MARINE AMPHIPODA IN MICRONESIA — ^BARNARD 525 



The species is figured again herein to give all the mouthparts in 

 perspective and to add a figure of the third uropod. 



The specimens at hand differ from the original description in one 

 important point, possibly of subspecific value: the greatly produced 

 tooth on the lower corner of the third pleonal epimeron. I hesitate 

 to erect a new species on this basis because dexaminids are known to 

 vary greatly (witness Polycheria antarctica) and the original descrip- 

 tion may have been in error, although Schellenberg (1928) makes no 

 mention of it. 



Distribution: Red Sea; Ifaluk AtoU, Caroline Islands. 



Family Aoridae 



Genus Lembos Bate 

 Key to the Males 



1. Posterodistal end of article 2 on gnathopod 1 with a brush of setae (6 or 



more setae) 2 



Posterodistal end of article 2 on gnathopod 1 lacking a brush of setae . . 5 



2. Pereopod 2 with a strongly setose fourth article L. hirsutipes 



Pereopod 2 with a poorly setose fourth article 3 



3. Pereopod 1 with a strongly setose fourth article L. megacheir 



Neither pereopods 1-2 with strongly setose fourth articles 4 



4. Palm of gnathopod 1 oblique and bearing a sharp medial tooth . L. longipes 

 Palm of gnathopod 1 transverse, slightly chelate, lacking medial process. 



L. arcticus 



5. Coxa 1 distinctly rounded at anteroventral corner 6 



Coxa 1 pointed at anteroventral corner 14 



6. Article 6 of gnathopod 1 essentially bifid, forming a large tooth on posterior 



edge L. jassopsis 



Article 6 of gnathopod 1 not bifid in this manner 7 



7. Article 4 of gnathopod 2 with acute hindprocess 8 



Article 4 of gnathopod 2 lacking acute hindprocess 9 



8. Article 2 of gnathopod 2 inflated, article 3 with sharp anterior process. 



L. bryopsis, new species 

 Article 2 of gnathopod 2 slender, article 3 not produced . . . L. hastatus 



9. Article 5 of gnathopod 1 less than one third as long as article 6 10 



Article 5 of gnathopod 1 more than half as long as article 6 11 



10. Palm of gnathopod 1 transverse, slightly chelate, article 6 slender. 



L. chelatus 



Palm of gnathopod 1 oblique, defining tooth not reaching a transverse line 



from hinge, article 6 stout L. processifer 



11. Palm of gnathopod 1 strongly excavate, with large defining tooth. 



L. philacanthus 

 Palm of gnathopod 1 not excavate, defining tooth small or absent . . .12 



12. Gnathopod 1, anterior and posterior edges of article 6 nearly parallel. 



L. tetracanthus 

 Gnathopod 1, article 6 inflated, anterior and posterior edges biconvex . . 13 



13. Palm of gnathopod 2 long, article 7 about as long as hindmargin of article 6. 



L. francanni 



