Stigmella nivea Remeikis & Stonis

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 : 63-66

Stigmella nivea Remeikis & Stonis , sp. nov.

( Figs 20 , 27 , 180–185 )

Type material. Holotype: 1 Ƌ, PERU, Dept. Puno, 85 km W Puno, Cerro Huajrapata , 6.iv.1987, 4700 m, O. Karsholt, genitalia slide RA 700 male ( ZMUC).

Diagnosis. This relatively small species differs from other Stigmella species, including Andean species, in the specific shape of gnathos with single very large caudal process (see fig. 184) and elaborated central plate. The irregularly scattered grey-white scales on grey forewing apex are also highly diagnostic.

Male ( Figs 180, 181 ). Forewing length about 2.5 mm; wingspan about 5.4 mm. Head: palpi grey; frontal tuft fuscous brown, with a few brownish cream piliform scales on vertex; collar and scape brownish cream; antenna slightly shorter than half the length of forewing; flagellum with 28 segments, dark grey with golden gloss on upper side and underside. Thorax and tegula grey with little golden gloss and little purple iridescence. Forewing grey with little golden gloss, and with scarse grey-white scales irregularly scattered over forewing apex; fringe grey, whitish grey distally; underside of forewing dark grey with little purple iridescence, without spots. Hindwing grey to pale grey on upper side and underside, without spots or androconia; fringe grey. Legs glossy, dark grey;at certain angle of view—silvery grey, with little purple iridescence.

Female. Unknown.

Male genitalia ( Figs 182–185 ). Capsule significantly longer (330–335 µm) than wide (195 µm). Uncus long, with two lobes. Gnathos with large caudal process and elaborated central plate. Valva 205–210 µm long, 50–55 µm wide, with two small apical processes; transtilla without sublateral processes. Juxta membranous, caudally triangular and stronger thickened. Vinculum with small pointed lateral lobes, and short ventral plate. Phallus ( Fig. 185 ) 420 µm long, 65–95 µm wide; vesica with numerous large spine-like cornuti gathered into a large band.

Bionomics. Adults fly in April. Otherwise biology unknown. The holotype was swept from the vegetation during early afternoon between light snow flurries.

Distribution ( Figs 20 , 27 ). This species occurs in the high Peruvian Andes ( Peru: Puno Departamento) at altitudes about 4700 m.

Etymology. The species name is derived from Latin niveus (snowy, of snow, snow-white) in reference to the irregularly scattered grey-white scales on forewing apex (like melting snowflakes on grey background). It should be also mentioned, that this amazing new species occurs close to the Andean snowline.

Figures

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

FIGURES 20 – 21. Distribution of high altitude Stigmella in the Altiplano (Peru and Bolivia). 20, distribution map; 21, the Altiplano in Bolivia (by A. Diškus).

FIGURES 180 – 185. Stigmella nivea Remeikis & Stonis, sp. nov., holotype. 180, 181, male adult; 182, 183, male genitalia, slide no. RA 700, capsule with phallus removed; 184, same, gnathos; 185, same, phallus (ZMUC).