Mesorhaga adunca Van Duzee

Mesorhaga adunca Van Duzee (Fig. 2 a)

Condylostylus aduncus Van Duzee 1933: 1.

Type material. Van Duzee described this species as Condylostylus aduncus, wheras it clearly is Mesorhaga, a genus he would have known from his previous work. Robinson (1970) correctly referred this species to Mesorhaga. The male holotype (AMNH, examined) was collected in Guatemala: Guatalon, Moca, 1000 m, iii–iv.1931, J. Bequaert.

Description. Male: body length: 3.9 mm. wing: 3.8 x 1.6 mm.

Head: 3 long postvertical setae present, in line with the postoculars and curving over ocellar tubercle; strong proclinate vertical setae present on lateral frons; vertex, frons, face, and clypeus metallic green, shining, with little pruinosity; antenna black; first flagellomere rounded, subrectangular; arista dorsal, shorter than head height; ventral postcranium with abundant black setae.

Thorax: metallic green with bronze reflections; setae black; pleura with some grey pruinosity; 4 offset pairs long ac present; median scutellars about two- thirds length of medians.

Legs: all coxae dark brown; coxa I with some metallic green reflections; trochanters, femora and all leg III, and tarsi I and II brown; tibiae I & II yellowish; CI and CII with black anterior hairs, CIII with black lateral seta; femora with long, dark brownish, ventral and pv hairs along length; tibiae bare of major setae. I: 4.8; 4.3; 2.7/ 1.0/ 0.7/ 0.5/ 0.4. II: 5.8; 6.4; 4.0/ 1.4/ 1.0/ 0.6/ 0.5. III: 6.3; 7.8; 3.1/ 2.1/ 1.1/ 0.7/ 0.5.

Wing: membrane hyaline; veins pale brown; anal angle well developed; M with almost right-angle bend halfway between dm-cu crossvein and wing apex; CuAx ratio: 0.7; lower calypter dark brown, with fan of black setae; halter dark brown.

Abdomen: terga metallic blue-green, covered with short, dark setae dorsally, with pale setae ventrally and on sterna; with dark, bronze-brown bands present on tergal overlap of segments 2–6; tergum 1 with posterolateral row of long, black setae; hypopygium dark brown (Fig. 2 a), epandrial lobes ovate, with setae at 1/2 and apex; cercus curved, with apical tuft of setae on subrectangular projection.

Female: unknown.

Remarks. Mesorhaga adunca is known from the type locality at 1000 m in Guatemala. This species has relatively long legs when compared to its Mesoamerican congeners.