Macunahyphes incognitus sp. nov.

(Figs. 9, 17)

Material. Holotype 3 imago (slide 43) from Brazil: Para, río Xingú, Campament S 3° 39' – W 52° 22', ca. 60 km S Altamira, 1 to 21/X/1986, P. Spangler & O. Flint cols. Deposited at INPA.

Male imago. Length (mm): body, 2.1; fore wing, 2.2; hind femur, 0.4. General coloration whitish yellow. Head yellowish white, ventrally with a pair of small submedian gray marks on submentum. Thorax. Prothorax whitish shaded dorsally with black; meso- and metathorax yellowish, shaded dorsally with gray. Hind legs whitish. Fore wings (Fig. 17) with hyaline membrane except around basal half of vein Sc, shaded with gray; veins C, Sc and R1 blackish, R2 grayish, remaining veins whitish translucent, grayish cross veins on Sc and R sectors. Abdomen whitish. Genitalia: forceps absent, styliger with a pair of sublateral acute projections on hind margin; penes completely fused apically, with subquadrate base, narrowing abruptly on median zone, and with a ventral structure (Fig. 9). Caudal filaments (only basal segments present) whitish translucent.

Etymology. From Latin incognitus (meaning unknown, strange) because of the scarcity of the material and the unusual genitalia.

Discussion and diagnosis. Characters that distinguish Macunahyphes incognitus from all other Leptohyphidae, including M. australis, are listed in the diagnosis of the previous species. M. incognitus can be distinguished from M. pemonensis by: 1) smaller size, with a relatively shorter and broader wing (Fig. 17); 2) penes (Fig. 9) with a subquadrate base, and almost completely fused apically; and 3) posterolateral projections of styliger less developed (pps in Fig. 9).