TYRINI 297 



11. Tergites I, II, III subequal or decreasing in length 



HAMOTOIDES (subgenus of Hamotus) 



Tergites I, II, III increasing in length PHAMISULUS 



12. Sulcus of distal segment of maxillary palpus confined to apical 



half 13 



Sulcus of distal segment of maxillary palpus extending beyond apical 

 half 14 



13. Distal segment of maxillary palpus ovate-cylindrical, obliquely 



truncate at base, with sulcus extending as an elongate fovea on 



apical half of internal face APHARUS 



Distal segment gourd-shaped, narrowed basally, ovate in median two- 

 fifths, and very narrow and elongate-cylindrical in apical half, 

 with a very narrow and striaform sulcus on apical half of internal 

 face CERCOCERULUS 



14. Apex of distal segment of maxillary palpus lengthily very acute to 

 aciculate, with a palpal cone one-third the segmental length set in 



apex and continuing the long axis of the latter 



PSELAPHOCOMPSUS 



Apex of segment obtuse, with a palpal cone set obliquely within the 

 apex of the sulcus of internal face 15 



15. Distal segment of maxillary palpus very elongate-cylindrical, nar- 



row and subfiliform, with the sulcus of internal face deep but very 



narrow 16 



Distal segment ovate-fusiform to ovate-conical, obliquely truncate 

 at base, with a broad sulcus of variable shape, length and depth 

 HAMOTUS ss. 



16. First tergite much longer than other tergites united 



CERCOCEROPSIS 



First tergite varying from slightly longer to distinctly longer than 

 second tergite, but never as long as second and third united. . . . 

 CERCOCEROIDES 



PHALEPSUS (Westwood, 1870) 



This is a moderately large genus of eight elegant species known from 

 Brazil and Paraguay. They are of average size (1.3 to 2.0 mm.) with an 

 elongate-oval, strongly convex outline, very attenuated anteriorly and broadly 

 rounded posteriorly. They bear somewhat the same relation to the other 

 neotropical tyrines as Ephimia does to the other hybocephalines, that is they 

 are aberrant in having the tarsal claws short and very unequal. 



The genus, although highly specialized, clearly belongs to the first division 

 of neotropical tyrines — those having the maxillary palpi nonsulcate. The 

 maxillary palpi are four-segmented, long and slender; the first segment is 

 very small and subcylindrical; second very long, subsinuate and pedunculate 

 through the basal half, becoming inflated apically, with the apical internal 

 face obtusely angulate; third similar in form to second, but much shorter, 



