COPEPODA FROM IFALUK ATOLL 377 



Genus Cletopsyllus Willey, 1935 



This genus is based on Cletopsyllus papillifcr Willey, 1935, the only 

 species known, of which only the female has been described. 



Genus Pseiidocletopsyllus, new genus 



Type and sole species: Pseudocletopsyllus spiniger, new species. 



Diagnosis. — Females: Normanellinae with heavily armed body. 

 Head and 1st thoracic somite fused, epimeral plates of all somites, 

 with exception of abdominal somite 4 and anal somite, laterally pro- 

 duced, backwardly drawn out and pointed. In addition, there are 

 lateral expansions on some of the somites, while cephalic and body 

 somites are distally armed with big spines, the 4th and anal somites 

 excluded. 



Rostrum big, not separated from cephalic somite, bifid at apex. 

 Furcal rami long, tubular, with 2 setae at swollen internal margin and 

 5 marginal setae, 2 of which are lengthened and thickened. Anten- 

 nules 4-segmented: segment 1 with external spine; segment 2 with 2 

 externally directed apophyses, each bearing seta; segment 3 with 

 conical process bearing aesthetasc and 2 seta. Antenna with allobasis 

 and small exopodite, bearing 2 fine setae. Mandible with unseg- 

 mented basipodito, small endopodite, and no exopodite. Structure of 

 maxillule unknown. Maxilla with 2 praecoxal, 1 coxal, and 1 basal 

 endite; basal and coxal endites each with 2 spines and a seta, endopo- 

 dite reduced. Maxillipede with moderately swollen basis; endopodite 

 unsegmented, forming slender digit. Leg 1 with 3-segmented exop- 

 odite, segment 2 without internal seta. 1st segment of endopodite 

 with internal seta; 2nd and 3rd segments fused, with strong seta at 

 place of insertion. Legs 2 to 4 with 3-segmented exopodites and 2- 

 segmented endopodites. The setal formula is given in the following 

 table, in which, for the purpose of comparison, the setal formula of 

 Cletopsyllus papillifer Willey, 1935, also is given. 



specimen leg S leg S leg 4 



endop- exop- endop- exop- endop- exop- 



odite odite odite odite odite odite 



P. spiniger 1.421 0.1.123 1.321 1.1.223 1.321 1.1.223 



C.papillifeT 1.421 0.1.123 1.321 1.1223 1.321 1.1.323 



Leg 5 with baso-endopodites of both sides connected by median 

 plates; jomting between exopodite and baso-endopodite indistinct. 

 External lobe greatly lengthened, with fine seta. Exopodite elongate, 

 with 6 setae. Baso-endopodite slightly shorter than exopodite, with 

 2 apical and 3 internal spines. 



The males are unknovsn. 



Remarks. — Unfortunately, I have to base the description of this 

 new genus on a single female specimen. The dissection of this speci- 



