August, 1944 



Ross: Caddis Flies OF Illinois 



279 



Male. — Length 2.5 mm. Color brown 

 without any conspicuous or distinctive mark- 

 ings. General structure typical for genus. 



Male genitalia as in fig. 930. Ninth seg- 

 ment short, its posterior angle slightly ob- 

 tuse, its posterior margin with a large, 

 triangular, dorsal lobe bearing a line of 

 setae near apex, and with a mitten-like 

 projection below the triangle; this projec- 

 tion with its main body oval, concave on 

 its mesal face, with a sclerotized point near 

 apex and with a more or less thumblike 

 postero-ventral process. Tenth tergite semi- 

 membranous and more or less hood shaped. 

 Claspers with a broad base, a somewhat 

 sinuate, digitate dorso-lateral lobe and a 

 truncate, ventro-mesal lobe which bears 

 at its apex three long, strong setae the bases 

 of which are almost contiguous. Above the 

 claspers is a long, sclerotized, beaklike struc- 

 ture which is wide at apex and bears a pair 

 of small setae. Aedeagus long and simple, 

 the extreme apex tapering to a very slender, 

 filiform style. 



Holotype, male. — Turner Falls State 

 Park, Oklahoma, along Honey Creek: June 

 2, 1937, H. H. Ross. 



Paratypes. — Oklahoma. — Same data as 

 for holotype, 5 <^ . Reagan, along Penning- 

 ton Creek: June 1, 1937, H. H. Ross, 4^. 

 Turner Falls State Park: June 7, 1938, 

 Carl F. Grubb, 1 ^ . 



This species has always been taken in 

 company with ayama, and no female has 

 been differentiated in these collections which 

 could be associated definitely with ponta. 



Mayatrichia acuna new species 



This species is most closely related to 

 ponta but may be readily distinguished from 

 it by the very small dorso-lateral lobe of the 

 claspers and the undulate margin of the 

 meso-ventral lobe with its staggered and 

 well-separated short setae. 



Male. — Length 2 mm. Color light 

 brown, without conspicuous markings. Gen- 

 eral structure typical for genus. Male geni- 

 talia as in fig. 931. Ninth segment with the 

 anterior projections of the lateral margin 

 acute, the dorsal portion of this segment 

 bearing an indefinite patch of setae, the 

 postero-lateral margin with a long, mitten- 

 like lobe which tapers gradually from the 



930B 

 Figs. 929-931. — Mayatrichia, male genitalia. .1, lateral aspect; B, ventral aspect; C, aedeagus. 



