Tasmanosa tasman, Lowry & Kilgallen, 2014

Lowry, J. K. & Kilgallen, N. M., 2014, New tryphosine amphipods from Australian waters (Crustacea, Amphipoda, Lysianassoidea, Lysianassidae, Tryphosinae), Zootaxa 3844 (1), pp. 1-64 : 44-45

Tasmanosa tasman sp. nov.

( Figs 32–34 )

Types. Holotype, ovigerous female, 10.2 mm, AM P.71642, east of Fortescue Bay , Tasmania, Australia (43°8.96’S 148º15.36’E), 1000 m, baited trap, 8 April 1994 – 09 April 1994, J.K. Lowry & K. Dempsey, MV Martrudan stn TAS-423 . Paratypes: 5 specimens, 7.5–8.0 mm, AM P.51093, and 2 specimens, 4.8–8.5 mm, AM P.52149, both with same collection details as holotype ; 1 male, 10.0 mm, AM P.71643, and 40 specimens, 7.0– 15.5 mm, AM P.71644, 76.8 km south-southeast of South East Cape , Main Pedra Hill, Tasmania, Australia (44º15.6’S 147º07.8’E), 1312 m, baited trap, 21 January 1997 – 24 January 1997, CSIRO party, FRV Southern Surveyor stn SS01/97/08 .

Additional material examined. 1 specimen, AM P.73699, Tasman Sea , south-southeast of South East Cape, Tasmania, Australia (44º23.4’S 147º16.2’E), 1942 m, baited trap, 31 January 1997 – 31 January 1997, CSIRO party, FRV Southern Surveyor stn SS01/97/65 ; 307 specimens, AM P.78689, Tasman Sea , 76.8 km south-south-east of South East Cape, Main Pedra Hill, Tasmania, Australia (44º15.6’S 147º07.8’E), 1312 m, baited trap, 21 January 1997 – 24 January 1997, CSIRO party, FRV Southern Surveyor stn SS01/97/08; many specimens, AM P.73700, Tasman Sea , 76.8 km south-southeast of South East Cape , Main Pedra Hill, Tasmania, Australia (44º15.6’S 147º07.8’E), 1312 m, baited trap, 21 January 1997 – 24 January 1997, CSIRO party, FRV Southern Surveyor stn SS01/97/08 .

Type Locality. East of Fortescue Bay , Tasmania, Australia (43°8.96’S 148º15.36’E), 1000 m depth .

Etymology. Named for the steamship Tasman lost near Hippolyte Rocks, Tasmania in November 1883; used as a noun in apposition.

Description. Based on holotype, female, 10.2 mm AM P.71642. Head lateral cephalic lobe subtriangular, apically acute. Antenna 1 accessory flagellum not forming operculum; primary flagellum with strong 2-field callynophore, robust setae present on proximal articles; calceoli absent. Antenna 2 peduncular article 3 short; articles 3 to 5 not enlarged; flagellum short, calceoli absent. Labrum, epistome and upper lip separate; epistome produced equally with upper lip, broadly rounded; upper lip not produced. Mandible molar with asymmetrically reduced column, proximally setose, distally triturating. Maxilla 1 outer plate setal-tooth 7 present, left and right symmetrical, cuspidate distally; palp distal margin with apical robust setae. Maxilliped outer plate with 4 long, slender apical robust setae.

Pereonites 1–7 dorsally smooth. Gnathopod 1 subchelate; coxa large, about as long as coxa 2, slightly tapering distally; basis densely setose along anterior margin; ischium short; carpus short, shorter than propodus, without posterior lobe; propodus densely setose along posterior margin, palm transverse, straight, striated. Gnathopod 2 minutely subchelate; propodus palm transverse to slightly obtuse. Pereopod 5 coxa producing anterior lobe; basis longer than broad, not posteroproximally excavate, posterior margin weakly serrate. Pereopod 7 basis posterodistally produced, reaching merus.

Pleonite 3 without mid-dorsal carina, not produced dorsodistally, posterodorsal margin not produced. Epimeron 3 posterior margin smooth, rounded, posteroventral corner narrowly rounded. Urosomite 1 dorsally straight, obliquely truncated apically . Uropod 2 inner ramus without constriction. Uropod 3 inner and outer rami well developed, outer ramus article 2 short, without plumose setae on rami. Telson deeply cleft, longer than wide, with 1 dorsal robust seta and 1 apical robust setae on each lobe.

Sexually dimorphic characters. Based on paratype, male, 10.0 mm, AM P.71643. Antenna 1 and 2 with calceoli.

Remarks. See remarks under Tasmanosa toogooloo sp. nov.

Depth range. 1000–1942 m.

Distribution. Australia. Tasmania.

Figures

FIGURE 32. Tasmanosa tasman sp. nov., habitus, holotype, female, 10.2 mm, AM P. 71642, from east of Fortescue Bay, Tasmania, Australia.

FIGURE 33. Tasmanosa tasman sp. nov., holotype, female, 10.2 mm, AM P.71642, from east of Fortescue Bay, Tasmania, Australia; paratype, male, 10.0 mm, AM P.71643, south-southeast of South East Cape, Main Pedra Hill, Tasmania, Australia. Scale: antennae, 0.2 mm; mouthparts, 0.1 mm.

FIGURE 34. Tasmanosa tasman sp. nov., holotype, female, 10.2 mm, AM P.71642, from east of Fortescue Bay, Tasmania, Australia. Scale: gnathopods, pereopods, 0.5 mm; uropods, telson, 0.1 mm.