Tryphosa Boeck, 1871

Tryphosa Boeck, 1871: 117 .― Stephensen, 1925: 101 (in part).

Orchomene .― Barnard & Karaman, 1991: 507 (in part).

Tryphosella .―J.L. Barnard, 1969: 365 (in part).

Type species. Anonyx nanus Krøyer, 1846a, by monotypy.

Included species. Tryphosa includes two species: T. crenata (Chevreux & Fage, 1925); T. nana (Krøyer, 1846a) .

Diagnostic description. Antenna 1 flagellum article 1 lacking robust seta on distal margin; accessory flagellum forming cap. Antenna 2 flagellum article 5 slender (with dense brush setae on the anterior margin). Mandibular incisor slightly curved; molar a reduced column with convex triturating surface (button); palp attached midway. Maxilla 1 ST-7 serrate along most of curved medial margin; ST-D slender, serrate along the entire curved medial margin. Maxilliped outer plate apical setae present. Gnathopod 1 subchelate; coxa large, nearly as long as coxa 2, not tapering; carpus slightly shorter than propodus; propodus palm slightly acute, straight. Pereopod 4 coxa with well developed posteroventral lobe. Uropod 2 inner ramus constricted. Uropod 3 rami with plumose setae in male and female; inner ramus broad, lanceolate. Telson deeply cleft.

Remarks. See d’Udekem d’Acoz & Havermans (2012) for a comprehensive summary of the historical taxonomic and nomenclatural treatment of Tryphosa .

Tryphosa is easily separated from Orchomenella, with which it has long been associated, by the constricted inner ramus on uropod 2.

Distribution. Northeast Atlantic, Mediterranean Sea, Adriatic Sea.