Schisturella Norman, 1900

Schisturella Norman, 1900: 208.― Gurjanova, 1951: 212.― Gurjanova 1962: 193.―J.L. Barnard, 1966: 70 (in part).―J.L. Barnard, 1967: 71 (in part).―J.L. Barnard, 1969: 299, 303, 304, 306, 309, 310, 312, 314 (keys), 361 (in part).― Barnard & Ingram, 1990: 29 (in part).― Barnard & Karaman, 1991: 526 (in part).

Type species. Tryphosa pulchra Hansen, 1888, monotypy.

Included species. Schisturella includes seven species: S. adversicola (K.H. Barnard, 1925); S. cocula J.L. Barnard, 1966; S. dorotheae (Hurley, 1963); S. hansgeorgi Larsen, 2007; S. pulchra (Hansen, 1888); S. rosa sp. nov.; S. spinirama Hendrycks & Conlan, 2003.

Diagnostic description. Antenna 1 flagellum article 1 with robust seta on distal margin; accessory flagellum forming cap. Antenna 2 flagellum articles 3–5 slender, or article 4 slightly swollen in male; articles 4–5 with brush setae on the anterior margin. Mandible incisor curved; molar with reduced column and convex triturating surface (button); palp attached midway to distally. Maxilla 1 ST-7 serrate along distomedial margin; ST-D slender, serrate along distomedial margin. Maxilliped outer plate multiple apical robust setae present. Gnathopod 1 subchelate; coxa vestigial; carpus subequal to or longer than propodus; propodus palm acute, straight or slightly concave. Pereopod 4 coxa with well-developed posteroventral lobe. Uropod 2 inner ramus constricted. Uropod 3 rami with plumose setae in adult male, present or absent in adult female. Telson moderately to deeply cleft.

Remarks. Based on the diagnostic characters presented here, there are three main morphological characters that distinguish Schisturella from Pseudonesimus: the long robust seta present distally on the first article of the antenna 1 flagellum (absent in Pseudonesimus); the gnathopod 1 carpus length, which is subequal to or longer than the propodus (shorter in Pseudonesimus) and the shape and orientation of the gnathopod 1 palm which is acute and straight or slightly concave (convex in Pseudonesimus).

Distribution. Arctic, Atlantic, and Pacific Oceans.