Stigmella altiplanica Diškus & Stonis, sp. nov.

(Figs 18, 27, 98–102)

Type material. Holotype: Ƌ, PERU, Dept. Ancash, 35 km SE Huaraz, Cerro Cahuish, 9°40'50"S, 77°13'32"W, 4100 m, Quabrada Pucavado, 15–18.ii.1987, O. Karsholt, genitalia slide no. AD647Ƌ (ZMUC).

Diagnosis. The combination of a set of four large cornuti with a cluster of small spine-like cornuti, squareshaped uncus, and speckled, 4.5 mm long forewing distinguishes S. altiplanica sp. nov. from all other Stigmella species.

Male (Figs 98, 99). Forewing length 4.5 mm; wingspan about 9.5–9.6 mm. Head: palpi brownish cream; frontal tuft comprised of cream and fuscous brown piliform scales (fuscous scales prevail); collar cream; scape cream with few pale grey-brown scales; antenna slightly longer than half the length of forewing; flagellum with 40 segments, dark grey, glossy. Thorax pale grey-brown with golden gloss; tegula grey-brown to fuscous brown with golden gloss. Forewing golden cream speckled with brown and fuscous brown scales; most of fuscous scales with distinctive blue or purple iridescence; fascia absent; fringe pale brown to brown; underside of forewing greybrown. Hindwing pale brown on upper side and underside, with no spots or androconia; its fringe pale brown.

Female. Unknown.

Male genitalia (Figs 100–102). Capsule longer (390 µm) than wide (240 µm). Vinculum with rounded lateral lobes and long ventral plate. Uncus square-shaped, divided into two wide angular lobes. Gnathos with two long and slender caudal processes and small central plate. Valva 265–270 µm long, 80–85 µm wide, with one pointed apical process and sinuous inner lobe; transtilla with short pointed sublateral processes. Juxta membranous, indistinctive. Phallus (Fig. 101) 355–360 µm long, 90–95 µm wide; vesica with a set of four large cornuti and a basal cluster of numerous small spine-like cornuti.

Bionomics. Adults fly in February. Otherwise biology unknown.

Distribution (Figs 18, 27). This species occurs high in the Peruvian Andes (Peru: Ancash Departamento) at altitudes about 4100 m.

Etymology. The species name is derived from Spanish Altiplano (high plain) in reference to the high altitude occurrence of the new species.