August, 1944 



Ross: Caddis Flies of Illinois 



161 



ment with a large, clasper-like lobe on the 

 postero-lateral margin, this lobe with the 

 apical margin rounded dorsally and taper- 

 ing to a somewhat pointed ventral corner; 

 tenth tergite membranous and somewhat 

 hood shaped; claspers with a broad base, 

 a small, finger-like dorso-lateral projection 

 and a wide ventro-mesal lobe the apical 

 margin of which is rounded and which bears 

 four to six setae; above the claspers is a 



559 



560 



Fig. 559. — May atrichia ayama cf , spine of 

 sixth sternite. 



Fig. 560. — Mayatrichia ayama 9, bursa 

 copulatrix. 



stout, wide lobe with a long, sharp ventral 

 beaked apex; aedeagus long, slender and 

 simple, the extreme apex divided into a 

 three-pronged sclerotized plate. Female 

 genitalia simple and tubular, with bursa 

 copulatrix large and shaped as in fig. 560. 



This species is the one described by Bet- 

 ten (1934, p. 164) as an undetermined genus 

 and species. 



In Illinois, we have taken the species 

 commonly in the northern fourth of the 

 state and have, in addition, a record from 

 southern Illinois. We have taken the larvae 

 and pupae abundantly in the riffles of the 

 Galena River at Council Hill, Illinois, thus 

 associating the larvae, males and females; 

 we have made similar collections in the Kan- 

 kakee River at Momence. This species has 

 a distinct preference for the more rapid and 

 clear Illinois rivers and streams. Adult 

 emergence extends from June to early Sep- 

 tember, indicating a continuous cycle of gen- 

 erations. 



The range of the species extends from 

 extreme southern Mexico to New York and 

 Montana; most of the records follow fairly 

 closely the confines of the deciduous forests, 

 ranging through Texas into Florida and 

 more northern eastern states; in the north- 

 western states our only record is from Mon- 



tana. Although the records are scattered 

 over a wide area, the species is quite rare 

 and not commonly taken. We have records 

 from Florida, Georgia, Illinois, Iowa, Ken- 

 tucky, Missouri, Montana, New York, 

 Oklahoma, Pennsylvania, Tennessee and 

 Texas. 



Illinois Records. — Many males, females 

 and pupae, taken June 21 to September 10, 

 and many larvae, taken June 6 to August 

 21, are from Amboy (Green River), Apple 

 River Canyon State Park, Council Hill 

 (Galena River), Dixon, Elizabethtown, 

 Kankakee, Momence, Oregon, Ottawa, 

 Rock Island, Serena. 



PHRYGANEIDAE 



In this family the maxillary palpi are 

 four segmented in the male, five in the fe- 

 male. The larvae construct cases which in 

 most genera are long and built in a spiral. 

 Characteristic of the larvae are their mem- 

 branous meso- and metanotum, each with a 

 lateral tuft of long setae; in addition, the 

 lateral gills are covered with hair, and the 

 lateral line of the abdomen is represented 

 by a fairly wide area of short hair. 



The generic limitations in this family have 

 previously been established on the basis of 

 wing venation and vestiture. Both of these 

 characters, however, vary so much in some 

 genera that it is impractical to use these as 

 a basis for generic differentiation in this 

 family. The best characters for this pur- 

 pose seem to be the female genitalia, which 

 present some striking evidences of both 

 differentiation and affinities, and the generic 

 groupings outlined here are based on these 

 characters. 



The genus Neuronia Leach, used com- 

 monly in the past as a caddis fly genus of 

 this family, apparently belongs to the Ple- 

 coptera, with Phryganea fusca Linnaeus as 

 the type. 



In general, the family favors marshes and 

 lakes for its abode, but some species are 

 taken in rivers and streams. 



KEY TO GENERA 

 Larvae 



1. Frons with a median black line, fig. 



561 ;•• 2 



Frons without a median black line, 

 fig. 564 3 



2. Pronotum with anterior margin black, 



