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 Author Horton, Tammy Author Thurston, Michael H. text Zootaxa 2015 3995 1 91 132 journal article 10.11646/zootaxa.3995.1.12 8d98ec7c-9eda-448b-a63c-cc951edec20d 1175-5326 233262 DC0AEC92-B7C7-4310-BB9D-F9BE6594A98A Key to the genera of Paracallisominae 1. Gnathopod 1, basis expanded (glandular?).................................................................. 2 - Gnathopod 1, basis ordinary............................................................................. 4 2. Maxilla 1, inner plate fully setose along medial margin........................................................ 3 - Maxilla 1, inner plate with only 1 pappose apical seta.............................................. Anisocallisoma 3. Maxilliped palp article 4 vestigial; posteroventral lobe of pereopod 4 coxa strongly narrowed, subacute.......... Tayabasa - Maxilliped palp article 4 well developed; posteroventral lobe of pereopod 4 coxa broad, subquadrate.......... Eucallisoma 4. Pereopods 3 to 7 or only pereopods 3 and 4 strongly prehensile................................................. 5 - Pereopods 3 to 7 not prehensile........................................................................... 6 5. Pereopods 3 and 4 prehensile; gnathopod 1 elongate, slender, longer than gnathopod 2; pereopods 3 and 4 carpus strongly com- pressed, shorter than wide; pereopod 5 basis subrectangular...................................... Scopelocheiropsis - Pereopods 3 to 7 prehensile; gnathopod 1 not elongate, robust, subequal to gnathopod 2; pereopods 3 and 4 carpus longer than wide; pereopod 5 basis suboval....................................................... Haptocallisoma gen. nov. 6. Coxae 1 and 2 tapering distally........................................................................... 7 - Coxae 1 and 2 subrectangular, not tapering distally........................................................... 8 7. Maxilla 1 palp 2-articulate, maxilliped palp article 4 well developed........................ Pseudocallisoma gen. nov. - Maxilla 1 palp 1-articulate, maxilliped palp article 4 absent........................................ Austrocallisoma 8. Pereopod 5 basis subcircular; gnathopod 1 propodus strongly tapering................................ Bathycallisoma - Pereopod 5 basis pyriform; gnathopod 1 propodus subrectangular.................................... Paracallisoma