Tryphosella orana J. L. Barnard 1972

Tryphosella orana J.L. Barnard, 1972

Tryphosella orana J.L. Barnard, 1972: 276, figs 164, 165. — Jones, 1986: 14. — Sergeev et al., 1988: 102 (table 1). — Barnard & Karaman, 1991: 537. — Lowry & Stoddart, 2003: 171.

Type locality. Middleton Beach, Albany, Western Australia, [approx. 35°00’S 117°52’E], intertidal.

Material examined. Western Australia: 9 specimens, AM P.70530, Vancouver Peninsular, near Mistaken Island, King George Sound, 35°04'S 117°56'E, 6 m, sea grass with bryozoan or fine pink alga, 13 December 1983, R. T. Springthorpe, stn WA-120; 1 male, AM P.70531, off Possession Point, King George Sound, 35°02.5'S 117°55'E, 10 m, sand and detritus from bases of sea grass, 14 December 1983, R. T. Springthorpe & J.K. Lowry, stn WA-131; 2 ovigerous females, AM P.70532, 2 km south-east of South Point, Two Peoples Bay, 34°58'S 118°12'E, 14 m, Caulerpa bases and sand from fine sand bottom, 16 December 1983, J.K. Lowry, stn WA-178.

Diagnostic description. Head lateral cephalic lobe rounded, apically rounded; eyes lageniform (but fading in alcohol). Antenna 1 peduncular articles 1 and 2 without anterodistal lobe; accessory flagellum not forming cap, terminal article not offset; flagellum with strong 2-field callynophore, robust setae absent from proximal articles; calceoli absent. Antenna 2 peduncular article 3 short; articles 4 and 5 not enlarged; flagellum short, calceoli absent. Epistome/Upper lip separate; epistome produced beyond upper lip, broadly rounded; upper lip slightly produced, rounded apically Mandible molar with asymmetrically reduced column, proximally setose, distally triturating; article 3 with proximal A3-seta; palp distal margin with apical robust setae. Maxilliped outer plate with 2 short apical robust setae.

Gnathopod 1 subchelate; coxa small (length 1.1 x breadth), subtriangular, tapering distally; basis sparsely setose along anterior margin; ischium short; carpus long, subequal in length to propodus, without posterior lobe; propodus small, margins subparallel, palm slightly acute, entire, straight. Gnathopod 2 propodus palm slightly obtuse . Pereopod 4 coxa without distinct lateral ridge, with a well-developed posteroventral lobe. Pereopod 5 coxa without distinct lateral ridge, without umbo; basis about as long as broad, not posteroproximally excavate, posterior margin weakly serrate. Pereopod 7 basis posterodistally produced less than halfway along merus, not posterodistally excavate.

Pleonites 1–3 without mid-dorsal carina, not produced dorsodistally. Epimeron 3 posterior margin smooth, posteroventral corner narrowly rounded. Urosomite 1 not projecting over urosomite 2, with anterodorsal notch and slightly rounded boss. Uropods 1 and 2 outer rami with distal stout striated robust setae. Uropod 2 inner ramus without constriction. Uropod 3 peduncle without dorsolateral flange, with 2 short apicomedial robust setae; inner and outer rami well developed, outer ramus article 2 short, without plumose setae on rami. Telson deeply cleft, with dorsal robust setae, with 1 apical robust seta on each lobe.

Male (sexually dimorphic characters). Head lateral cephalic lobe a semidome. Antenna 1 calceoli small. Antenna 2 peduncular articles 4 and 5 enlarged; flagellum long, calceoli present. Urosomite 1 with anterodorsal notch and rounded boss. Uropod 3 with 1 short apicomedial robust seta; with plumose setae on both rami.

Remarks. Tryphosella orana is one of the group of six Australian species with stout striated robust setae on the outer rami of uropods 1 and 2 (see Remarks under T. fortescue). Tryphosella orana is most similar to T. tathra – see Remarks under that species.

Distribution. Southern Western Australia, intertidal to 14 m depth.