(Figs. 24, 48, 60)

Description. Adult (Fig. 24): Wingspan 16.5–19.0 mm. Head with frons white, vertex deep-yellow, scale tuft behind compound eye yellow except black posteriorly. Antenna whitish-yellow except scape black and flagellum ringed with black dorsally. Labial palpus grayish-white, third segment dark-brown in distal half. Thorax whitishyellow, yellow along margin. Tegula grayish-yellow, with black scales on outer and inner margins. Forewing whitish-yellow, overlaid with brown spots and patches, yellow along fold, predominantly brown posteriad of fold; rounded black spot at end of cell; large black patches at base of costal margin and dorsad of fold to tornus; several longitudinal pale-brown streaks along veins from before anterodistal corner to ventrodistal corner along outer margin of cell; terminal line dark-brown; cilia whitish-yellow, mottled black scales on termen. Hindwing and cilia yellowish-brown. Legs dirty whitish-yellow.

Male genitalia (Fig. 48): Brachia of uncus broad at base, narrowed to 3/5 where it curved slightly inward; distal 2/5 narrow, elongate elliptical. Valva broad and short, elliptical, with numerous commalike processes on ventral half, ventral margin with fine setae; valvella strong, longer than valva, sparsely setose, dilated distally, apex round, with a setose process from base reaching 2/3 length. Phallus very long, more than three times length of uncus brachium, evenly wide, weakly sclerotized; cornutus absent.

Female genitalia (Fig. 60): Posterior apophysis about twice as long as anterior apophysis. Sterigma tubular, parallel sided laterally, posterior margin obliquely truncate. Ductus bursae longer than twice length of anterior apophysis; ductus seminalis arising from about middle of ductus bursae. Corpus bursae large, elongate oval, slightly shorter than ductus bursae; signa a pair of longitudinal sclerotized leaf-shaped plates, about 1/5 length of corpus bursae.

Type material. Holotype ♂, BRUNEI: Rampayoh R. [4°29' N, 114°29' E], LP 291B, GR 951801, Lowland dipterocarp forest, 150 ft., 11–15.iv.1988, coll. G. S. Robinson, BM 1988-160, BMNH Microlep. slide no. 31000, Houhun Li (BMNH, London).

Paratypes: 4 ♂, 1 ♀, same data as for holotype, BMNH Microlep. slide no. 31001 (♀), Houhun Li (BMNH, London).

Distribution. Brunei.

Diagnosis. This new species is similar to S. chionoscia Meyrick in the male genitalia, but can be separated from it by the valva having numerous commalike processes on ventral half and the valvella with a setose process arising from base in the male genitalia; the tubular sterigma obliquely truncate on posterior margin and the signa being a pair of sclerotized longitudinal leaf-shaped plates in the female genitalia. In S. chionoscia Meyrick, the valva has commalike processes throughout the ventral surface and the valvella lacks the process (Fig. 43); the sterigma is cone-shaped and the signa are a pair of fan-shaped plates (Fig. 56). The new species is also similar to S. incantata Meyrick, but can be distinguished by the tegumen being slightly concave on the anterior margin, whereas S. incantata has the margin deeply concave and trianglar (Fig. 44).

Etymology. The specific epithet is derived from the Latin gibbosus = gibbous, in reference to the valvella with a setose process in the male genitalia.