Sophrosyne cantractia Lowry & Stoddart 2010, sp. nov.

Sophrosyne cantractia sp. nov.

(Figs 4, 5)

Type material. HOLOTYPE, female, ovigerous (2 eggs), 5.8 mm, MV J38218, western part of MacRobertson Shelf, Antarctica (66°55.51'S 62°32.72'E to 66°55.33'S 62°32.16'E), 113 m, epibenthic sled, M. O'Loughlin on RSV Aurora Australis, 11 February 1993 (stn AA93-124). PARATYPES: 1 specimen, 4.2 mm, MV J38219, western part of MacRobertson Shelf, Antarctica (66°53.69'S 63°06.34'E to 66°53.67'S 63°05.51'E), 367–439 m, epibenthic sled, M. O'Loughlin on RSV Aurora Australis, 11 February 1993 (stn AA93-125); 2 juveniles, MV J60736 and MV J60737, off Enderby Land, Antarctica, Southern Ocean (65°56.40'S 50°52.10'E), 386–400 m, shelly mud, silt and bryozoan shell, epibenthic sled, M. Norman on MS Nella Dan, 15 November 1985 (stn HRD 010).

Type locality. Western part of MacRobertson Shelf, Antarctica (66°55.51'S 62°32.72'E to 66°55.33'S 62°32.16'E), 113 m.

Etymology. The specific name is contrived as an anagram of the specific name of the neighbouring species, Sophrosyne antarctica.

Diagnostic description. Head lateral cephalic lobe small, narrowly rounded; eyes apparently absent. Antenna 1 peduncular article 1 short, length 1.3 x breadth; accessory flagellum medium length, 0.5 x primary flagellum, article 1 short, 1.3 x article 2; flagellum 7-articulate, without callynophore. Antenna 2 peduncular article 3 0.6 x article 4; flagellum 7-articulate. Mandible incisors with straight margins; palp article 2 slender, 1 x article 3, with 2 submarginal posterodistal A2-setae, D2-setae present, article 3 length 7 x breadth, without D3-setae, with 3 apical E3-setae. Maxilla 1 outer plate with setal-teeth in a 2/3 arrangement . Maxilla 2 inner plate narrow, outer plate broader; inner plate length 0.66 x outer plate. Maxilliped inner plate subrectangular, with 1 apical, nodular robust setae; outer plate submarginal setae long, simple; palp article 2 broad, length 1.8 x breadth, 1.1 x article 3, article 3 slender, length 2.6 x breadth, dactylus with unguis vestigial. Gnathopod 1 basis length 1.8 x breadth, anterior margin with slender setae; ischium length 1.1 x breadth; merus, posterior margin lined with long slender setae; carpus length 0.5 x propodus; propodus length 1.8 x breadth, posterior margin slightly concave, with robust setae and simple, slender setae, palm margin straight, posterodistal corner with produced subacute spine bearing vestigial seta. Gnathopod 2 minutely subchelate; ischium length 3 x breadth; carpus long, length 3.8 x breadth, posterior margin straight; propodus subrectangular, long, length 2.3 x breadth; palm transverse, with convex, serrate margin. Pereopod 3 merus not expanded anteriorly. Pereopod 4 merus weakly expanded anteriorly. Pereopod 5 basis moderately expanded posteriorly; merus moderately expanded posteriorly. Pereopod 6 coxa small, slightly lobate posteriorly; merus expanded posteriorly. Pereopod 7 basis posterior margin slightly rounded, minutely crenate, posteroventral margin straight, posteroventral lobe not extending beyond ischium; merus slightly expanded posteriorly; propodus with setae along anterior margin. Epimeron 3 posterior margin with strong upturned spine above rounded posteroventral corner . Urosomite 1 with anterodorsal notch and rounded boss, without lateral flange. Uropod 1 rami subequal in length; outer ramus with 2 dorsal robust setae; inner ramus with 1 dorsal robust seta. Uropod 2 rami subequal in length; outer ramus with robust setae. Uropod 3 peduncle length 1.4 x breadth; rami subequal in length. Telson longer than broad, length 1.3 x breadth, moderately cleft (53%), distal margins rounded, with 1 apical slender seta on each lobe.

Remarks. See remarks under S. californica.

Distribution. Off MacRobertson Shelf and Enderby Land, east Antarctica, in 113–439 m depth.