no. 3608 CADDIS FLIES, IV — FLINT 9 



Adult. Length of forewing: male 8-9 mm, female 10-12 mm. 

 Color brown, head hairs fuscous, wings brown with many small spots 

 of golden hair. Male genitalia: Anterior margin of ninth segment 

 nearly vertical, posterior margin rounded. Cercus divided into an 

 outer lobe with a slightly differentiated dorsobasal portion and an 

 elongate ventral portion; inner lobe with an enlarged base narrowing 

 to a sturdy, laterally curving process. Clasper somewhat triangular 

 in lateral aspect, with a mesal spine. Aedeagus with apex developed 

 into a trilobed ventral lip, internally with two pairs of short spines, 

 a basal complex of small sclerites, and a pah' of apical plates. 



Holotype, male: Costa Rica, Mount Poas, May, William Schaus. 



Paratypes: Costa Rica, Irazu, 2200-2500 m, May 21-28, 1930, 

 Reimoser, 2 d\ 6 9 (Vienna Museum). 



Polycentropus guatemalensis, new species 



Figure 33 



The species is closely related to P. halidus Milne, from which it 

 differs most noticeably in the sinuate ventral process of the cercus, 

 which is longer and hooked in P. halidus, and the longer and narrower 

 claspers, whose dorsoapical point is displaced slightly basad. 



Adult. Length of forewing: male 6-7 mm, female 8 mm. Color 

 dark brown; body and appendages yellow brown, forewings dark 

 brown with numerous spots of golden hair. Male genitalia: Ninth 

 segment with anterior and posterior margins parallel. Cercus with 

 a broad dorsolateral lobe, an elongate, slightly sinuous ventromesal 

 process, and dorsally with an elongate rodlike process. Clasper long 

 and slender, with dorsal margin forming an anteapical point, a sinuate 

 ridge on inner surface culminating in a basomesal spine. Aedeagus 

 with a large apicoventral process, apicodorsally with flat plates, 

 internally with a pair of spines. 



Holotype, male: Guatemala (Suchitepequez) , Finca Moca, June 12, 

 1966, Flint and Ortiz. 



Paratypes: Same data, 1 d\ 1 9. Guatemala, Chimaltenango, 

 Aug. 19-20, 1965, Spangler, 1 tf 1 . 



Polycentropus aztecus, new species 



Figure 34 



This species is closest to P. bartolus Denning, from which it differs 

 in possessing an arched dorsal process and an apical tooth on the 

 cerci and in having an evenly rounded outline to the clasper. 



Adult. Length of forewing 8 mm. Color dark brown; body and 

 appendages slightly paler, forewings with numerous small spots of 

 golden hair. Male genitalia: Ninth segment with anterior margin 



