Australian Amphipoda: Aoridae

J.K. Lowry, P.B. Berents & R.T. Springthorpe

Aora hebes Myers & Moore, 1983: 172, figs 1, 9, 10, 13.

Type material. HOLOTYPE: male, 6.5mm, AM P22411. PARATYPES: 18 males, 19 females, 4 immature, AM P22412.

Type locality. East of North Head, Sydney, New South Wales ( 33º49'S 151º18'E), in association with the sponge Polymastia cratica..

Description. Based on Myers & Moore, 1983:172, figs 1, 9, 10, 13 [east of Port Jackson, New South Wales].

Head. Rostrum absent or vestigial; Lateral cephalic lobes apically round, anteroventral margin shallowly excavate, scarcely recessed. Antenna 1 flagellum with 20 or less articles; accessory flagellum present and multiarticulate. Antenna 2 with few long setae. Labium with fine setae and stout setae. Mandible, palp article 3 longer than 2, posterior margin strongly falcate or straight or weakly falcate, mandible palp posterior margin with setae of two distinct lengths, long setae and an understory of much shorter regularly spaced setae.

Peraeon. Sternal spines absent. Gnathopod 1 enlarged in males only; coxa distinctly produced anterodistally, acute; basis slender, much less than half as broad as long, without a spine, anterior margin without stridulating ridges, posterodistal margin with setae sparse or absent, anterodistal margin with strong flange, with a weak distomedial lobe or absent; ischium anterior margin without flange, posterior margin with setae sparse or absent; merus greatly elongated, as long as or longer than elongate carpus, distally free, produced along posterior margin of carpus, recurved, apically acute or recurved, apically rounded, posterior margin with sparse setae or setae absent; carpus one and one third to one and one half length of propodus, anterior margin without stridulating ridges, with setae sparse or absent, anterior surface with no spine, without an oblique row of long setae on medial face, posterior margin without spines; propodus shorter than carpus, anterior margin weakly to moderately setiferous, posterior margin straight or evenly convex, palm absent; dactylus more than half length of propodus. Gnathopod 2 subchelate; basis anterodistal margin without flange, posterodistal margin without robust setae; with few setae along length of basis; carpus longer than propodus, anterior margin not lobate, moderately to sparsely setiferous; propodus moderately to sparsely setose, palm with robust seta(e) defining palm. Pereopod 6 basis not or weakly produced posterodistally. Pereopod 7 significantly less than 125% length of pereopod 6.

Pleon. Epimeron 3 posterodistal margin produced into a small spine. Uropod 1 biramous, rami rami subequal, peduncle much longer than broad, distoventral interramal spine shorter than peduncle. Uropod 2 peduncle without distoventral interramal spine or with vestigial spine. Uropod 3 biramous, rami subequal, inner ramus subequal with length of peduncle. Telson with distal fine setae only.

Habitat. In association with sponges Polymastia cratica and Teichonella labyrinthica.

Depth zones. Littoral.

Distribution. New South Wales: east of Port Jackson (Myers & Moore, 1983); Twofold Bay (Hutchings, et al., 1989).

Geographic areas. South-eastern Australia.

Peraeon. Gnathopod 1 coxa unproduced anterodistally; merus not greatly elongated, fused along its entire length with carpus, without posterodistal spine; carpus two thirds length of propodus; propodus longer than carpus, palm present, palm delimited from posterior margin, margin entire, palm defined by rounded or oblique corner or corner undefined, with robust seta defining palm; fitting palm. Gnathopod 2 carpus subequal with or shorter than propodus.

Cite this publication as: 'J.K. Lowry, P.B. Berents & R.T. Springthorpe (2001 onwards). Australian Amphipoda: Aoridae. Version 1: 2 October 2000. https://crustacea.net/'. Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993, 1995, 2000) should also be cited (see References).

Index