Key to the species of Pseudosphyrapus, females only unless otherwise stated
1 Rostrum with rounded apex without any denticles......................................... P. centobi Bäcescu, 1981
- Rostrum with distal denticles............................................................................. 2
2 Pleonite epimera rounded............................................................................... 3
- Pleonite epimera pointed................................................................................ 5
3 Antennule article 1 with about ten outer simple setae; outer flagellum three-articulate.... P. gutui Kudinova-Pasternak, 1985
- Antennule article 1 with three–four outer simple setae; outer flagellum five-articulate in female (seven-articulate in male)... 4
4 Pereopod 1 propodus with five ventral and one dorsal spiniform setae. Antennule peduncle consists of three articles + common article....................................................................... P. anomalus (G.O. Sars, 1869)
- Pereopod 1 propodus with four ventral and two dorsal spiniform setae. Antennule peduncle articles 2 and 3 apparently fused (consist of two articles + common article)................................................. P.. sp A Larsen, 2005
5 Processes on epimera of pleonite 5 equal in size to those of pleonites 1–4........................................ 6
- Processes on epimera of pleonite 5 much larger than rest......................... P. quintolongus Kaukui, et al., 2007).
6 Basal article of pleopod with one ventral plumose seta........................................................ 7
- Basal article of pleopod lacks ventral plumose setae......................................... P. vladimiri Guţu, 1989
7.....................Carpus of pereopod 1 with three ventral spiniform setae. Mandible palp with setae on article 2 and 3............................................................................. P. serratus (G.O. Sars, 1882)
- Carpus of pereopod 1 with two ventral spiniform setae. Mandible palp with setae only on article 3................................................................................................. Pseudosphyrapus azorensis n. sp.