Family AMPHILOCHIDAE Boeck, 1871

Amphilochus manudens, a non-Australian species

© Copyright from Barnard & Karaman 1991: fig. 24

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Introduction

The amphilochids are a cosmopolitan group of shallow-water, usually algal-dwelling amphipods. Only four of the 11 genera recognised by Barnard & Karaman (1991) are represented in Australian waters. There are four temperate algal-dwelling species and one rare tropical species associated exclusively with crinoids (Potts 1915).

Diagnosis

Head as long as deep, longer than deep or deeper than long; anteroventral margin straight or oblique; anteroventral corner subquadrate; rostrum short, moderate or long; eyes round or ovoid. Body laterally compressed; smooth. Antenna 1 shorter than or subequal to antenna 2; accessory flagellum present or absent; primary flagellum 5- or more articulate; callynophore present or absent. Antenna 2 short; flagellum shorter than or as long as peduncle; 5- or more articulate. Mandible incisor dentate; molar present or absent, fully triturating; palp present or absent. Maxilla 1 inner plate weakly setose apically; palp 1- or 2-articulate. Maxilliped inner plates well developed; outer plates very large, large or small. Coxae 1–4 longer than broad, overlapping. Coxa 1 or coxae 1–2 vestigial. Coxae 2–4 none immensely broadened. Gnathopod 1 not sexually dimorphic; smaller (or weaker) than gnathopod 2 or subequal to gnathopod 2; carpochelate or subchelate; coxa vestigial, hidden or partially hidden by coxa 2; carpus shorter than, subequal to, or longer than propodus, slightly, strongly, or not produced along posterior margin of propodus. Gnathopod 2 not sexually dimorphic; subchelate; coxa smaller than and mostly hidden by coxa 3, or subequal to but not hidden by coxa 3; ischium short; carpus short, shorter or longer than propodus, slightly or strongly produced along posterior margin of propodus. Pereopod 3 coxa longer than broad; carpus subequal to propodus, not produced. Pereopod 4 coxa larger than coxa 3, with well-developed posteroventral lobe; carpus subequal to propodus, not produced. Pereopod 5 subequal to pereopod 6; coxa subequal to coxa 4, without posterior lobe; basis expanded, subovate, without posteroventral lobe; carpus linear. Pereopod 6 subequal to pereopod 7; basis expanded. Pereopod 7 subequal to pereopod 5; basis expanded, subrectangular or subovate. Urosomite 1 longer or much longer than urosomite 2. Uropods 1–2 apices of rami without robust setae. Uropod 3 biramous; peduncle long; rami styliform; outer ramus longer than peduncle; inner ramus not apically setose. Telson laminar or weakly thickened dorsoventrally; emarginate or entire; longer than broad; dorsal and apical robust setae absent.

General References

Barnard, J.L. & Karaman, G.S. 1991. The families and genera of marine gammaridean Amphipoda (except marine gammaroids). Records of the Australian Museum, Supplement 13: 1-866

Boeck, A. 1871. Crustacea Amphipoda Borealia et Arctica. Bulletin of the Mauritius Institute 1870: 81-280 i-viii

Potts, F.A. 1915. The fauna associated with the crinoids of a tropical coral reef: with especial reference to its colour variations. Papers from the Department of Marine Biology of the Carnegie Institution of Washington 8: 71-96 pl. 1

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