Stigmella emarginatae Diškus & Stonis, 2016

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, Zootaxa 4136 (1), pp. 101-128 : 104-107

publication ID	https://doi.org/ 10.11646/zootaxa.4136.1.4
publication LSID	lsid:zoobank.org:pub:BBC55637-6919-43B3-BB85-83E2AFFE2CED
DOI	https://doi.org/10.5281/zenodo.6070503
persistent identifier	https://treatment.plazi.org/id/03B47A7D-FFFA-A12C-D7C1-41BDAD08FA8F
treatment provided by	Plazi
scientific name	Stigmella emarginatae Diškus & Stonis
status	sp. nov.

Treatment

1. Stigmella emarginatae Diškus & Stonis View in CoL , sp. nov.

( Figs. 3–19 View FIGURE 3 View FIGURES 4 – 10 View FIGURES 11 – 14 View FIGURES 15 – 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 View FIGURES 4 – 10 ). 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 View FIGURES 4 – 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 View FIGURES 11 – 14 View FIGURES 15 – 19 ). 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 View FIGURES 11 – 14 ). Gnathos 115–120 µm long, with two caudal processes ( Figs 14 View FIGURES 11 – 14 ); central plate of gnathos large, 85–90 µm broad. Valva ( Figs 11, 13 View FIGURES 11 – 14 ) 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 View FIGURES 11 – 14 , 18 View FIGURES 15 – 19 ). Juxta membranous, usually indistinct ( Fig. 11 View FIGURES 11 – 14 ). Phallus ( Fig. 12 View FIGURES 11 – 14 ) 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 View FIGURES 11 – 14 , 15–17 View FIGURES 15 – 19 ); no small spine-like cornuti developed.

Female genitalia ( Fig. 19 View FIGURES 15 – 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 View FIGURES 15 – 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 View FIGURES 4 – 10 ). Host-plant: Baccharis emarginata (Ruiz & Pav.) Pers. (Asteraceae) ( Fig. 5 View FIGURES 4 – 10 ). Egg on upper side ( Fig. 6 View FIGURES 4 – 10 ). 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 View FIGURES 4 – 10 ). Larval exit slit on upper side of the leaf. Cocoon greyish beige to ochre-beige ( Fig. 8 View FIGURES 4 – 10 ); 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 View FIGURE 3 ). This species occurs in the equatorial Andes ( Ecuador: Tungurahua Province) at altitudes between 1800–2000 m ( Figs 3 View FIGURE 3 , 4 View FIGURES 4 – 10 ).

Etymology. The species is named after the host-plant Baccharis emarginata .