Sophrosyne murrayi Stebbing, 1888

Lowry, J. K. & Stoddart, H. E., 2010, Sophrosynidae, a new family in the Lysianassoidea (Crustacea: Amphipoda) with a revision of the genus Sophrosyne, Zootaxa 2370 (1), pp. 1-35 : 23-25

Sophrosyne murrayi Stebbing, 1888

( Fig. 13 )

Sophrosyne murrayi Stebbing, 1888: 652 , pl. 15. — Della Valle, 1893: 795, pl. 60, fig. 38. — Stebbing, 1906: 21. —J.L. Barnard, 1958: 99. — Thurston & Allen, 1969: 368. — Lowry & Bullock, 1976: 105. — De Broyer, 1977: 331. — Barnard & Karaman, 1991: 533. — De Broyer & Jazdzewski, 1993: 75. — De Broyer et al., 2007: 159.

Material examined. HOLOTYPE, female, approx. 13 mm, BMNH 1889:5:15:16, off Christmas Harbour , Kerguelen Islands , Southern Ocean (approx. 48°40'S 69°03'E), unknown depth but less than 274 m, Challenger Collection. 1 female, ovigerous, 12.5 mm; 1 female with non-setose oostegites, 12.0 mm; MV J38221 , Amery Depression , close to Amery Ice Shelf, Antarctica (68°56.69'S 73°36.78'E to 68°54.82'S 73°37.53'E), 786–791 m, epibenthic sled, M. O'Loughlin on RSV Aurora Australis , 17 February 1993 (stn AA93-157). 1 female with setose oostegites, 12.2 mm, MV J38222 , eastern Prydz Bay, off Larsemann Hills, Antarctica (68°54.88'S 76°37.03'E to 68°54.82'S 76°37.71'E), 667–716 m, epibenthic sled, M. O'Loughlin on RSV Aurora Australis , 18 February 1993 (stn AA93-158).

Type locality. Off Christmas Harbour , Kerguelen Islands, Southern Ocean (approx. 48°40'S 69°03'E) .

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 long, 0.6 x primary flagellum, article 1 long, 2.3 x article 2; flagellum 7+-articulate (broken), with weak 1-field callynophore. Antenna 2 peduncular article 3 0.53 x article 4; flagellum 9-articulate. Mandible incisors with slightly convex margins; palp article 2 slender, 1.1 x article 3, with 3 distal A2-setae and 2 submarginal posterodistal A2-setae, without D2-setae, article 3 length 5.3 x breadth, with or without D3-setae [ Stebbing (1888, pl.15) drew 4 D3- setae but none were visible on the slide we examined] and 5 apical E3-setae. Maxilla 1 outer plate with setal-teeth in a 2/4 arrangement. Maxilliped inner plate subrectangular, without apical nodular robust setae; outer plate submarginal setae absent; palp article 2 slender, length 2.2 x breadth, 1.2 x article 3, article 3 slender, length 2.3 x breadth, dactylus with unguis absent. Gnathopod 1 basis length 1.6 x breadth, anterior margin with slender setae; ischium length 0.8 x breadth; merus, posterior margin lined with long slender setae; carpus length 0.6 x propodus; propodus length 1.7 x breadth, posterior margin slightly concave, with robust setae and simple, slender setae, palm margin sinusoidal, posterodistal corner with produced subacute spine bearing vestigial seta. Gnathopod 2 grossly subchelate in female, [not known for male]; ischium length 2.8 x breadth; carpus long, length 2.1 x breadth, posterior margin broadly lobate; propodus subquadrate, short, length 1.3 x breadth; palm slightly acute, with large, concave, rugose margin. Pereopod 3 merus weakly expanded anteriorly. Pereopod 4 merus expanded anterodistally along carpus. Pereopod 5 basis greatly 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 subquadrate posteroventral corner. Urosomite 1 with anterodorsal notch and rounded boss, with lateral flange. Uropod 1 outer ramus slightly longer than inner ramus; outer ramus with 5 dorsal robust setae; inner ramus with 3 dorsal robust setae. Uropod 2 rami subequal in length; outer ramus with robust setae. Uropod 3 peduncle length 1.5 x breadth; inner ramus shorter than outer ramus. Telson longer than broad, length 1.1 x breadth, moderately cleft (60%), distal margins rounded, with1apical slender setae on each lobe.

Remarks. Sophrosyne murrayi shares with S. rodondo a lack of D2- and D3-setae on the mandibular palp, a slender maxillipedal palp article 2, an angled posteroventral corner with strong upturned tooth on epimeron 3 and a moderately cleft telson. Sophrosyne murrayi differs from S. rodondo in the setal-tooth arrangement on the outer plate of maxilla 1 (2/ 4 in S. murrayi and 2/ 5 in S. rodondo ), but most noticeably in gnathopod 2 which is grossly subchelate in S. murrayi and minutely subchelate in S. rodondo .

Distribution. Kerguelen Island, Southern Ocean; Amery Depression and Prydz Bay, Antarctica; 667–791 m depth.

Figures

FIGURE 13. Sophrosyne murrayi Stebbing, holotype female, approx. 13 mm, BMNH 1889:5:15:16, off Christmas Harbour, Kerguelen Islands, Southern Ocean. Whole animal and MX1 after Stebbing, 1888. Scales for G1, G2, P5, P7 represent 0.5 mm, remainder represent 0.2 mm.