Brachypogon (Isohelea) cuacuahuitlus Huerta & Borkent

(Figs 3–5)

Brachypogon (Isohelea) cuacuahuitlus Huerta & Borkent, 2005. Folia Entomológica Mexicana, 44 (Supl. 1):115 (male, figs: palpus, antenna, wing, male genitalia, aedeagus). Borkent & Spinelli, 2007:79 (in Catalog of the Ceratopogonidae of the Neotropical Region); Borkent, 2015:118 (in online World catalog of biting midges).

Description. Female. Head dark brown. Eyes with interfacetal spicules, abutting medially for length of 4–5 ommatidia (Fig. 3 A). Clypeus with three pairs of lateral setae. Scape with two setae; pedicel dark brown, flagellum entirely pale brown, with 13 flagellomeres (Fig. 3 B); flagellomeres 2–8 almost as long as broad, 9–13 elongate, approximately two X longer than broad, AR 1.09; flagellomere 1 with five apical sensilla coeloconica. Palpus (Fig. 3 C) brown, third segment stout, with subapical, shallow sensory pit; fourth segment with one seta; PR 1.33. Mandible with 9–10 apical teeth.

Thorax. Uniformly dark brown. Scutellum with four setae, katepisternum with one slender seta. Legs brown, tarsi paler; hind tibial comb with 6 spines; foreleg TR 2.2, midleg TR 2.1, hind leg TR 2.5; tarsomeres 4 subcylindrical; tarsal claws with internal basal teeth, unequal and longer in foreleg, equal and short in mid-, hind legs. Wing (Fig. 4 A) length 0.73 mm, width 0.32 mm, CR 0.61; membrane slightly infuscated; macrotrichia present in margin of cells r3, m1, m2, cua1 and anal; two radial cells, each with very narrow lumen; radial veins, M thick, pale brown; costa with row of 23 marginal setae, base of R1 with 4 setae, R3 with 2 setae, M2 not visible. Halter pale brown.

Abdomen (Fig. 4 B). Dark brown. Sternite 8 separated medially, each portion stout, quadrangular; sternite 9 sinuate; sternite 10 triangular with one pair of setae. Two ovoid spermathecae (Fig. 4 C) with well-developed necks, measuring 0.05 X 0.042 mm and 0.042 X 0.037 mm.

Distribution. Mexico (Jalisco, Biology Station of Chamela) (Fig. 5).

Taxonomic discussion. Females and males were collected in the same date and locality. This species keys out to couplet 6 in Spinelli & Cazorla (2004), where B. wirthi Spinelli (1990) from northwestern Argentina and B. pallidipennis Spinelli & Grogan (1994) from Honduras are recognized. However, in B. wirthi the stigma is yellowish and the spermathecae are equal-sized, and in B. pallidipennis all tarsal claws are unequal-sized, the second radial cell is minute and the spermathecae necks are deeply oblique.

Material examined. 8 females, 5 males. (Slide mounted), Mexico, Jalisco, Station Biological of Chamela, 19°29´54´´ N, 105°02´41´´W, 5–7 july-1993, Malaise Trap, Coll. Wharton & Sharkey.