Schisturella rosa, Kilgallen & Lowry, 2014

Kilgallen, N. M. & Lowry, J. K., 2014, The Tryphosa group (Crustacea: Amphipoda: Lysianassoidea: Lysianassidae: Tryphosinae), Zootaxa 3768 (5), pp. 501-545 : 521-525

Schisturella rosa sp. nov.

( Figs 11–13 )

Types. Holotype, female, 19.0 mm, AM P.68993, from east of Broken Bay , New South Wales, Australia (33°34.8’S 152°4.8’E to 33°37.2’S 152°4.8’E) 1144 m, dredge, 10 December 1980, FRV Kapala stn K80-20-10 . Paratypes: 1 male, 21.5 mm, AM P.68995, from east of Broken Bay , New South Wales, Australia (33°40.2’S 152°6’E to 33°43.2’S 152°4.2’E) 1108 m, trawl, 19 December 1985, FRV Kapala stn K85-21-05 ; 1 specimen, 13.0 mm, AM P.68994, from east of Broken Bay , New South Wales, Australia (33°34.8’S 152°4.8’E to 33°37.2’S 152°4.8’E) 1144 m, dredge, 10 December 1980, FRV Kapala stn K80-20-10 ; 5 specimens, 12.4–19.8 mm, AM P.68992, from east of Broken Bay , New South Wales, Australia (33°37.2’S 152°4.2’E to 33°39’S 152°1.8’E) 896 m, dredge, 10 December 1980, R. T. Springthorpe, FRV Kapala stn K80-20-09 ; 5 specimens, 8.3–18.0 mm, AM P.68996, from east of Broken Bay , New South Wales, Australia (33°30’S 152°9’E to -33°33’S 152°10.8’E) 922 m, beam trawl, 12 February 1986, R. T. Springthorpe, FRV Kapala stn K86-01-08 .

