Sophrosyne integricauda, Lowry & Stoddart, 2010

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 : 14-16

Sophrosyne integricauda sp. nov.

( Figs 8 , 9 )

Type material. HOLOTYPE, female, 3.2 mm, MV J60739 , 44 km north-east of Cape Wickham , King Island, central Bass Strait, Australia (39°22.0'S 144°18.3'E), 60 m, coarse sand, grab, R. Wilson on RV Tangaroa , 23 November 1981, cruise 81- T-1 (stn BSS-203) . PARATYPES: female, 3.4 mm, AM P.46682, same data;?female, 2.4 mm, male, 2.7 mm, MV J7447, 25 km west-south-west of Cape Otway , western Bass Strait, Australia (38°55'S 143°25'E), 67 m, coarse sand, G.C.B. Poore on HMAS Kimbla , 8 October 1980, cruise 80- K-1 (stn BSS-53) .

Type locality. 44 km north-east of Cape Wickham , King Island, central Bass Strait, Australia (39°22.0'S 144°18.3'E), 60 m.

Etymology. The specific name refers to the entire telson of this species, an unusual character in the genus Sophrosyne .

Diagnostic description. Head lateral cephalic lobe small, broadly rounded; eyes oval. Antenna 1 peduncular article 1 short, length 1.4 x breadth; accessory flagellum short, 0.3 x primary flagellum, article 1 long, 3 x article 2; flagellum 6-articulate, without callynophore. Antenna 2 peduncular article 3 0.6 x article 4; flagellum 5-articulate. Mandible incisors with slightly convex margins; palp article 2 slender, 1.4 x article 3, with 1 submarginal posterodistal A2-seta, without D2-setae, article 3 length 4.6 x breadth, without D3- setae, with 4 apical E3-setae. Maxilla 1 outer plate with setal-teeth in a 2/0 arrangement. Maxilla 2 inner and outer plates broad. Maxilliped inner plate subovate, without apical nodular robust setae; outer plate submarginal setae long, simple; palp article 2 slender, length 2.5 x breadth, 1.1 x article 3, article 3 slender, length 2.8 x breadth, dactylus with unguis present. Gnathopod 1 basis length 1.7 x breadth, anterior margin without setae; ischium length 1.1 x breadth; merus, posterior margin lined with long slender setae; carpus length 0.5 x propodus; propodus length 1.7 x breadth, posterior margin slightly concave, without 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 3.3 x breadth, posterior margin straight; propodus subrectangular, short, length 1.8 x breadth; palm transverse, with straight margin, with minute robust setae. Pereopod 3 merus not expanded anteriorly. Pereopod 4 merus weakly expanded anteriorly. Pereopod 5 basis moderately expanded posteriorly; merus broadly 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 not expanded posteriorly; propodus without setae along anterior margin. Epimeron 3 posterior margin with weak spine above rounded posteroventral corner. Urosomite 1 with rounded boss, without lateral flange. Uropod 1 outer ramus slightly longer than inner ramus; outer ramus with 1 dorsal robust seta; inner ramus without dorsal robust setae. Uropod 2 rami subequal in length; rami without robust setae. Uropod 3 peduncle length 0.9 x breadth; rami inner ramus shorter than. Telson shorter than broad, length 0.9 x breadth, entire, distal margin rounded, with 2 apical slender setae.

Male (sexually dimorphic characters). Antenna 1 with strong 1-field callynophore.

Remarks. Sophrosyne integricauda differs from all other species of Sophrosyne in the very reduced tooth on the posterodistal corner of epimeron 3 and in the entire telson.

Distribution. Bass Strait, south-eastern Australia, in 60–67 m depth.

Figures

FIGURE 8. Sophrosyne integricauda sp. nov., holotype female, 3.2 mm, MV J60739, Cape Wickham, King Island, Bass Strait, Australia. Scales for mouthparts represent 0.05 mm, remainder represent 0.1 mm.

FIGURE 9. Sophrosyne integricauda sp. nov., holotype female, 3.2 mm, MV J60739, Cape Wickham, King Island, Bass Strait, Australia. Scales for U1–3 and T represent 0.01 mm, remainder represent 0.2 mm.