Stigmella serpentina Diškus & Stonis, 2015

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, Zootaxa 4040 (5), pp. 576-582 : 576-580

publication ID	https://doi.org/ 10.11646/zootaxa.4040.5.6
publication LSID	lsid:zoobank.org:pub:190797A1-20DC-4242-80CC-FAE249711530
DOI	https://doi.org/10.5281/zenodo.6120032
persistent identifier	https://treatment.plazi.org/id/03F31E6D-DD0B-9D6F-FF20-F9476BA1FC63
treatment provided by	Plazi
scientific name	Stigmella serpentina Diškus & Stonis
status	sp. nov.

Treatment

Stigmella serpentina Diškus & Stonis View in CoL , sp. nov.

( Figs 1–16 View FIGURES 1 – 6 View FIGURES 7 – 13 View FIGURES 14 – 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 View FIGURES 7 – 13 ). 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 View FIGURES 7 – 13 ). 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 View FIGURES 7 – 13 ). Capsule longer (325 µm) than wide (200 µm). Vinculum usually with very small triangular lateral lobes ( Fig. 10 View FIGURES 7 – 13 ); occasionally one of these lobes can be larger than other. Uncus with two triangular caudal lobes ( Fig. 10 View FIGURES 7 – 13 ). Gnathos with two large caudal processes and very large central plate ( Figs 10, 11 View FIGURES 7 – 13 ). 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 View FIGURES 7 – 13 ). Transtilla with short transverse bar and short, triangular lateral processes (or angular, without lateral processes). Phallus ( Figs 12, 13 View FIGURES 7 – 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 View FIGURES 14 – 16 ). Total length 700 µm. Abdominal tip narrow. Accessory sac small ( Fig. 14 View FIGURES 14 – 16 ). Ductus spermathecae with one coil ( Fig. 16 View FIGURES 14 – 16 ). Corpus bursae small (about 270 µm excluding folded part) and narrow (about 100 µm) ( Fig. 14 View FIGURES 14 – 16 ).

Bionomics ( Figs 2–6 View FIGURES 1 – 6 ). Mines in leaves ( Figs 4–6 View FIGURES 1 – 6 ) of Liabum Adans. (Asteraceae) (possibly L. barclayae H. Rob. ) ( Fig. 3 View FIGURES 1 – 6 ). 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 View FIGURES 1 – 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 View FIGURES 1 – 6 ).

Etymology. The species name is derived from Latin serpentina (serpentine) in reference to the contorted leafmine.