249 

 Denning: Trichoptero 



from lakes to rapid rivers. In California three genera 

 and nine species have thus far been collected. 



Key to Genera 6 

 Adulti 



1. Front tibia with a preapical spur 2 



— Front tibia without a preapical spur 6 



2. Both pairs of wings with R a present, R a branches 

 from Rj at radial cross vein 



Phylocentropus Banks 1907 



— Both pairs of wings with R 2 absent, or branching from 

 R s near margin of wing 3 



3. Hind wings with media 3-branched 



Neureclipsis McLachlan 1864 



— Hind wings with media 2-branched 4 



4. Rj present in both wings or in either the front or the 

 hind wings Polycentropus Curtis 1835 



— R a lacking in both pairs wings 5 



5. Maxillary palpi with 3rd segment only slightly longer 

 than second Cyrnellus Banks 1913 



— Maxillary palpi with 3rd segment 3 times as long as 

 second Nyctiophylax tsrauer 1865 



6. Maxillary palpi with 2nd segment having apex de- 

 veloped into a protuberance C ernotina Ross 1938 



— Maxillary palpi with 2nd segment uniformly and evenly 

 cylindrical 7 



7. Maxillary palpi with 3rd segment longer than 2nd; 

 middle legs of female not dilated 



Tinodes Stephens 1829 



— Maxillary palpi with 3rd segment not longer than 2nd; 

 middle legs of female dilated 8 



8. Apex of fore and hind wings somewhat rounded 



Lype McLachlan 1879 



— Apex of fore and hind wings somewhat pointed 



Psychomyia Pictet 1 834 



Key to the Known Larvae 7 



1. Anal hooks with a row of 4 or 5 long teeth along inner 

 ventral margin; 10th segment short, with scarcely any 

 ventral margin; mentum forming a pair of distinct 

 sclerotized plates Psychomyia Pictet 1834 



— Anal hooks with at most very short, inner teeth; 10th 

 segment longer and tubular; mentum not divided into 

 2 sclerotized plates 2 



2. Mandibles short and triangular, each with a large, 

 thick brush on the mesal side 



Phylocentropus Banks 1907 



— Mandibles longer, with only a thin brush on left man- 

 dible, none on the right 3 



3. Basal segment of anal appendages (10th segment) 

 without hair; left mandible with basal tooth small and 

 with a linear brush on mesal face near base 



Neureclipsis McLachlan 1864 



— Basal segment of anal appendages (10th segment) 

 with long hair; left mandible with basal tooth large, 

 subequal to one above and with brush small 



Polycentropus Curtis 1835 



Genus Polycentropus Curtis 1835 



This is the dominant genus in the family and contains 

 about one-half of the described species. Three species 

 are known to occur in California. The adults are 

 moderate in size, generally 8 to 11 mm. in length, 

 and are usually dark gray in color. Adults are fre- 

 quently collected along the shores of lakes. 



Fig. 10:17. Male genitalia, a, Polycentropus halidus, lateral; 

 b, Polycentropus varlegatus, lateral; c, Psychomyia flavida, 

 lateral; d, Tinodes belisa, lateral; e, Tinodes consueta, lateral; 

 e t , aedeagus and sheaths, dorsal; e 2 , ventral view of genitalia 

 (a,b, Denning, 1948a; c, Ross, 1938; d, Denning, 1950b; e, Kim- 

 mins and Denning, 1951). 



Key to Adult Males 



1. Clasper narrow, much longer than wide 2 



— Clasper with basal half wide, length only slightly 

 more than the width (fig. 10:16/); Plumas County 



flavus (Banks) 1908 



2. Clasper long, slender, about the same width through- 

 out (fig. 10:176); Shasta County to Alameda and Fresno 

 counties variegatus Banks 1900 



— Clasper short, apical portion narrowed, upturned 

 (fig. 10:17a); Santa Clara County to Los Angeles County 



halidus Milne 1936 



'Slightly modified from Ross (1944). 

 'Slightly modified from Ross (1944). 



Fig. 10:18. Male genitalia of Psychomyia lumina. a, lateral view; 

 Oj, tenth tergite, dorsal; Oj, claspers, ventral (Ross, 1938a). 



