Stigmella serpentina Diskus & Stonis, sp. nov.
Creators: name: Stonis, Jonas R.
name: Diškus, Arūnas
name: Remeikis, Andrius
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Nepticulidae
Stigmella
Stigmella serpentina

description: Stigmella serpentina Diškus & Stonis, sp. nov.
(Figs 1–16)
Type material. Holotype: ♂, ECUADOR: Chimborazo Province, ca. 30 km NE Pallatanga, 1°52'41"S, 78°54'11"W, elevation 3025 m a.s.l., mining larva on Liabum (possibly L. barclayae H. Rob.) 21.ii.2007, field card no. 4878, leg. A. Diškus, J. R. Stonis, genitalia slide no. AD 705♂ (ZMUC). Paratypes: 1♂, 3♀, same label data as holotype, genitalia slides nos AD 615♂, AD617♀, AD704♀ (ZMUC).
Diagnosis. Externally, Stigmella serpentina sp. nov. mostly resembles S. pangorica sp. nov. S. serpentina differs from S. pangorica as having a dark collar and strong purple iridescence of the forewing. In the male genitalia, S. serpentina differs from all known Neotropical Stigmella by a single and very slender (needle-like) apical process of the valva. S. pangorica has two apical processes on each valva, and its uncus possesses four caudal lobes instead two as in S. serpentina.
Male (Fig. 7). Forewing length 2.2 mm, wingspan 4.9 mm. Head: palpi grey; frontal tuft ferruginous; collar large and fuscous, with golden gloss and purple iridescence; eye-caps golden creamy; antennae distinctly longer than half of forewing; flagellum with 41–42 segments, dark grey to fuscous on upper and underside. Thorax and tegula dark grey with golden gloss. Forewing dark grey with strong golden gloss and strong purple – blue iridescence in apical two thirds; iridescence very weak or absent in basal third. Fascia postmedian, ill-defined, almost invisible, shining golden; underside of forewing fuscous; cilia entirely dark grey-brown, with strong golden gloss, with no paler tips. Hindwing grey to dark grey, without androconia; underside fuscous; cilia grey to dark grey. Legs dark, grey-brown or fuscous. Abdomen glossy, fuscous dorsally, grey ventrally; anal tufts indistinct, very short, dark grey or fuscous; anal plates grey to dark grey.
Female (Figs 8, 9). Forewing length 2.3–2.6 mm, wingspan 5.1–5.7 mm. Collar fuscous to dark bronze with golden gloss, sometimes without purple iridescence; antennae with 30–32 segments. Forewing with purple and blue iridescence but usually, in contrast to males, with distinctive postmedian shining golden fascia; a few golden scales can be developed along tornal margin; cilia dark grey-brown to fuscous, with strong golden gloss except on tornus where golden gloss weak or absent. Abdomen dark grey-brown to fuscous and glossy both on upper and underside. Otherwise as males.
Male genitalia (Figs 10–13). Capsule longer (325 µm) than wide (200 µm). Vinculum usually with very small triangular lateral lobes (Fig. 10); occasionally one of these lobes can be larger than other. Uncus with two triangular caudal lobes (Fig. 10). Gnathos with two large caudal processes and very large central plate (Figs 10, 11). Valva 225–230 µm long, broadest at base (75–85 µm), gradually narrowing towards apex, with single and very slender (needle-like) apical process (Fig. 11). Transtilla with short transverse bar and short, triangular lateral processes (or angular, without lateral processes). Phallus (Figs 12, 13) 225–235 µm long, 80–85 µm broad; vesica with two spine-like cornuti, one of which slightly shorter than other.
Female genitalia (Figs 14–16). Total length 700 µm. Abdominal tip narrow. Accessory sac small (Fig. 14). Ductus spermathecae with one coil (Fig. 16). Corpus bursae small (about 270 µm excluding folded part) and narrow (about 100 µm) (Fig. 14).
Bionomics (Figs 2–6). Mines in leaves (Figs 4–6) of Liabum Adans. (Asteraceae) (possibly L. barclayae H. Rob.) (Fig. 3). Egg on upper side of the leaf. Larva pale greenish yellow with pale brown head; mine in February. Mine gallery contorted, with dark brown to black frass almost fully filling width of the gallery (Figs 4–6). Cocoon beige-brown; length 2.5–2.8 mm, maximal width 1.3–1.4 mm. Adults emerged in March.
Distribution. Known from a single locality in Equatorial Andes (Chimborazo Province, Ecuador). The habitat is tropical montane moist forest (Figs 1, 2).
Etymology. The species name is derived from Latin serpentina (serpentine) in reference to the contorted leafmine.
description: Published as part of Stonis, Jonas R., Diškus, Arūnas & Remeikis, Andrius, 2015, The first description of the leaf-mining Nepticulidae (Lepidoptera) feeding on the South American plant genus Liabum, Asteraceae, pp. 576-582 in Zootaxa 4040 (5) on pages 576-580, DOI: 10.11646/zootaxa.4040.5.6, http://zenodo.org/record/243312