Additional material examined. New South Wales: 86 specimens, AM P.43365, from north-east of Coffs Harbour (30°10.9’S 153°32.27’E) 1000 m, baited trap, Globigerina ooze, 08 September 1994 – 09 September 1994, J.K. Lowry & K. Dempsey, MV Carrie Ann stn NSW-1000 . 3 specimens, AM P.43421, from off Wollongong (34°32.4’S 151°22.8’E) 1000 m, Globigerina ooze, 27 March 1994, J.K. Lowry & K. Dempsey, MV Robin E stn NSW-954 . 35 specimens, AM P.43427, from off Wollongong (34°32.4’S 151°22.8’E) 1000 m, baited trap, 54.7% sand, 45.3% mud, 27 March 1994, J.K. Lowry & K. Dempsey, MV Robin E stn NSW-953 . 3 specimens, AM P.43436, from off Wollongong (34°32.4’S 151°22.8’E) 1000 m, baited trap, 28 March 1994 – 29 March 1994, J.K. Lowry & K. Dempsey, MV Robin E stn NSW-973 . 15 specimens, AM P.43445, from off Wollongong (34°32.4’S 151°22.8’E) 1000 m, 28 March 1994, J.K. Lowry & K. Dempsey, MV Robin E stn NSW-971 . 3 specimens, AM P.43453, from off Wollongong (34°32.4’S 151°22.8’E) 1000 m, baited trap, 28 March 1994, J.K. Lowry & K. Dempsey, MV Robin E stn NSW-972 . 51 specimens, AM P.44367, from off Wollongong (34°33.41’S 151°21.35’E) 1000 m, Baited Trap, Globigerina ooze, 6 May 1993 – 7 May 1993, P. Freewater & party, MV Robin E stn NSW-788 . 115 specimens, AM P.44374, from off Wollongong (34°33.41’S 151°21.35’E) 1000 m, baited trap, Globigerina ooze, 6 May 1993 – 7 May 1993, P. Freewater & party, MV Robin E stn NSW-789 . 1 specimen, AM P.44385, from off Wollongong (34°33.21’S 151°21.4’E) 1000 m, Globigerina ooze, 7 May 1993, P. Freewater & party, MV Robin E stn NSW-806 . 2 specimens, AM P.44392, from off Wollongong (34°33.21’S 151°21.4’E) 1000 m, Globigerina ooze, 7 May 1993, P. Freewater & party, MV Robin E stn NSW-808 . 153 specimens, AM P.48096, from north-east of Coffs Harbour (30°10.94’S 153°32.27’E) 963 m, baited trap, 11–12 August 1993, P.B. Berents, R. T. Springthorpe & W. Vader, MV Cheryl Lee stn NSW-862 . 151 specimens, AM P.48116, from north-east of Coffs Harbour (30°10.94’S 153°32.27’E) 963 m, baited trap, 11–12 August 1993, P.B. Berents, R. T. Springthorpe & W. Vader, MV Cheryl Lee stn NSW-863 . 282 specimens, AM P.49809, from north-east of Coffs Harbour (30°10.88’S 153°32.21’E) 1000 m, baited trap, 12–13 August 1993, P.B. Berents, R. T. Springthorpe & W. Vader, MV Cheryl Lee stn NSW-876 . 311 specimens, AM P.49826, from north-east of Coffs Harbour (30°10.88’S 153°32.21’E) 1000 m, baited trap, 12–13 August 1993, P.B. Berents, R. T. Springthorpe & W. Vader, MV Cheryl Lee stn NSW-877 . 6 specimens, AM P.50069, from north-east of Coffs Harbour (30°10.94’S 153°32.27’E) 1000 m, baited trap, 9–10 September 1994, J.K. Lowry & K. Dempsey, MV Carrie Ann stn NSW-1021 . 1 specimen, AM P.50084, from north-east of Coffs Harbour (30°10.94’S 153°32.27’E) 1000 m, 9 September 1994, J.K. Lowry & K. Dempsey, MV Carrie Ann stn NSW-1022 . 6 specimens, AM P.52659, from north-east of Coffs Harbour (30°10.88’S 153°32.21’E) 1000 m, baited trap, 12–13 August 1993, P.B. Berents, R. T. Springthorpe & W. Vader, MV Cheryl Lee stn NSW-876 . 32 specimens, AM P.56077, from north-east of Coffs Harbour (30°10.88’S 153°32.21’E) 1000 m, baited trap, 12–13 August 1993, P.B. Berents, R. T. Springthorpe & W. Vader, MV Cheryl Lee stn NSW-877 . 1 female, AM P.68991, from off Wollongong (34°32.4’S 151°22.8’E) 1000 m, baited trap, 27 March 1994, J.K. Lowry & K. Dempsey, MV Robin E stn NSW-953 .

Tasmania: 106 specimens, AM P.51312, from east of Fortescue Bay (43°8.96’S 148°15.36’E) 1000 m, baited trap, 8–9 April 1994, J.K. Lowry & K. Dempsey, MV Martrudan stn TAS-403. 10 specimens, AM P.51382, from east of Fortescue Bay (43°8.96’S 148°15.36’E) 1000 m, baited trap, 8–9 April 1994, J.K. Lowry & K. Dempsey, MV Martrudan stn TAS-422. 46 specimens, AM P.51389, from east of Fortescue Bay (43°8.96’S 148°15.36’E) 1000 m, baited trap, 9–10 April 1994, J.K. Lowry & K. Dempsey, MV Martrudan stn TAS-421. 113 specimens, AM P.57978, from east of Fortescue Bay (43°8.96’S 148°15.36’E) 1000 m, baited trap, 8–9 April 1994, J.K. Lowry & K. Dempsey, MV Martrudan stn TAS-423. 666 specimens, AM P.74783, from 76.8 km south-south-east of South East Cape, Main Pedra Hill (44°15.6’S 147°7.8’E) 1312 m, baited trap, 21–24 January 1997, CSIRO party, FRV Southern Surveyor stn SS01/97/08 .

