Opeatocerata brasiliensis sp. nov

(Figs 33–46)

Diagnosis. Yellow species; descendant plate of the anterior cercus subtriangular in posterior view (Fig. 38); phallus narrow, widening toward the apex, with large dorsal subapical appendix (Fig. 40); bacilliform sclerite folded and shorter than subepandrial sclerite (Fig. 39); genital fork with arms longer than base (Figs 44, 46); tergite 10 undivided (Fig. 45).

Description. Male (Fig. 33). Head: Face parallel-sided, brown with gray pruinescence visible in ventral view, about 4X longer than lower width. Ocellar tubercle protuberant, brown with brown pruinescence; ocelli yellow. Antenna yellow with black bristles; postpedicel about 1.5X longer than pedicel; stylus about 2.5X longer than postpedicel. Proboscis yellow shorter than head height. Thorax yellow, shiny (Fig. 33). Legs yellow, except for hind femur and tibia with apical black ring and all tarsomeres 4–5 black; hind tibia with anterodorsal and posterodorsal and anteroventral rows of longer bristles. Wing (Fig. 34) hyaline; pterostigma brown, conspicuous, about 2.8X longer than wide. Halter yellow. Abdomen yellow, shiny (Figs 33, 35); tergite 8 divided in two subrectangular plates; sternite 8 divided in two trapezoidal plates. Terminalia: Anterior cercus with proclinate dorsal projection in lateral view (Fig. 36), posterior margin with median sinus in dorsal view (Fig. 37); descendant plate subtriangular in posterior view (Fig. 38). Posterior cercus with rounded apex in lateral view (Figs 35, 36), with pointed dorsal subbasal projection in dorsal view (Fig. 37). Hypoproct subtrapezoidal in lateral view (Fig. 36) and covering inner surface of the posterior cercus in posterior view (Fig. 38). Epandrial ventral lobe rounded at apex (Fig. 36), with spiniform bristles mesially and longer bristles at base (Fig. 36). Hypandrium longer than wide, with concave apex (Fig. 41), without long bristles. Phallus narrow, widening toward the apex, longer than hypandrium, with large dorsal subapical appendix (Fig. 40). Subepandrial sclerite longer than wide, U-shaped (Fig. 39). Bacilliform sclerite folded and shorter than subepandrial sclerite (Fig. 39). Specimen length: 3.6 mm; wing length: 3.6 mm. Female (Fig. 42). Similar to male, except frons brown, shiny, wider than face. Wing with pterostigma about 2.9X longer than wide (Fig. 43). Terminalia: Tergite 8 subrectangular (Fig. 44). Sternite 8 with base wider, concave and apex rounded (Fig. 44). Genital fork wider than long and arms longer than base, separated at apex (Figs 44, 46). Tergite 10 undivided, with half the length of tergite 8 (Fig. 45). Sternite 10 with base straight and apex bilobed (Fig. 45). Specimen length: 3.3 mm, wing length: 3.3 mm.

Geographical distribution. Brazil (Goiás, Mato Grosso and Pará) (Fig. 211).

Type material. HOLOTYPE ♂, labelled: Brasil, Mato Grosso, Chapada Guimarães, 22–30.xi.1983. J.E. Bindá / armadilha malaise (INPA). Paratypes: Brazil, Mato Grosso. Same data (2 ♂, 4 ♀, INPA). Pará. Marabá, S. Norte. ix.1982. Michael Miles (1 ♂, MPEG). Est[ado] de Goiás. Corumbá, F[azenda]. Monjolinho. Barreto col. (1 ♂, MZUSP).

Holotype condition. Right wing on microslide; abdomen in microtube with glycerin.

Etymology. The specific epithet refers to the country “ Brazil ” where the specimens were collected. Remarks. Opeatocerata brasiliensis sp. nov. differs from other species by the descendant plate of anterior cercus subtriangular in posterior view (Fig. 38) (in other species, the plate is subtrapezoidal, subrectangular, hourglass-shaped or with lateroventral projection), subepandrial sclerite longer than wide, (Fig. 39) (in other species it is wider than long or as wide as long) and hypoproct subtrapezoidal in lateral view (Fig. 36) (rounded, bacilliform or subtriangular in other species).