Adult wingspan 11.5?13.5 mm. Head blackish brown， with metallic sheen， smoothly scaled； neck with yellow scales， like a necklace. Labial palpus with basal segment shining white； second and third segments blackish brown except cream white on dorsal surface of second segment； third segment almost as long as second segment， acute at apex. Antenna (Fig. 6) black， with bluish metallic hue， 3/5 length of forewing； flagellum with basal half thickened by moderately raised scales on posterior margin. Haustellum with whitish yellow scales basally. Collar， thorax and tegula blackish brown， with greyish metallic hue， tinged with some ochreous yellow scales； metathorax ochreous yellow medially. Forewing narrowly elongate， lanceolate， basal 2/3 uniformly wide， distal 1/3 narrowed to acute apex； blackish brown， with metallic hue； with four equally large orange yellow spots: costal margin with a spot at distal 1/4， cell with a spot at basal 2/5， sometimes crossing fold posteriorly， dorsum with a spot at basal 1/3 and end of fold respectively； cilia blackish brown. Hindwing and cilia dark brown， cilia tinged with yellow basally. Legs blackish brown except fore- and mid femora and tibiae creamy white on dorsal surface. Abdomen: dorsal surface blackish brown with copper and purplish metallic hue except ochreous yellow from fourth to seventh segment in male (Fig. 3a)， from fifth to seventh segment in female (Fig. 3b)； ventral surface yellow tinged with brown. Male genitalia (Fig. 10): Uncus strongly sclerotized， almost 3 times as long as tegumen； basal 1/3 fused， subquadrate； distal 2/3 bilobed， straight， with dense setae along lateral margins； each lobe with basal 2/3 uniformly wide， distal 1/3 narrowed to rounded apex. Gnathos arm broad-banded， H-shaped； distal process wide and weakly sclerotized basally， narrowed and more sclerotized distally， abruptly narrowed and beak-like from before apex to pointed tip， curved ventrad before apex. Tegumen narrowed posteriorly， mostly wider anteriorly， deeply concaved in broad V-shape on anterior margin. Valva straight， claviform， elliptically dilated and with dense setae distally， rounded apically， sparsely setose basally， approximately 1.5 times length of uncus. Vinculum very narrow， Yshaped， extending to before apex of saccus by two straight narrow folds. Saccus elongate triangular， as long as uncus. Phallus slightly longer than valva， strong， pointed apically.