150 American Midland Naturalist Monograph No. 3 



LARVA. (Fig. 77). — Head much wider than long. Antenna longer than 

 head, spinose; antennal tuft multiple, barbed, inserted a little beyond middle 

 of shaft and not reaching tip. Head hairs: Preantennal (A) multiple, barbed, 

 not reaching insertion of antennal tuft; lower (B) and upper (C) double, 

 barbed, extending to or beyond preclypeus (one branch of each tuft a little 

 shorter and weaker than the other); postclypeal (d) small, multiple; sutural 

 (e), trans-sutural (f) and supraorbital usually multiple. Upper lateral abdoru' 

 inal hairs multiple on segments I to VII, those on segments I and II longer. 

 Comb of eighth segment of seven scales in a curved row; individual scale trifid 

 with subapical spines about one-third as long as apical spine. Siphon strongly 

 inflated, about four times as long as basal width; pecten of 3 to 4 widely 

 spaced teeth on basal fourth of siphon; individual pecten tooth with a coarse 

 basal side tooth; subventral tuft minute, multiple, about as long as apical 

 pecten tooth, inserted laterally at apical third of siphon; hair of dorsal valve 

 longer than apical width of siphon. Anal segment longer than wide, completely 

 ringed by the dorsal plate; lateral hair small, usually multi-branched beyond 

 middle; dorsal brush consisting of a long lower caudal hair and a short multiple 

 upper caudal tuft on either side; ventral brush extending almost the entire 

 length of the anal segment; gills 4, longer than the segment, each gradually 

 tapering to a point. 



distribution. — Midwestern United States. The distribution of this species 

 is not fully known. Southern States: Arkansas and Missouri (153). Other 

 States: Kansas, Oklahoma, South Dakota and Texas (153). 



BIONOMICS. — Rozeboom (157) states that the larvae are found in heavily 

 shaded, temporary, rain-filled pools. Rozeboom (159) reports that the males 

 can be identified, even while resting, by their bulbous terminalia. 



Psorophora (Janthinosoma) varipes (Coquillett) 



Conchiliastes varipes Coquillett, 1904, Can. Enl., 36:10. 



Psorophora discrucians Howard, Dyar and Knab (not Walker). 1917, Mosq. N. and 

 Cent. Amer. and W. I., 4:569. 



ADULT female. — Medium sized species. Head: Proboscis dark scaled; palpi 

 short, dark, about one-fifth as long as proboscis. Occiput with pale erect forked 

 scales centrally; broad appressed yellow or cream-colored scales dorsally, extend- 

 ing forward to rear margin of eyes; and broad appressed dark and purplish 

 scales laterally. Thorax: Scutum with a broad longitudinal stripe of dark 

 lanceolate scales; this longitudinal stripe margined laterally with rather broad 

 yellowish-white scales extending down over the posterior pronotum anteriorly 

 (Fig. 78C). Abdomen: First tergite dingy-white scaled; remaining tergites 

 dark scaled with purplish reflections except for whitish or pale yellow scales 

 on apico-lateral angles; sternites primarily white scaled on segments II to VI, 

 dark on segments VII. Legs: Knee spots present on middle and hind legs; 

 basal two-thirds of femora I and III pale scaled on both inner and outer 

 surfaces; femur II mainly dark scaled on outer surface, pale scaled at basal 

 one-third on inner surface. Tibiae and tarsi of fore and middle legs entirely 



