NO. 3571 RED SEA OSTRACODS — KORNICKER 13 



claw. Lamella near basis of claws with long hairs. Primary claws 

 1 and 2 with double row of teeth, claws 7 and 12 without teeth; 

 secondary claws with marginal spines. Distribution of primary and 

 secondary f ureal claws on 2 specimens is as follows: 



Eyes: Large medial eye (fig. 5A); lateral eyes not observed. 



Frontal organ (figs. hg,h) : 2-jointed with distal joint 3 times length 

 of proximal joint; tip rounded; surface of 2nd joint and distal end of 

 1st joint with fine spines. 



Remarks. — Extreme sexual dimorphism among some species of 

 ostracods creates inherent difficulties in relating males and females 

 with certainty. Carapace morphology in the region of the rostrum 

 and rostral incisure between males and females of Euphilomedes polae 

 identified herein is sufficiently similar to warrant considering them as 

 conspecific in spite of some differences in appendage morphology. 

 Both males and females were collected in the same area. The male 

 and female of E. arostratus Kornicker, a closely related species, have 

 similar dimorphism. 



Some differences in morphology between males and females of E. 

 polae and E. arostratus are compared as follows: 



number of secondary furcal claws 



cleaning bristles in distal group of 7th limb 



number of hairs in row on inner lamella 

 behind rostrum 6 9 9-11* 11 



*The male of E. arostratus described from the Maldive Islands (Kornicker, 



1967) has 9 to 10 hairs, whereas the Red Sea form described in this paper has 11. 



Comparisons. — Euphilomedes polae is closely related to E. arostratus 

 Kornicker but may be differentiated from that species by the shallower 

 rostral incisure with a lateral shield, the subterminal location of 

 bristles on the 2nd joint of the endopodite of the 2nd antenna of 

 the male, and the lower number of bristles on the anteroventral part 

 of the inner lamella of the carapace: 5 compared to 16-21 on E. 

 arostratus. 



