10 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 123 



rounded. Cercus with dorsolateral lobe continuing evenly into a 

 decurved apical hook and a small ventral lobe; with a short, slighly 

 arched, dorsal process. Clasper short and rounded, with a mesal 

 ridge bearing a sharp tooth near apex. Aedeagus with a sharply 

 decurved apicoventral lip, dorsolateral plates, and many small in- 

 ternal spines. 



Holotype, male: Mexico (Michoacan), Insurgente Morelos National 

 Park, east of Morelia, July 14, 1966, Flint and Ortiz. 



Paratype: Mexico (Morelos), Cuernavaca, June, collection N. 

 Banks, 1 cf (Museum of Comparative Zoology). Mexico (Durango), 

 10 miles west of El Salto, 9000', June 25, 1964, J. E. H. Martin, 1 tf; 

 same except July 15, 1 cf ; same except July 28, 1 c? ; same except 

 July 29, 2 cf; same except August 6, 1 c? (Canadian National 

 Collection). 



Xiphocentron aureum, new species 



Figures 35, 36 



Closely related to X. bilimeki Brauer, this species differs in the 

 elongated bifid apex of the ninth sternum, enlarged apex of the 

 aedeagus, and other small details of the genitalia. 



Adult. Length of forewing 8.5 mm. Facial hairs, body, and legs 

 golden; antennae, foretibiae and tarsi, body hairs, and wings fuscous. 

 Hind tibiae slightly enlarged, with a single very large apical spur 

 extending slightly more than half length of basitarsus. Male geni- 

 talia: Dorsal bridge of ninth segment narrow, ninth sternum pro- 

 jecting mesally, tip of projection bifid. Tenth tergum broad in lateral 

 aspect, narrow from dorsum. Cercus elongate, in lateral aspect 

 about eight times as long as wide. Clasper bearing a large setal 

 patch mesally, apex narrow and curving dorsomesally. Aedeagus 

 very slender, over twice as long as combined length of ninth segment 

 and cercus, tip enlarged. 



Holotype, male: Mexico (Vera Cruz), near Huatusco, July 25-26, 

 1965, Flint and Ortiz. 



Hydroptilidae 



Leucotrichia viridis, new species 



Figures 37-39 



This species is related to L. sarita Ross although the aedeagus more 

 closely resembles that of L. pictipes (Banks). From both it is dis- 

 tinguished easily by the patch of bright green setae on the forewing. 

 The clasper is narrower than in any other described species and the 

 structure of the aedeagus is unique in detail. 



Adult. Length of forewing 3 mm. Color grey, antennae with a 

 subapical group of pale segments, face and tegulae with green hairs, 



