Heteropsyllus, T. Scott, 1894

Nam, Eun-Jung & Lee, Wonchoel, 2006, Two new species of the genus Heteropsyllus (Crustacea, Copepoda, Harpacticoida) from Jeju Island, Korea and Devon, England, Journal of Natural History 40 (29 - 31), pp. 1719-1745 : 1743-1744

Key to the species of the genus Heteropsyllus (modified from Coull and Palmer 1980)

1. P1 exp-2 with and P4 enp-1 without inner seta.......... 2

– P1 exp-2 without and P4 enp-1 with inner seta.......... 3

2. Enp-1 of P1–P3 with inner seta..... H. pseudonunni Coull and Palmer

– Enp-1 of P1–P3 without inner seta.......... H. nunni Coull

3. Terminal exopodal segment of P1 with four setae.......... 4

– Terminal exopodal segment of P1 with five setae......... 10

4. A2 exp one-segmented................. 5

– A2 exp two-segmented................. 7

5. P1 enp-1 with inner seta........... H. coreanus sp. nov.

– P1 enp-1 without inner seta................ 6

6. P5 baseoendopod and exopod separated.. H. serratus Schriever incertae sedis

– P5 baseoendopod and exopod fused........ H. confluens Soyer 7. Terminal exopodal segment of A2 with three setae......... 8

– Terminal exopodal segment of A2 with four setae..... H. nanus (Sars)

8. Terminal endopodal segment of P4 with three setae.. H. curticaudatus T. Scott

– Terminal endopodal segment of P4 with four setae......... 9

9. Exopod of mandibular palp completely absent...... H. major (Sars)

– Exopod of mandibular palp one-segmented with one seta.. H. celticus sp. nov.

10. Last endopodal segment of P2 with five setae.......... 11

– Last endopodal segment of P2 with four setae.......... 12

11. P1 enp-3 twice as long as enp-2; syncoxa of Mxp with two setae at inner distal corner................. H. exiguus (Sars)

– P2 enp-3 equal in length to enp-2; syncoxa of Mxp with one seta at inner distal corner................ H. meridionalis Soyer

12. Rostrum pointed; P3 enp-3 with five setae........... 13

– Rostrum rounded; P3 enp-3 with four setae...... H. masculus Kunz

13. Baseoendopod of P 5♀ with four setae........ H. rostratus (Sars)

– Baseoendopod of P 5♀ with five setae...... H. rostratus similis Smirnov