BITING MIDGES — WIRTH AND BLANTON 435 



or base of cell M2; costa extending to 0.58 (0.58-0.60, n=10) of 

 distance to wing tip. Halter knob infuscated. 



Abdomen.— Brownish black, cerci yellowish. Spermathecae two, 

 slightly unequal, pyriform, measuring 0.048 by 0.033 mm. and 0.042 

 by 0.026 mm., the bases of the ducts sclerotized a very short distance. 



Male genitalia: Ninth sternum with broad, shallow, caudo- 

 median excavation; ninth tergum long, tapering, with short, pointed 

 apicolateral processes. Basistyle with ventral root foot-shaped, the 

 posterior heel well developed, dorsal root slender; dististyle long and 

 slender with hooked apex. Aedeagus with basal arch rounded, ex- 

 tending to more than half of total length of aedeagus, basal arms 

 slender and nearly straight; distal portion with a slender, tapering 

 median stem with rounded, distally striated, apical point, flanked by a 

 pair of long, triangular, sharp pointed, poorly sclerotized processes 

 arising from main body of aedeagus near base of distal stem. Para- 

 meres each with large basal knob, stem moderately slender, abruptly 

 bent a short distance from base, midportion sinuate and slightly 

 swollen ventrally, distal portion slender, abruptly bent ventrad with 

 pointed apex bearing a few lateral barbs. 



Distribution: Panama; Guatemala; Honduras: 



Specimens examined: Holotype female (USNM 63171), allotype, 

 Fort Davis, Canal Zone, Oct. 7, 1953, F. S. Blanton, light trap. 

 Paratypes, 23 males, 17 females: Panama: Bocas del Toro Province: 

 4 females, Almirante, Nov. 10, 1952, Jan. 18, 1953. Canal Zone: 

 12 males, 2 females, same data as type; 1 male, 3 females, Huile Sia 

 Clara (?), Oct. 13, 1952; 5 males, 3 females, Loma Boracho, Nov. 27, 

 1951, June 14, 1952; 2 females, Mojinga Swamp, Nov. 27, 1951, 

 Nov. 15, 1953. Chiriqui Province: 1 male, Pedregal, Sept. 29, 1952. 

 Dari^n Province: 1 female, El Real, July 1952. Honduras: 3 males, 

 1 female, Lancetilla, Jan. 5, 1953, Jan. 29, 1953, P. Galindo, light trap; 

 1 male, Tela, June 10, 1953, P. Galindo, light trap. Guatemala: 

 1 female, Yepocapa, July 26, 1951, Gibson and Ascoli, at light. 



Discussion: C. spurius is similar to hqffmani Fox, but the latter 

 species differs from it in having the antennal ratio about 0.79, the 

 second palpal segment much shorter than the third (12:19), the third 

 segment even stouter, 1.6 times as long as broad, the wing larger, 

 averaging 0.76 mm. long, and an average of 14 mandibular teeth. 

 The male genitalia of hofmani differ markedly — the apicolateral proc- 

 esses on the ninth tergum much larger, the aedeagus with broadly 

 expanded and well-sclerotized apex with three subequal distal proc- 

 esses. C. imitator Ortiz is also closely related, but it has no definite 

 pit on the third palpal segment and the male aedeagus is broad and 

 truncated distally without distal processes. 



