Australian Amphipoda: Aoridae

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

Bemlos tridentatus Myers, 1988b: 289, figs 20�21.

Type material. HOLOTYPE: male, 2.8 mm, AM P37426. PARATYPES: 2 females, AM P37427; 1 female, AM P38611.

Type locality.Reef off North Point, Lizard Island, Queensland, coral rubble at base of cliff, 18.5 m depth.

Description. Based on Myers, 1988: 289, figs 20�21 [Lizard Island].

Head. Rostrum absent or vestigial; Lateral cephalic lobes apically truncate, 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. Maxilla 1 inner plate with 1 long pectinate apical seta. Maxilliped basis without strong flange on anterior margin. Mandible, palp article 3 longer than 2, posterior margin widest medially, mandible palp posterior margin setae of more than two distinct lengths.

Peraeon. Sternal spines present, on other pereonites, apically acute or apically rounded. Gnathopod 1 enlarged in males only; coxa distinctly produced anterodistally, sub-acute, or distinctly produced anterodistally, acute; basis robust, half or more 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 not greatly elongated, fused along its entire length with carpus, posterior margin with sparse setae or setae absent, without posterodistal spine; 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 with stout spine or spines, three or more spines, proximal the larger; propodus shorter than carpus, anterior margin weakly to moderately setiferous, posterior margin straight or evenly convex, palm present, palm delimited from posterior margin, margin entire, palm defined by strong posterodistal spine, with robust seta defining palm, without spine near base of dactylus; dactylus more than half length of propodus, significantly overlapping palm. Gnathopod 2 subchelate; basis anterodistal margin with flange, posterodistal margin without robust setae; with few setae along length of basis; carpus subequal with or shorter 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 greater than 125% length of pereopod 6.

Pleon. Epimeron 3 posterodistal margin rounded. Uropod 1 biramous, rami rami subequal, peduncle much longer than broad, distoventral interramal spine shorter than peduncle. Uropod 2 peduncle with distoventral interramal spine. Uropod 3 biramous, rami subequal, inner ramus one and one half times length of peduncle. Telson with distal fine setae only.

Habitat. Coral rubble.

Depth zones. Littoral (18.5 m depth).

Distribution. Queensland: Lizard Island, Great Barrier Reef (Myers, 1988b).

Geographic areas. North-eastern Australia.

Peraeon. Sternal spines absent. Gnathopod 1 basis slender, much less than half as broad as long; carpus subequal in length with propodus or one and one third to one and one half length of propodus, posterior margin without spines; propodus subequal in length to carpus or longer than carpus, palm defined by rounded or oblique corner. Gnathopod 2 basis anterodistal margin without flange.

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