Uroptychus

Baba, Keiji & Wicksten, Mary K., 2017, Uroptychus nitidus (A. Milne-Edwards, 1880) and related species (Crustacea: Decapoda: Anomura: Chirostylidae) from the western Atlantic, Zootaxa 4221 (3), pp. 251-290 : 287

Key to species of Uroptychus from the western Atlantic

1. Rostrum subcylindrical. P4 very small, carpus half as long as P3 carpus. Posterior margin of sternal plastron in females strongly excavated, with median parts of sternites 5–7 absorbed into sternite 4 (sternites 5–7 separated into left and right parts)................................................................................. U. brevis Benedict, 1902

- Rostrum flattened triangular. P4 carpus somewhat shorter than or subequal to P3 carpus. Sternites 5–7 in females not separated into left and right parts................................................................................ 2

2. P2–4 dactyli with 2 terminal spines only.............................................. U. fornicatus Chace, 1942

- P2–4 dactyli with row of flexor marginal spines............................................................ 3

3. Sternite 3 anterior margin without pair of submedian spines................................................... 4

- Sternite 3 anterior margin with pair of submedian spines..................................................... 8

4. Sternite 3 anterior margin concave with median prominence. P2–4 propodi with pair of terminal spines preceded by row of