I Concholestes

1. Coxal plate 2 width twice length; gnathopod 2 propodus posterior margin with large rounded hump proximally; uropod 1peduncle with lateral row of robust setae................................................. C. dentalii Giles, 1888

- Coxal plate 2 about as long as wide; gnathopod 2 propodus posterior margin weakly convex proximally; uropod 1 peduncle with 2 lateroapical robust setae........................................................... C. omani Just, 1987 J Caribboecetes (modified from Ortiz and Lemaitre, 1997)

1. Antenna 2 longer than cephalon and pereon combined; cephalon and first 3 -5 pereonites with transverse rows of polyflagellate setules dorsally...................................................................................... 2

- Antenna 2 shorter than cephalon and pereon combined; cephalon and pereon at most with scattered dorsal setules........ 4

2. Eyelobes with apical projection (also visible in dorsal view); peduncular article 5 and flagellar article 1 of antenna 2 with dorsolateral setae in a single distinct longitudinal row; part of coxal plate 7 and article 2 of pereopod 7 with densely setose lateral surface............................................................................................. 3

- Eyelobes apically rounded; dorsolateral setae on peduncular article 5 of antenna 2 not in a single row; coxal plate 7 and article 2 of pereopod 7 with smooth lateral surface............................................. C. barbadensis Just, 1983

3. Basis of pereopods 3 and 4 with longitudinal row of setae on lateral surface; lateral seta on coxal plate 7 and basis of pereopod 7 covering anterior half of surface.................................................... C. jenikarpae Just, 1984a

- Basis of pereopods 3 and 4 without setae on lateral surface; lateral seta on coxal plate 7 and basis of pereopod 7 covering anterior quarter of surface................................................... C. progreso Paz-Ríos & Ardisson, 2013

4. Rostrum strongly downward curved; article 1 of antenna 1 with broad, marginally setose lateral ‘wing’................................................................................................. C. pterycornis Just, 1984a

- Rostrum straight; article 1 of antenna 1 normal, without lateral wing............................................. 5

5. Coxal plates 1 and 2 more than twice as long as wide at base, pointed; gnathopod 1 propodus 5.5 times longer than wide, anterior and posterior margins parallel............................................ C. guitarti (Ortiz & Nazabal, 1984)

- Coxal plates as long as broad at base, apically rounded (1 occasionally more pointed).............................. 6

6. Medial face of article 1 antenna 1with several robust setae on; gnathopod 2 propodus with 3 robust setae on posterior margin................................................................................ C. intermedius Just, 1984a

- Medial face of article 1 of antenna 1 without robust setae; gnathopod 2 propodus with a single robust setae on posterior margin............................................................................ C. justi Ortiz & Lemaitre, 1997