Australian Amphipoda: Aoridae

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

Archaeolembos philacanthus (Stebbing, 1888)

Autonoe philacantha Stebbing, 1888: 1082, pl. 110.

Lembos philacanthus. --Stebbing, 1906: 598, fig. 102. --Stebbing, 1910: 650. --Sheard, 1937: 26.

Archaeobemlos philacanthus Myers, 1988b: 267, figs 1�3.

Not Lembos philacanthus. --Chilton, 1921: 77, fig. 11a-c (Probably an undescribed species of Bemlos).

Type material. HOLOTYPE: male, BMNH

Type locality. Off East Moncoeur Island, Bass Strait, Tasmania (39�10�30�S 146�37�0�E) ("Challenger" Station 162).

Description. Based on Myers, 1988: 267, figs 1�3 [Bass Strait].

Head. Rostrum absent or vestigial; Lateral cephalic lobes apically truncate, anteroventral margin moderately excavate, moderately recessed. Antenna 1 flagellum with 21 or more articles; accessory flagellum present and multiarticulate. Antenna 2 with profuse 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 shorter than 2, posterior margin strongly 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 both sexes; coxa unproduced anterodistally, or distinctly produced anterodistally, sub-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 two thirds 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 longer than carpus, anterior-distal margin densely clothed in long setae, 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, fitting palm. 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 densely 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 inner ramus distinctly longer than outer, 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, outer ramus shorter than inner, inner ramus twice length of peduncle. Telson with distal fine setae only.

Habitat. On gravel, sand and mud bottoms in depths of 50 � 150m.

Depth zones. Continental shelf.

Remarks. Female not described.

Distribution. Queensland: Lady Elliot Island, Great Barrier Reef (Myers, 1988b). New South Wales: Off Port Hacking and Wattamoola (Stebbing, 1910). Tasmania: Off East Moncoeur Island, Bass Strait (Stebbing, 1888); Bass Strait (Myers, 1988b).

Geographic areas. South-eastern Australia, or Southern Australia.

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