Pseudambasia acuticaudata (Ledoyer, 1984)

Kilgallen, N. M. & Lowry, J. K., 2013, The lysianassid genus Pseudambasia in Australian waters (Crustacea, Amphipoda, Lysianassidae, Lysianassinae), Zootaxa 3710 (4), pp. 301-321 : 302-303

Pseudambasia acuticaudata (Ledoyer, 1984)

Parambasia acuticaudata Ledoyer, 1984: 84 , fig. 41.—Barnard & Karaman, 1991: 514.—Lowry & Stoddart, 1994: 182.

Pseudambasia acuticaudata .—Lowry & Stoddart, 1995: 113, figs 8, 9.—Lowry & Stoddart, 2009: 565, figs 3, 4, pl. 4C.

Material examined. 4 specimens, AM P.68809, cove south of resort, Orpheus Island, Queensland, Australia (18°37'S 146°30'E), rubble substrate, 1–2 m, J.D. Thomas, 12 February 1989. 1 specimen, AM P.68810, same locality information as above except coral rubble, mostly Acropora .

Diagnostic description. Head lateral cephalic lobe broadly rounded; eyes oval. Antenna 1 peduncular article 1 short, length 1.4 × breadth, without dorsal lobe; peduncular article 2 long, 0.5 × article 1; peduncular article 3 long, 0.4 × article 1; accessory flagellum short, 0.3 × primary flagellum, 2 -articulate, article 1 long, subequal in length to article 2; primary flagellum 7-articulate, without callynophore, flagellum without aesthetascs. Antenna 2 flagellum 6-articulate. Mandible accessory setal row with 3 simple setae; molar reduced, represented by finely setose triangular flap; palp attached extremely proximally; article 1 long, length 2.2 × breadth; article 3 falcate, not apically bifurcate. Maxilla 1 inner plate without well-developed setae; outer plate broad with 11 setal teeth, setal teeth of outer row with cusps in 1 row; palp 2-articulate, with serrate apical margin. Maxilla 2 inner and outer plates broad; inner plate length 0.6 × outer plate. Labium outer lobe with distolateral stylets. Maxilliped inner plate with long apical robust seta.

Gnathopod 1 subchelate; coxa anterior margin slightly concave, anteroventral corner rounded, posterior margin straight; carpus short, length 1.4 × breadth, shorter than (0.9 ×) propodus; propodus subtriangular, length 1.7 × breadth, palm extremely acute, margin straight, rugose. Gnathopod 2 minutely subchelate; carpus long, length 3.3 × breadth, palm convex. Pereopod 5 coxa equilobate. Pereopod 6 coxa not lobate posteriorly; basis posterodistal corner produced beyond ischium, ventrally rounded. Pereopod 7 basis expanded posteriorly, posterodistal margin rounded, posterodistal corner produced, forming lobe produced halfway along merus; merus moderately expanded posteriorly.

Epimeron 3 posteroventral corner minutely notched. Uropod 1 outer ramus slightly longer than inner ramus. Uropod 2 outer ramus slightly longer than inner ramus; inner ramus with moderate constriction. Uropod 3 peduncle short, with dorsolateral flange; rami slender, outer ramus shorter than inner ramus. Telson longer than broad, length 1.2 × breadth, lateral margins converging distally, apical margin subacute.

Distribution. Lizard Island (Lowry & Stoddart 2009) and Orpheus Island (this publication), Great Barrier Reef, Australia; Rurutu, Austral Isles, French Polynesia (Lowry & Stoddart 1994); Îlot Maître, New Caledonia (Ledoyer 1984); Madang Lagoon, Papua New Guinea (Lowry & Stoddart 1995).