Material examined: 1 Ψ, Paratype, Primorskii Krai, Khasanskii rn, zap. Kedrovaya Pad’, 31.vii. 1983, Sinev; 1 Ψ, Primor’e, Khasanskii rn, zap. Kedrovaya Pad’, Seksyaeva, 1.viii. 1988, genitalia slide no. VS 289; 6 Ψ, same label, 6.viii. 1988, 2 Ψ, same label, 8.viii. 1988 [labelled in Russian]. In Coll. VPU.
Remarks. Although the type series included female paratypes, these were not discussed or illustrated.
Diagnosis. Elachista bipunctella belongs to the E. tetragonella speciesgroup sensu Kaila 1996. It is most similar to Elachista utonella Frey and E. kobomugi Sugisima, but the female genitalia are distinguished by a much larger antrum.
Female (Fig. 1). Forewing length: 3.4–4.5 mm. Wingspan: 7.3–9.6 mm. Head: frons and cervical tufts white; labial palpus white, except second segment suffused with pale brown on anteroventral surface; antennal scape white or white with few palebrown scales; flagellum pale brown or brown. Thorax and appendages white. Forewing white, with small, dark brown spot near distal end of cell and near distal end of CuP near termen (spots faint in worn specimens). Apical part of the wing white intermixed with yellowishtipped scales. Line in fringe yellowish brown. Hindwing pale greyish brown, fringe pale grey basally white apically. Abdomen white.
Female genitalia (Figs. 2–5). Papillae anales short, rounded, with few stout setae on ventral surface (Fig. 3). Apophyses posteriores slightly longer than apophyses anteriores. Antrum large, widened throughout length, bowlshaped, densely covered with internal spines, longer than papillae anales. Colliculum elongate, almost as long as apophyses anteriores. A short membranous zone between antrum and colliculum. Ductus bursae long, gradually widening from posterior end to corpus bursae. Corpus bursae slightly ellipsoid, signum narrowly elongate and spinose (Figs. 4, 5).
Distribution. Known from Far Eastern Russia, Primorskii Krai (Sinev & Sruoga 1995, 1997) and from Japan, Hokkaido (Sugisima 1999).
Biology. Host plant and early stages unknown; adults were collected from early July until early August.