Opeatocerata megalophallus sp. nov.

(Figs 114–122)

Diagnosis. Epandrium lobe acuminate at apex (Figs 116, 117); phallus narrow, much longer than the hypandrium (Fig. 121); subepandrial sclerite as wide as long (Fig. 120); bacilliform sclerite shorter than subepandrial sclerite (Fig. 120).

Description. Male (Fig. 114). Head: Face slightly divergent toward the proboscis, dark brown, with gray pruinescence visible in ventral view, about 4X longer than lower width. Ocellar tubercle protrubeant, dark brown with gray pruinescence; ocelli brown. Antenna brown to black bristles; postpedicel about 1.5X longer than pedicel; stylus about 1.5X longer than postpedicel. Proboscis yellow shorter than head height. Thorax yellow, shiny (Fig. 114). Legs yellow, except for hind femur and tibia with apical black ring and all tarsomeres 3–5 brown; hind tibia with anterodorsal and posterodorsal rows of longer bristles. Wing (Fig. 115) hyaline, brown pterostigma, conspicuous, about 2.3X longer than wide. Halter yellow. Abdomen yellow, shiny (Fig. 114); tergite 8 divided in two subtriangular plates; sternite 8 divided in two trapezoidal plates. Terminalia: Anterior cercus with proclinate dorsal projection in lateral view (Figs 116, 117), with posterior margin slightly concave in dorsal view (Fig. 118); descendant plate subrectangular in posterior view (Fig. 119). Posterior cercus with acuminate apex in lateral view (Figs 116, 117); with dorsal projections, a subbasal pointed and a submedian subtriangular (Fig. 118). Hypoproct bacilliform lateral view and covering inner surface of the posterior cercus in posterior view (Fig. 117). Epandrial ventral lobe with acuminate apex (Figs 116, 117), with spiniform bristles mesially and longer bristles apically (Fig. 117). Hypandrium longer than wide, with concave apex (Fig. 122), without long bristles. Phallus narrow, much longer than the hypandrium (Fig. 121). Subepandrial sclerite as wide as long, U-shaped (Fig. 120). Bacilliform sclerite without folds and shorter than subepandrial sclerite (Fig. 120). Specimen length: 2.9 mm; wing length: 2.9 mm. Female. Unknown.

Geographical distribution. Costa Rica (San Mateo, Guanacaste) (Fig. 211).

Type material. HOLOTYPE ♂, labelled: Higuito, San Mateo C[osta] R[ica] / Pablo Schild Coll. (USNM). Paratype: Costa Rica, Guanacaste. Bagaces. P.N. Palo Verde. Ext. E. Campo de Aterrizaje, 0–50 m, 16.vii–17.viii.1999, L. Jiménez, Malaise. L_N_ 260952 _385020 #53259 (1 ♂, INBio).

Holotype condition. Left legs lost; right wing mounted on microslide; abdomen in microtube with glycerin.

Etymology. From the Greek mega (long, great) and phallos (phallus), referring to the length of the phallus.

Remarks. Opeatocerata megalophallus sp. nov. differs from other species due to the narrow phallus, much longer than the hypandrium (Fig. 121) (in other species the phallus is either subcylindrical, with a narrow base widening towards the apex or some other shape) and subepandrial sclerite as wide as long (Fig. 120) (in other species it is wider than long or longer than wide).