Stigmella mustelina Remeikis & Stonis, sp. nov.

(Figs 18, 27, 162–166)

Type material. Holotype: Ƌ, PERU, Dept. Lima, 10 km N Oyón, Quabrada Quichas, Pueblo Quichas, 10°34'17"S, 76°46'03"W, elevation ca. 4000 m, 24–26.ii.1987, O. Karsholt, genitalia slide no. RA550Ƌ (ZMUC) . Paratype: Ƌ, same label data as holotype, genitalia slide no. AD667Ƌ (ZMUC).

Diagnosis. The combination of white spots on a pale, speckled forewing, deeply divided uncus, and specific set of cornuti which includes scattered minute cornuti and a cluster of 2–3 spine-like cornuti distinguishes S. mustelina sp. nov. from all other Stigmella species.

Male (Fig. 157). Forewing length 3.2–3.6 mm; wingspan about 6.9–7.6 mm. Head: palpi cream; frontal tuft comprised of ochreous cream and some dark brown piliform scales; collar and scape cream; antenna slightly longer than half the length of forewing; flagellum pale grey-brown. Thorax and tegula cream to grey cream, with few brown to fuscous scales. Forewing cream with some silvery gloss, sparsely speckled with grey-brown and fuscous scales, except two whitish cream subapical (dorsal and tornal) spots (sometimes merging to an ill-defined whitish cream subapical fascia); fringe pale grey to dark grey; underside of forewing grey-brown to dark grey-brown, without spots. Hindwing pale grey to dark grey on upper side and underside, without spots or androconia; fringe ochreous grey to dark grey. Legs brown cream, darkened with dark grey to fuscous on upper side. Abdomen fuscous on upper side and underside; tufts short, brownish; genital segments cream.

Female. Unknown.

Male genitalia (Figs 163–166). Capsule longer (235–370 µm) than wide (210–220 µm). Uncus with two deeply divided lobes, each with two papillae. Gnathos with two caudal processes and slender central plate; lateral arms of gnathos slender. Valva 250–260 µm long, 70–85 µm wide, with two apical processes; transtilla with very short sublateral processes. Juxta membranous, widening caudally. Vinculum with small triangular lateral lobes, very wide anterior excavation and very short ventral plate. Phallus (Figs 163, 166) 260 µm long, 80 µm wide; vesica with scattered minute cornuti and a cluster of 2–3 spine-like cornuti.

Bionomics. Adults fly in February. Otherwise biology unknown.

Distribution (Figs 18, 27). This species occurs in the high Peruvian Andes (Peru: Lima Departamento) at altitudes 4000 m.

Etymology. The species name is derived from Latin mustelina (an ermine) in reference to the whitish speckled forewing.