(Figs. 1–3)
Type material. Holotype male, USA: South Carolina: Barnwell Co., Savannah River Site, Pen Branch SRS Road B (PBI) 33 ° 12 ’ 30 ’’N, 81 ° 38 ’05’’W; light trap, 12. vi. 1995, leg. M. Womble, 98233.
Etymology. This new species is close to B. nudisquama Caspers et Reiss in the structure of the hypopygium, but can be separated by having three squamal setae and a wing without costal extension.
Male imago (n = 1).
Total length 2.46 mm. Wing length 1.24 mm. Total length/wing length 1.98. Wing length/length of profemur 2.07. Coloration dark brown.
Head. Terminal flagellomere 464 long, without strong subapical seta. AR 1.46. Temporal setae 10; including 4 inner verticals, 2 outer verticals and 4 postorbitals. Clypeus with 6 setae. Tentorium 146 long, stipes 114 long. Palpomere lengths: 28, 52, 100, 74, 128. Sensilla clavata in the 3 rd palpomere not visible.
Thorax. Antepronotum with 2 setae. Dorsocentrals 10, acrostichals 8, prealars 2. Scutellum with 4 setae.
Wing (Fig. 1). Anal lobe normal developed. Moderately coarse punctation easily visible at 100 x magnification. VR 1.16. R 2 + 3 ends 1 / 2 distance between R 1 and R 4 + 5. Costa without extension. Brachiolum with 1 seta; R with 3 setae, remaining veins bare. Cu 1 slightly curved. Squama with 3 setae.
Legs. Spur of front tibia 42 long, without denticles. Spurs of middle tibia 34 and 28 long, of hind tibia 48 and 28. Hind tibial comb with 7 setae. Middle and hind tibial spurs with weak denticles. Pseudospurs absent.
Lengths and proportions of leg segments:
Hypopygium (Figs. 2, 3). Anal point long, parallelsided with blunt apex, 42 long, 10 wide, anal point length/width 4.20. Tergite IX with 6 long setae; laterosternite IX with 8 setae. Phallapodeme 90 long; transverse sternapodeme 90 long, weakly arcuate with oral projection. Virga 42 long, composed of cluster of 4 spines. Gonocoxite 172 long. Gonostylus straight, 76 long. Inferior volsella naked, well sclerotized and somewhat conical with 4–5 basal setae. Crista dorsalis low. Megaseta 10 long. HR 2.26, HV 3.24.
Distribution. The species is only known from the type locality and was collected by light trap.
Remarks. This new species is very similar to B. nudisquama from Austria in the structure of the hypopygium, but can be separated by having three setae on the squama and a wing without costal extension. Female and immature stages unknown.