Key to the world species of Eriopisella Chevreux, 1920

1. Epimeron 3 posterodistal margin rounded.................................................................. 2 - Epimeron 3 posterodistal margin with acute spine........................................................... 3 2. Coxa 1 anterodistal corner acute................................................ E. capensis (K.H. Barnard, 1916) - Coxa 1 anterodistal corner rounded................................................... E. pusilla Chevreux, 1920 3. Gnathopod 1 merus expanded............................................................................ 4 - Gnathopod 1 merus unexpanded.......................................................................... 5 4. Uropod 3 outer ramus article 2 about one tenth length of article 1............................ E. epimera Griffiths, 1974

- Uropod 3 outer ramus article 2 about one third length of article 1................................. E. moretoni sp. nov.

5. Antenna 1 accessory flagellum vestigial much less than length of article 1 of primary flagellum....................... 6

- Antenna 1 accessory flagellum with 1–2 small articles approaching length of article 1 of primary flagellum.............. 7

6. Coxa 1 anterodistal corner acute................................................ E. seychellensis (Chevreux, 1901)

- Coxa 1 anterodistal corner rounded............................................ E. paraupolu Ortiz & Lalana, 1997

7. Antenna 1 primary flagellum with 11–12 articles.......................................... E. chieregoi Ruffo, 1985

- Antenna 1 primary flagellum with 17–19 articles............................................................. 8

8. Mandible palp article 3 subequal with article 2. Uropod 2 rami shorter than peduncle, subequal in length...................................................................................... E. ruffoi Marti & Villora-Moreno, 1996

- Mandible palp article 3 longer than article 2. Uropod 2 inner ramus subequal with peduncle, outer ramus shorter than inner................................................................................. E. upolu J.L. Barnard, 1970