468 PROCEEDINGS OF THE NATIONAL MUSEUM vol. io9 



Thorax. — Mesonotum uniformly dull dark brown, almost black, 

 with abundant vestiture of semi-appressed, fine, black hairs and 

 coarse, suberect, black bristles. Scutellum, postscutellum and pleuron 

 uniformly blackish. Legs uniformly dark brown, hind tibia with a 

 faint basal pale ring; femora rather stout as in species of the pachymerus 

 group; legs with abundant bristly hairs; hind tibial comb with four 

 (n=9) spines, the one nearest the spur longest. 



Wing.— Pattern as figured; second radial cell blackish, very long, 

 about three times as long as broad; three yellowish areas on anterior 

 part of wing, a broad one at base of wing, one over r-m crossvein 

 broadly to middle of cell M2, and a small narrow poststigmatic spot; 

 wing otherwise uniformly grayish, darker along veins, sometimes with 

 other very faint pale spots, one in distal part of anal cell, one in cell 

 M4 and one in cell M2 behind medial fork. Macrotrichia entirely 

 absent; costa extending to 0.64 (0.63-0.66, n=9) of distance to wing 

 tip. Halter brownish. 



Abdomen.— Dull blackish. Spermathecae two, pyriform, subequal, 

 each measuring 0.053 by 0.031 mm., the bases of the ducts sclerotized a 

 considerable distance. 



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

 median excavation; ninth tergum broad, with very small apicolateral 

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

 slender; dististyle long and slender with bent, pointed tip. Aedeagus 

 with narrow, pointed basal arch extending to two-thirds of total length, 

 the basal arms stout and nearly straight; distal portion broad with a 

 rounded median lobe and a pair of subapical points. Parameres each 

 with large basal knob, stem bent slightly near base, straight and 

 moderately stout on midportion, ventral lobe absent, tapering to 

 flattened, laterally fringed, bladelike tip. 



Distribution: Guatemala; Mexico; Panama. 

 Panama records: 

 Canal Zone: Loma Boracho, Mojinga Swamp. 



Discussion: The relations of this species are obscure. In some 

 respects it shows affinities with species of the pachymerus group and 

 in others with alahialinus and gorgasi of the furens group, but more 

 likely it is not closely related to any of these. Gibson and Ascoh 

 (1952) found stigmalis to be a common man-biter in Guatemala. 



Subgenus Culicoides (Macfiella) Fox 



Macfiella Fox, 1955, Journ. Agr. Univ. Puerto Rico, vol. 39, p. 217. (Type: 

 Ceratopogon phlebotomus Williston.) 

 Medium-sized species with the second radial cell very dark; wing 

 with the pale spot present straddling middle of vein M2; mesonotum 



