22 PROCEEDINGS OF THE NATIONAL MUSEUM vol.74 



SELENOMYIA VIRENS, new species 



Male. — Dark metallic green in color, the abdomen wholly shining. 

 Arista bare, hypopleural bristles and postscutellum well developed. 

 Front at vertex narrow, only 0.16 of head width. Dimensions of 

 head in micronometer units : height 66 (eye 38) ; length (antennal 

 axis) 48; width 74. Vibrissal axis almost as long as antennal, but 

 both back and front of head recede a little below. Pollen of para- 

 frontals dark gray, that of parafacials decidedly brown, between is 

 a large blackish spot on each side of the base of antennae, most dis- 

 tinct from in front. Vibrissae about two-thirds the length of the 

 third antennal joint above the oral margin; facial ridges densely 

 bristly and decidedly convergent on lowest third; face with thin, 

 sharp carina, forming decided antennal grooves; antennae black, 

 third joint hardly twice the second, arista of moderate length, its 

 penultimate joint distinct but hardly elongated. Palpi dark yellow, 

 of normal size ; proboscis short, fleshy. Beard black. 



Thorax dark green, with three broad stripes of white pollen which 

 are distinct at front edge, but fade on the disk and are hardly visible 

 at the suture. Humeri and sides of thorax before wings also with 

 white pollen. Chaetotaxy: acrostichal 3, 3; dorsocentral 3, 4; hu- 

 meral 6; posthumeral 3; presutural 1; notopleural 2 (with hairs 

 around bases) ; supraalar 3-4; intraalar 3; postalar 2; sternopleural 

 2, 1; scutellum with three large lateral pairs, of which the third 

 might be called large divergent apicals, and one or two pairs of 

 widely spaced smallish discals. Calypters brown with blackish 

 border. 



Abdomen wholly shining dark green; second abdominal segment 

 with two pairs of median marginals and two pairs of discals, one 

 behind the other; third segment with two pairs of discals and a mar- 

 ginal row; fourth segment with a few erect bristles irregularly 

 placed. Fifth sternite deeply cleft, the lobes with hairs only ; genital 

 segments small, dark brown; inner forceps united into a slender, 

 almost needlelike organ, the outer forming broad concave plates as 

 in many dexiids, but in this species decidedly truncate ; penis a very 

 slender black plate with a pale prolongation and at the base a pair 

 of erect bladelike .semitransparent pieces (claspers?). 



Wings subhyaline, first posterior cell open and ending considerably 

 before the apex; fourth vein curved backward at the bend, which is 

 rectangular and slightly rounded; third vein with three or four 

 setules at base. 



Legs black, claws and pulvilli elongated, the latter brownish ; front 

 tibia with two outer bristles; middle tibia with three on outer front 

 side; hind with a few irregular on outer side. 



