Stigmella andina ( Meyrick, 1915 )

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 : 67-68

Stigmella andina ( Meyrick, 1915)

( Figs 18 , 27 , 186–190 )

Nepticula andina Meyrick, 1915: 255 , 256.

Stigmella andina (Meyrick) ; in Davis, 1984: 18.

Stigmella andina ( Meyrick, 1915) , in Puplesis & Robinson 2000: 24, figs 14, 88, 89, 209.

Material examined. 1 Ƌ (lectotype, designated in Puplesis & Robinson 2000), PERU, La Oroya, 12200 ft [3720 m], vii.1914, Parish, genitalia slide no. 20612 ( BMNH) ; 13 Ƌ, 6 ♀ (paralectotypes), same labael data as lectotype (genitalia slide no. 28841 (BMNH).

Diagnosis. The pale, ochreous cream or yellowish cream, male forewing (in females with purple-brown apical apex), wide, rather square valva with small, curved apical process together with 10 very large horn-like cornuti in the male genitalia distinguish this species from all other Stigmella .

Male ( Fig. 187 ). Forewing length: 2.4–2.7 mm; wingspan: 5.2–5.9 mm. Head: palpi cream; frontal tuft cream or ochreous cream to dull ochre; collar yellowish cream, indistinctive; scape cream to yellowish cream; antenna longer thank half the length of forewing; flagellum with about 34 segments, pale brown. Thorax and tegula cream with yellow-ochre tints. Forewing glossy, yellowish cream with a brassy tint (without dark scales at apex as in females but sometimes with white lustre at apex); fringe whitish cream to ochreous cream; underside of forewing pale brown, without spots. Hindwing and its fringe cream on upper side and underside, without spots or androconia. Legs pale ochreous cream to cream. Abdomen greyish brown to ochreous brown on upper side and underside, genital segments cream, distinctly contrasting in colour with rest of abdomen.

Female ( Fig. 186 ). Flagellum with about 30 segments. Apical one-quarter to one-fifth of forewing entirely covered with purple-brown scales, some overlapping on cilia. Abdomen ochreous cream to pale ochre. Ovipositor slender, well visible at end of abdomen. Otherwise as in male.

Male genitalia ( Figs 188–190 ). Capsule 370 µm long. Uncus relatively large, well-sclerotized, with four distinct caudal papillae. Tegumen with shallow caudal concavity. Gnathos with well-developed central plate and two long posterior processes; lateral arms of gnathos narrow in lateral view. Valva 208 µm, wide, with short, bent apical process, which may not be very evident in lateral view; transtilla with wide transverse bar but without sublateral processes, rounded at corners. Vinculum with pointed triangular lateral lobes. Phallus ( Fig. 190 ) 240 µm long; vesica with about 10 very large horn-like cornuti.

Female genitalia (illustrated in Puplesis & Robinson 2000: fig. 209). Total length about 1180 µm. Apophyses posteriores long (about 370 µm) and very wide, widely curved anteriorly. Apophyses anteriores slender, as long as apophyses posteriores, curved slightly inwards anteriorly. Vestibulum without sclerites. Corpus bursae with very wide and strongly folded part and larger, widely oval basal part without distinct pectinations or signa. Accessory sac wide but short; ductus spermathecae slender and slightly sinuous, without convolutions (probably with a small sclerite but spermathecae is broken in slide no. 28841 BMNH therefore sclerite is not visible).

Bionomics. Adults fly in July. Otherwise biology unknown.

Distribution ( Figs 18 , 27 ). This species occurs on the Altiplano in the Peruvian Andes ( Peru: Yauli Departamento) at altitudes about 3720 m.

Remarks. According to the original description of this species ( Meyrick, 1915), sexual dimorphism is characteristic; similar case of outstanding sexual dimorphism were repeatedly discovered by us in some other, hitherto undescribed species of the Andean Stigmella (Stonis et al., in prep.). Earlier doubts about so strongly differring male and females (can such males and females belong to the same species or represent two different species) and the recommendation that the association of S. andina males and females should be treated with caution ( Puplesis & Robinson 2000), are now rejected.

Etymology. The species name given by E. Meyrick is derived from the name of the world’s longest continental mountain range (the Andes) and in reference to the distribution of the species in the high Peruvian Andes.

Figures

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

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 186 – 190. Stigmella andina (Meyrick) (after Puplesis & Robinson 2000). 186 female adult, paralectotype; 187, male adult, lectotype; 188, male genitalia, slide no. 28841, capsule; 189, same, valva; 190, same, phallus (BMNH).