Collettea

Key to species of the genus Collettea

(modified after Larsen 2000, Błażewicz-Paszkowycz & Larsen 2005, and Wi et al., 2015).

1. Pereonites 1–3 subequal in length or only slightly increasing in length posteriorly................................... 2

- Pereonites 2 and 3 (or pereonite 3 only) distinctly longer than pereonite 1......................................... 5

2. Cheliped fixed finger with one ventral seta................................................................. 3

- Cheliped fixed finger with two ventral setae................................................................4

3. Pleotelson longer than three pleonites combined. Antenna article-4 with fusion line. Maxilliped endite lacking setae. Cheliped fixed finger cutting edge denticulate along entire margin................................................ C. wilsoni

- Pleotelson as long as or longer than four pleonites combined. Antenna article-4 without fusion line. Maxilliped endite with two pairs of setae. Cheliped fixed finger cutting edge denticulate distally................................ C. bamberi n. sp.

4. Antenna article-4 without fusion line. Maxilliped endite with two pairs of setae............................. C. alicjae

- Antenna article-4 with distal fusion line. Maxilliped endite lacking setae............................. C. cylindratoides

5. Cheliped fixed finger with one ventral seta.................................................................6

- Cheliped fixed finger with two ventral setae...............................................................13

6. Uropod endopod one-articled................................................................ C. longipleona

- Uropod endopod two-articled............................................................................ 7

7. Uropods short (<0.3 times length of pleotelson).............................................................. 8

- Uropods long (> 0.3 times length of pleotelson)............................................................. 10

8. Cephalothorax bearing fine setules on mid-lateral margins. Antenna article-4 with fusion line................... C. eminula

- Cephalothorax lacking fine setules on mid-lateral margins. Antenna article-4 without fusion line....................... 9

9. Pleotelson shorter than pleonites 3–5........................................................... C. prominentia

- Pleotelson longer than pleonites 3–5................................................................ C. subtilis

10. Antenna article-4 with fusion line............................................................... C. longipedia

- Antenna article-4 without fusion line..................................................................... 11

11. Maxillipedal endite with pair of setae.............................................................. C. lilliputa

- Maxillipedal endite without setae........................................................................12

12. Pereonites 4 and 5 longer than wide............................................................ C. longisetosa

- Pereonites 4 and 5 wider than long................................................................ C. minima

13. Pleon shorter than last three pereonites............................................................ C. humbolti

- Pleon longer than last three pereonites.................................................................... 14

14. Uropod endopod one-articled.................................................................... C. pegmata

- Uropod endopod two-articled...........................................................................15

15. Pleotelson as long as pleonites combined length................................................. C. rotundicauda

- Pleotelson shorter or longer than pleonites combined length...................................................16

16. Uropods long (> 0.3 times length of pleotelson).............................................................17

- Uropods short (<0.3 times length of pleotelson)........................................................... 18

17. Antenna article-4 with fusion line............................................................. C. vermiformis

- Antenna article-4 without fusion line.............................................................. C. elongata

18. Antenna article-4 with fusion line........................................................................ 19

- Antenna article-4 without fusion line..................................................................... 20

19. Pleotelson longer than combined length of all five pleonites......................................... C. larviformis

- Pleotelson shorter than combined length of all five pleonites......................................... C. cylindrata

20. Pereonites 4 and 5 longer than wide......................................................................21

- Pereonites 4 and 5 wider than long.......................................................................22

21. Cephalothorax bearing fine setules on mid-lateral margins. Pereon as long as pleon........................... C. aspera

- Cephalothorax lacking fine setules on mid-lateral margins. Pereon longer than pleon........... C. sp. A sensu Larsen, 2005

22. Antennule article-1 longer than last three segments combined........................................... C. arnaudi

- Antennule article-1 shorter than last three segments combined........................................ C. antarctica