Tryphosella wangaratta, Lowry & Stoddart, 2011

Lowry, J. K. & Stoddart, H. E., 2011, The tryphosine genera Photosella gen. nov. and Tryphosella Bonnier, 1893 (Crustacea: Amphipoda: Lysianassoidea: Lysianassidae: Tryphosinae) in Australian waters 2956, Zootaxa 2956 (1), pp. 1-76 : 70-73

Tryphosella wangaratta sp. nov.

( Figs 50–52 )

Type material. HOLOTYPE, male, 5.2 mm, MV J62291 , Crib Point , Western Port , Victoria, Australia, 38°21.15’S 145°14.44’E, 12 m, sand, Smith-McIntyre grab, 25 February 1965, Marine Studies Group , Fisheries and Wildlife Department , Ministry for Conservation, Victoria, CPBS stn 31E . PARATYPES: 1 female, with setose oostegites, 5.0 mm, MV J3509 , Crib Point , Western Port, Victoria, Australia, 38°20.25’S 145°14.69’E, 11 m, sand, Smith-McIntyre grab, 10 March 1965, Marine Studies Group, Fisheries and Wildlife Department, Ministry for Conservation, Victoria, CPBS stn 25N ; 1 female, MV J3503 , same locality and collector, 38°19.98’S 145°15.13’E, 2 m, mud and Zostera , Smith-McIntyre grab, 16 March 1965, CPBS stn 12N ; 1 female and 1 immature, MV J3506 , same locality and collector, 38°20.60’S 145°13.46’E, 13 m, shelly sand, Smith-McIntyre grab, 18 March 1965, CPBS stn 22N ; 1 male, 1 ovigerous female and 2 immatures, MV J3508 , same locality and collector, 38°20.67’S 145°14.74’E, 9 m, sand, Smith- McIntyre grab, 4 March 1965, CPBS stn 24N ; 1 female and 1 immature, MV J3514 , same locality and collector, 38°20.83’S 145°13.49’E, 13 m, sandy gravel, Smith-McIntyre grab, 23 March 1965, CPBS stn 32N.

Type locality. Crib Point , Western Port, Victoria, Australia, 38°21.15’S 145°14.44’E, 12 m depth .

Etymology. Named for the rural city of Wangaratta in north-eastern Victoria.

Diagnostic description. Head lateral cephalic lobe rounded, apically rounded; eyes apparently absent. 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 long; articles 4 and 5 not enlarged; flagellum short, calceoli absent. Epistome/Upper lip separate; epistome produced beyond upper lip, narrowly rounded; upper lip slightly produced, straight. Mandible molar with asymmetrically reduced column, proximally setose, distally triturating; palp attached about midway, article 3 with proximal A3-seta. Maxilla 1 outer plate setal-tooth 7, left and right asymmetrical, left cuspidate along most of sinusoidal inner margin, right cuspidate along most of weakly sinusoidal inner margin; palp distal margin with apical robust setae. Maxilliped basis without recurved hook; outer plate with 1 short apical robust seta.

Gnathopod 1 subchelate; coxa medium length (length 1.7 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 moderately acute, entire, straight. Gnathopod 2 palm moderately obtuse. Pereopod 4 coxa without distinct lateral ridge, with a well-developed posteroventral lobe. Pereopod 5 coxa without distinct lateral ridge, without umbo; basis longer than broad, without photophore, not posteroproximally excavate, posterior margin weakly serrate, posterior margin with mid-central spine, without posteroventral lobe or spine. 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 acutely produced. Urosomite 1 not projecting over urosomite 2, with deep notch and subtriangular, subacute boss. Uropods 1 and 2 outer rami without stout striated robust setae. Uropod 2 inner ramus without constriction. Uropod 3 peduncle without dorsolateral flange, with 1 short apicomedial robust seta; 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 subtriangular. Antenna 1 calceoli present, small. Antenna 2 peduncular articles 4 and 5 enlarged; flagellum long, calceoli present. Epistome/Upper lip epistome produced equally with upper lip. Gnathopod 1 simple; propodus margins tapering distally, palm absent. Urosomite 1 with wedge-shaped boss, obliquely truncated apically. Uropod 3 with plumose setae on both rami.

Remarks. Tryphosella wangaratta belongs to the group of Australian species ( T. betka , T. martrudan , T. toowoomba and T. wangaratta ) in which the male gnathopod 1 is simple. See Remarks for each of these species.

Tryphosella wangaratta is only known from shallow-water in Western Port. It has never been taken in traps.

Distribution. Western Port, Victoria, Australia; 2–14 m depth.

Figures

FIGURE 50. Tryphosella wangaratta sp. nov. Holotype, male, 5.2 mm, MV J62291; paratype, female, 5.0 mm, MV J3509; Crib Point, Western Port, Victoria. Scales represent 0.1 mm.

FIGURE 51. Tryphosella wangaratta sp. nov. Holotype, male, 5.2 mm, MV J62291; paratype, female, 5.0 mm, MV J3509; Crib Point, Western Port, Victoria. Scales represent 0.2 mm.

FIGURE 52. Tryphosella wangaratta sp. nov. Holotype, male, 5.2 mm, MV J62291; paratype, female, 5.0 mm, MV J3509; Crib Point, Western Port, Victoria. Scales represent 0.2 mm.