. Armstrong Beach, Sarina, Queensland, Australia, [approx. 21°46'S 149°29'E], sand beach, midtide level.
Description. Based on holotype female, AM P60482 and paratype male, AM P60484.
Head. Lateral cephalic lobes broad, rounded, with anteroventral notch or slit, anteroventral corner rounded. Antenna 1 shorter than antenna 2; peduncular article 1 longer than article 2, with 2 robust setae along posterior margin; flagellum with at least 14 articles; accessory flagellum with 6 articles. Antenna 2 peduncular article 2 cone gland reaching at least to end of peduncular article 3; article 4 subequal to article 5; flagellum with 15 articles. Mandible palp article 3 rectolinear, with setae mostly terminal, longer than article 1; article 2 subequal to or shorter than article 3; article 1 produced distally, shorter than article 2, about as long as broad. Maxilla 1 inner plate setose along entire inner margin.
Pereon. Gnathopod 1 coxa anteroventral corner not produced, posteroventral corner notch absent; merus without posterodistal spine; propodus palm nearly transverse, convex, without posterodistal corner, defined by posterodistal robust setae. Gnathopod 2 sexually dimorphic; subchelate; coxa posteroventral corner notch absent; merus with rounded posteroventral corner, or with subquadrate posteroventral corner; carpus compressed; propodus with medial depression, without strong concentration of setae, palm extremely acute, convex, smooth, lined with robust setae, defined by posterodistal robust setae, without posteroventral corner; dactylus apically acute/subacute. Pereopod 5–6 basis posterior margin convex, posteroventral corner narrowly rounded or subquadrate. Pereopod 7 basis posterior margin convex, with posterior margin smooth or minutely castelloserrate, posteroventral corner narrowly rounded or subquadrate.
Pleon. Epimeron 1 posteroventral corner with small acute spine. Epimera 1–2 posteroventral margin without spines above posteroventral corner. Epimeron 3 posterior margin smooth, posteroventral corner with small acute spine. Urosomite 1 with posterodorsal spine. Urosomite 2 with two groups of 1–3 small dorsolateral robust setae. Uropod 3 inner ramus subequal in length to outer ramus; outer ramus longer (1.2 to 2× length) than peduncle, 1-articulate. Telson with 1 robust seta per lobe on inner margins, each lobe with 3 or more apical/subapical robust setae, apical conical extension absent.
Female (sexually dimorphic characters). Gnathopod 2 merus with sharp posteroventral spine or with subquadrate posteroventral corner; propodus without medial depression, defined by posteroventral corner or without posteroventral corner.
Habitat. Marine; littoral; intertidal sand beach, mid-tide level.
Etymology. Named for the Queensland town of Sarina, near the type locality of the species.
Remarks. This is the first record of Quadrivisio in Australian waters. It is most similar to Q. bengalensis Stebbing, 1907, in having robust setae on the inner margins of the telson. Quadrivisio sarina differs from that species in the shape of the basis of pereopod 7 and in the shape of the palm of gnathopod 2. The antennae and rami of uropod 3 are generally less setose in Quadrivisio sarina.
Distribution. Queensland: Armstrong Beach, near Sarina (AM).
Australian geographic areas. Northeastern Australia.
description: Published as part of Lowry, JK & Springthorpe, RT, 2005, New and Little-known Melitid Amphipods from Australian Waters (Crustacea: Amphipoda: Melitidae), pp. 237-302 in Records of the Australian Museum 57 on pages 278-280, DOI: 10.3853/j.0067-1975.57.2005.1463, http://zenodo.org/record/15323482