Stigmella emarginatae Diskus & Stonis, sp. nov.
Creators: name: Stonis, Jonas R.
name: Diškus, Arūnas
name: Remeikis, Andrius
name: Davis, Donald R.
name: Solis, M. Alma
name: Torres, Nixon Cumbicus
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Nepticulidae
Stigmella
Stigmella emarginatae

description: 1. Stigmella emarginatae Diškus & Stonis, sp. nov.
(Figs. 3–19)
Type material. Holotype: ♂, ECUADOR: Tungurahua Province, Baños, 1°23'44"S, 78°26'14"W, elevation 1855 m, mining larvae on Baccharis emarginata (Ruiz & Pav.) Pers. 9.xi.2007, field card no. 4911, leg. A. Diškus, genitalia slide no. AD 600♂ (ZMUC). Paratypes: 2 ♂, 1 ♀, same locality as holotype, 10.ii.2007, 9.xi.2007, field cards nos 4850, 4911, genitalia slides nos AD 603♂, AD602♀ (ZMUC).
Diagnosis. The new species differs from all other known Neotropical Stigmella in the combination of large apical processes of the valva, 5–6 very large cornuti of the phallus, sublaterally pointed transtilla, and the large central plate of the gnathos in the male genitalia. The host-plant (Baccharis emarginata) is also distinctive for this species.
Male (Fig. 9). Forewing length 2.1–2.2 mm; wingspan 4.7–4.8 mm (n=3). Head: palpi greyish cream to cream; frontal tuft orange; collar golden brown; scape golden cream; antenna longer than half the length of forewing; flagellum with 32 segments, golden brown on upper side, greyish cream to silver cream on underside. Thorax and tegula golden brown. Forewing golden brown, with broad, distinctly postmedian fascia and slender, short apical fascia; both fasciae covered with shiny silver lamellar scales; apex of forewing golden brown, at certain angle of view with very weak purple iridescence; terminal cilia dark grey, tornal grey; underside of forewing dark brown, with no spots or androconia. Hindwing grey to pale grey on upper side and underside, with no androconia; its cilia grey-brown. Legs grey to silver on underside, darkened with fuscous on upper side. Abdomen fuscous on upper side, fuscous with metallic grey gloss on underside; anal tufts short, greyish cream; anal plates cream.
Female (Fig. 10). Flagellum with 25 segments (n=1). Postmedian fascia of forewing broader than in male. Abdomen grey to fuscous with silver gloss on upper side, metallic grey with strong silver gloss on underside; genital segments cream. Otherwise as in male.
Male genitalia (Figs 11–17). Capsule longer (340–345 µm) than wide (225–280 µm). Vinculum with short triangular lateral (anterior) lobes; ventral plate of vinculum short (54 µm). Uncus 55–65 µm broad, with two deeply divided lobes each bearing two smaller processes or papillae (Figs 11, 14). Gnathos 115–120 µm long, with two caudal processes (Figs 14); central plate of gnathos large, 85–90 µm broad. Valva (Figs 11, 13) 235–240 µm long, 85–90 µm broad, with two large apical processes; inner lobe almost straight; transtilla with pointed triangular sublateral processes (Figs 11, 18). Juxta membranous, usually indistinct (Fig. 11). Phallus (Fig. 12) 170–215 m long, 80–105 µm broad; vesica with 9–10 cornuti: 5–6 very large (30–40 µm long) and 3–4 large cornuti (Figs 12, 15–17); no small spine-like cornuti developed.
Female genitalia (Fig. 19). Total length about 640 µm. Anterior and posterior apophyses almost equal in lenght. Vestibulum broad, with weak lobe-like sclerite. Corpus bursae with large folded distal part and broader, oval shaped basal part, without signa or pectinations (Fig. 19). Accessory sac broad, short but not prominent; ductus spermathecae with one distinct (strongly chitinized) convolution. Abdominal apex blunt, rounded, about 250 µm broad.
Bionomics. Larvae mine in leaves (Figs 6, 7). Host-plant: Baccharis emarginata (Ruiz & Pav.) Pers. (Asteraceae) (Fig. 5). Egg on upper side (Fig. 6). Larvae green with dark green or brown-green intestine; mine in February and late November. Long, terminal part contorted, gallery of mine with slender central line of dark brown to black frass (Figs 6, 7). Larval exit slit on upper side of the leaf. Cocoon greyish beige to ochre-beige (Fig. 8); length 2.2–2.5 mm, maximal width 1.5 mm. Adults probably fly in March–April and December; emerged indoors in December.
Distribution (Fig. 3). This species occurs in the equatorial Andes (Ecuador: Tungurahua Province) at altitudes between 1800–2000 m (Figs 3, 4).
Etymology. The species is named after the host-plant Baccharis emarginata.
description: Published as part of Stonis, Jonas R., Diškus, Arūnas, Remeikis, Andrius, Davis, Donald R., Solis, M. Alma & Torres, Nixon Cumbicus, 2016, The first record of Baccharis L. (Asteraceae) as a host-plant genus for Nepticulidae (Lepidoptera), with description of new Stigmella species from South America, pp. 101-128 in Zootaxa 4136 (1) on pages 104-107, DOI: 10.11646/zootaxa.4136.1.4, http://zenodo.org/record/261786