Paracallisoma Chevreux, 1903

Horton, Tammy & Thurston, Michael H., 2015, A revision of the genus Paracallisoma Chevreux, 1903 (Crustacea: Amphipoda: Scopelocheiridae: Paracallisominae) with a redescription of the type species of the genus Paracallisoma and the description of two new genera and two new species from the Atlantic Ocean, Zootaxa 3995 (1), pp. 91-132 : 93

Paracallisoma Chevreux, 1903 sensu stricto

Paracallisoma Chevreux 1903: 84 .— Schellenberg 1926a: 257.— Chevreux 1935: 39.— Gurjanova 1962: 308.— Hurley 1963: 60.— J.L. Barnard 1969: 305 (key), 354.— Barnard & Karaman 1991: 454 (key), 510.— Hendrycks & Conlan 2003: 2322.

Type species. Paracallisoma alberti Chevreux, 1903 , original designation.

Diagnosis. Eyes absent, or present, lacking ommatidea, red-pigmented, pigment lost in alcohol. Mandible, left lacinia mobilis a stemmed, distally asymmetrically expanded, serrate blade; incisor ordinary, molar an acute conical structure; palp attached level with molar. Lower lip, lobes separate, sub-triangular. Maxilla 1, outer plate broad with eleven setal teeth in simple 7/4 arrangement, inner plate strongly setose medially, palp 2-articulate, article 2 large, slender, rectangular. Maxilla 2 inner and outer plates subequal in width, inner plate slightly shorter than or subequal in length to outer plate. Maxilliped, inner plate almost straight apically, palp strongly exceeding outer plate, dactyl well developed. Gnathopod 1 simple, coxa large, subrectangular (not tapered), slightly shorter than coxa 2; basis linear; ischium long; propodus longer than or subequal to carpus; dactyl vestigial, shrouded in setae. Gnathopod 2 subchelate, coxa large, subrectangular (not tapered), propodus shorter than carpus, ordinary. Pereopods 3–7 robust but not prehensile. Pereopods 3 and 4, carpus longer than wide. Pereopod 5 basis weakly expanded proximally, widening distally with strong posterodistal lobe. Uropod 1 peduncle normal, rami 0.7 x peduncle. Telson with apices incised.

Remarks. The species in this genus can be linked by the possession of a pyriform pereopod 5 basis and robust, but not prehensile, pereopods 3–7. The distolateral, subapical notch with robust seta on each telson lobe is typical.

Included species. Paracallisoma sensu stricto currently includes three species: P. alberti Chevreux, 1903 ; P. idioxenos sp. nov.; P. zivianii ( Kilgallen & Lowry, 2015) .