Stigmella angusta Diškus & Stonis, 2016

Stonis, Jonas R., Diškus, Arūnas, Remeikis, Andrius, Gerulaitis, Virginijus & Karsholt, Ole, 2016, Leaf-mining Nepticulidae (Lepidoptera) from record high altitudes: documenting an entire new fauna in the Andean páramo and puna, Zootaxa 4181 (1), pp. 1-94 : 61

Stigmella angusta Diškus & Stonis , sp. nov.

( Figs 18 , 28 , 167–173 )

Type material. Holotype: Ƌ, PERU, Dept. Lima, 10 km N Oyón Quabrada Quichas Pueblo Quichas , 10°34'17"S, 76°46'03"W, 4000 m, 24–26.ii.1987, leg. O. Karsholt, genitalia slide no. AD633Ƌ ( ZMUC).

Diagnosis. The combination of a narrow valva, very long and narrow lateral lobes of vinculum and phallus, highly specific set of compactly assembled cornuti, and speckled forewing distinguishes S. angusta sp. nov. from all other Stigmella species.

Male ( Figs 167, 168 ). Forewing length about 4.0 mm; wingspan about 8.6 mm. Head: palpi cream; frontal tuft comprised of cream and fuscous brown piliform scales (the latter prevail); collar and scape cream; antenna distinctly longer than half the length of forewing; flagellum with 46–48 segments, grey-brown. Thorax, tegula and forewing cream (not glossy), irregularly speckled with brown and dark brown scales (few of them with weak purple iridescence); fringe pale brown; underside of forewing grey-brown, without spots. Hindwing pale brown on upper side and underside, without spots or androconia; fringe pale brown. Legs glossy cream, darkened with dark grey-brown on upper side.

Female. Unknown.

Male genitalia ( Figs 169–173 ). Capsule long (500–505 µm) but slender (200 µm). Uncus with two little deeply divided (short) lobes, each with two papillae. Gnathos with two caudal processes and slender central plate. Valva 290–295 µm long, 65–70 µm wide, with two small apical processes; transtilla with short sublateral processes. Juxta membranous, little widening caudally. Vinculum with very long and very slender lateral lobes, and short ventral plate. Phallus ( Figs 171–171 ) 405 µm long, 90 µm wide; vesica with compact clusters of 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 about 4000 m.

Etymology. The species name is derived from Latin angusta (narrow) in reference to the narrow valvae and narrow lateral lobes of vinculum in the male genitalia.

Figures

FIGURE 27. Distribution map of the high-Andean Nepticulidae with height records.

FIGURE 28. Details of adult morphology of high-Andean Stigmella, Nepticulidae.

FIGURES 18 – 19. Distribution of high altitude Nepticulidae and collecting in the Peruvian Andes. 18, distribution map; 19, collector and co-author Ole Karsholt in Polylepis forest during Polylepis Expedition organized by Prof. Dr. Jon Fjeldså (the leader of the Polylepis Expeditions, ZMUC) in 1987.

FIGURES 167 – 173. Stigmella angusta Diškus & Stonis, sp. nov. 167, 168, holotype, male adult; 169, holotype, male genitalia, slide no. AD 633, capsule with phallus removed; 170, same, focused from ventral to more dorsal view; 171, same, tube of phallus (vesica and cornuti removed); 172, 173, cornuti (ZMUC).