Type locality. East of Broken Bay , New South Wales, Australia (33°34.8’S 152°4.8’E to 33°37.2’S 152°4.8’E), 1144 m depth .

Etymology. The specific epithet ‘rosa’ is a reference to the deep pink colour of the eyes in this species.

Description. Based on holotype female, 19.0 mm, AM P.68993. Head lateral cephalic lobe subtriangular, apically acute; eyes reinform, bright red. Antenna 1 accessory flagellum forming cap partially covering callynophore, 8-articulate; primary flagellum with strong 2-field callynophore, long robust seta present on article 1; calceoli absent. Antenna 2 peduncular article 3 short; articles 3 to 5 not enlarged, with very weak brush setae; flagellum short, calceoli absent. Labrum, epistome and upper lip separate; epistome less produced than upper lip, straight; upper lip produced, subacute apically. Mandible molar with reduced column and convex fully triturating surface; palp attached distally, article 3 with 1 proximal A3-setae. Maxilla 1 outer plate setal-tooth 7 present, cuspidate distally; palp distal margin with apical robust setae. Maxilliped outer plate with 4 slender apical robust setae.

Pereonites 1–7 dorsally smooth. Gnathopod 1 subchelate; coxa small, reduced, significantly shorter than coxa 2, subquadrate; basis moderately setose along anterior margin; carpus long, longer than propodus, without posterior lobe; propodus small, margins slightly tapering distally, sparsely setose along posterior margin, palm moderately acute, entire, concave. Gnathopod 2 subchelate, propodus palm transverse. Pereopod 5 basis longer than broad, not posteroproximally excavate, posterior margin weakly serrate. Pereopod 7 basis posterodistally produced, not reaching merus.

Pleonite 3 without mid-dorsal carina, not produced dorsodistally, posterodorsal margin not produced. Epimeron 3 posterior margin smooth, posteroventral corner acutely produced forming weak spine. Urosomite 1 not projecting over urosomite 2, dorsally straight. Uropod 2 inner ramus with constriction. Uropod 3 inner and outer rami well developed, outer ramus article 2 long, without plumose setae on rami. Telson moderately to deeply cleft, with 2–3 dorsal robust setae per lobe and 1 apical robust setae on each lobe.

Sexually dimorphic characters. Based on paratype, male, 21.5 mm, AM P.68995. Antenna 1 and 2 with calceoli, antenna 2 peduncle article 4 slightly swollen, articles 4 and 5 with brush setae. Uropod 3 rami with plumose setae.

Remarks. In contrast to the female holotype, which has only very weak brush setae on the peduncle of antenna 2 and a complete absence of plumose setae on uropod 3, a very large female (AM P.68991) from off Wollongong has well-developed brush setae and some sparse plumose setae on the rami of uropod 3, suggesting that these characters only develop in more mature females.

Schisturella rosa sp. nov. appears to be morphologically most similar to Schisturella cocula . These species may be separated by the second gnathopod, which is subchelate with a transverse palm in S. rosa but minutely chelate with a distinctly obtuse palm in S. cocula .

Depth range. 896–1312 m (this study).

Distribution. Tasman Sea. Continental slope of east Australia from Coffs Harbour, New South Wales to South East Cape, Tasmania (this study).

Figures

FIGURE 11. Schisturella rosa sp. nov., holotype, female, 19.0 mm, AM P.68993, from east of Broken Bay, New South Wales, Australia. Scale bars: 0.1 mm.

FIGURE 12. Schisturella rosa sp. nov., female, 19.0 mm, AM P.68993, from east of Broken Bay, New South Wales, Australia. Scale bars: 0.1 mm.

FIGURE 13. Schisturella rosa sp. nov., female, 19.0 mm, AM P.68993, from east of Broken Bay, New South Wales, Australia. Scale bars: 0.2 mm.