7-8mm. This species resembles B.modesta Warren but is
much paler, the male lacking the strong white fleck between the angles of the
forewing postmedial. The male costa is only weakly bowed and lacks any scale
crest. The fasciation is neat and regular, darker brown on the pale brown
ground, the angles of the postmedials rather rounded, with a paler edging
distally. The aedeagus is larger, tapering more from a bulbous base. The
octavals are simple, separate, apically acute, whereas in modesta they
form a broadly triangular plate, apically convergent and bilobed. The female
genitalia have short, narrow ductus and a large, pyriform bursa more or less
full of delicate spining that is more concentrated in a longitudinal crest: in modesta
the ductus is broader, the base of the bursa sclerotised, somewhat hooked,
and the spines are not concentrated into a forest.
Holotype .SARAWAK: Gunung Mulu Nat.
Park, R.G.S. Exped. 1977-8 (J.D. Holloway et al.) Site 14, January, Camp
2.5, Mulu 1000m. 413461, [lower montane forest], BM geometrid slide
19016.
Paratypes: 1 (slide 19004) as holotype but Site 3, January, Camp 4, Mulu 1780m,
453463; 1 (slide 19015) SABAH: Bundu Tuhan, 1200m, vii-ix-1965Cambridge
Expedition to Mt Kinabalu 1965 (H.J. Banks, H.S. Barlow & J.D. Holloway);l (slide 19005) SABAH: Mt Kinabalu, Kamborangoh, 2110m, general data as
previous; 1 (slide 19006) SABAH: Mt Kinabalu, 5500ft,23-24.1.1976 (E.W.
Classey) ; 2 (prep. 6467) SABAH (N. Borneo): Env. de Ranau, Kundasang,
1200m 1 /2.iii.1987 (C.Herbulot) (Colln Herbulot).
Geographical range. Borneo.
Habitat preference. The species has been taken in both lower and upper
montane zones over an altitude range of 1000m to 2110m. Only dissected material
is given type status.
7-8mm. This species resembles B. modesta Warren but is
much paler, the male lacking the strong white fleck between the angles of the
forewing postmedial. The male costa is only weakly bowed and lacks any scale
crest. The fasciation is neat and regular, darker brown on the pale brown
ground, the angles of the postmedials rather rounded, with a paler edging
distally. The aedeagus is larger, tapering more from a bulbous base. The
octavals are simple, separate, apically acute, whereas in modesta they
form a broadly triangular plate, apically convergent and bilobed. The female
genitalia have short, narrow ductus and a large, pyriform bursa more or less
full of delicate spining that is more concentrated in a longitudinal crest: in modesta
the ductus is broader, the base of the bursa sclerotised, somewhat hooked,
and the spines are not concentrated into a forest.