66 



Illinois Natural History Survey Bulletin 



Vol. 23, Art. 1 



ous inconspicuous light areas forming an 

 indistinct, irrorate pattern. General struc- 

 ture typical for genus. Front and hind 

 wings with R., present. Male genitalia, fig. 

 245, typical in general for the maculatus 

 group; ninth sternite deep; cerci fairly 

 stocky, the ventral corner fairly sharp, the 

 dorsal angle produced into a long, slender, 

 sclerotized, sinuate rod which curves dorsad 

 at the tip; claspers with baso-dorsal lobe 

 of moderate length, its neck long and slen- 

 der, the apex large and produced into a 

 large mesal point; ventral aspect of claspers 

 with base large and rectangular, narrow- 

 ing suddenly to a slender and somewhat 

 digitate tip; aedeagus curved ventrad and 

 slightly enlarged at apex. 



Female. — Length 9.5 mm. In color and 

 structure similar to male. Genitalia, fig. 

 256, with eighth sternite fairly narrow, Its 

 extreme apex produced into a slight lobe; 

 lateral lobes wide apart at base, fusiform 

 and narrow. 



Holotype, male. — Costello Lake, Algon- 

 quin Park, Ontario: June 22, 1939, Cage 

 No. 1, W. M. Sprules. 



Allotype, female. — Same data as for 

 holotype. 



Paratypes. — New York. — Bear Brook 

 near Blue Mountain Lake, Adirondack 

 State Park: June 19, 1941, Frison & Ross, 

 \$. 



Ontario. — Same data as for allotype, 

 1 $ ; same data except June 11, 1 ^ . 



The elongate, sinuate and upturned fila- 

 ment of the cerci will distinguish this spe- 

 cies from others in the maculatus group, to 

 which it belongs. The ventral aspect of the 

 claspers, fig. 245, is also unique for the 

 group. 



Not known from Illinois but may be 

 taken in future collecting. 



Polycentropus species a 



Larva. — Unknown. 



Adults. — Length 7-9 mm. Male un- 

 known. Female genitalia, fig. 254, with 

 eighth sternite almost evenly tapering from 

 base to apex, more or less triangular, the 

 lateral margins sclerotized; lobes slender 

 and pointed. Ninth segment with ovate 

 sclerotized processes which are short, round- 

 ed at apex, and connected to conical bursa 

 copulatrix by a narrow ribbon which forms 

 a narrow ventral bridge ventrad of bursa. 



This form is known only from Herod, 



Illinois, and Hopkinsville, Kentucky. It is 

 either the female of carolinensis or repre- 

 sents a new species. 



Illinois Records. — Herod: May 8, 1936, 

 Ross & Mohr, 1 ? ; May 10, 1935, C. O. 

 Mohr, 2?. 



Polycentropus carolinensis Banks 



Polycentropus carolinensis Banks (1905^, p. 



217); cf. 



This species, known only from the unique 

 male type, has not been taken in Illinois. 

 There is a possibility, however, that the 

 unassociated female, Polycentropus species 

 a, may be carolinensis. This has no statisti- 

 cal basis but is a possibility because, in the 

 maculatus group of seven species, carolin- 

 ensis is the only male with which a female 

 has not been associated definitely, and spe- 

 cies a is the only female not definitely asso- 

 ciated with a male. 



Polycentropus pixi new species 



Male. — Length 7 mm. Color various 

 shades of brown, the legs paler, the hind 

 tibiae dark brown with a basal white an- 

 nulus, the front wings with only a few 

 indistinct light spots. General structure 

 typical for genus. Wing venation with R., 

 present in both wings, but only faintly indi- 

 cated in the hind wings. Male genitalia, 

 fig. 247, typical for the maculatus group in 

 general structure as follows: ninth sternite 

 deep; cerci fairly wide, the apical needle-like 

 projection nearly straight and extending 

 considerably posterad, not recurving toward 

 ventral margin of cerci; tenth tergite long, 

 the pair of sclerotized styliform processes 

 very long; claspers with ventral aspect only 

 slightly narrowed at apex, the dorsal mar- 

 gin with a sharp lateral edge and with the 

 mesal margin produced into a sharp tooth 

 near middle; baso-dorsal lobe of clasper 

 long, arched, the mesal point not sharp but 

 well differentiated at the end of the long, 

 necklike portion; aedeagus only slightly 

 curved at apex, which is slightly enlarged. 



Female. — Length 8 mm. In color and 

 general structure similar to male. Eighth 

 sternite, fig. 255, very broad, the corners 

 heavily sclerotized; lateral lobes of sternite 

 long, narrow and widely separated at base. 



Holotype, male. — North Woodstock, 

 New Hampshire: June 21", 1941, at light, 

 Frison & Ross. 



