Stigmella ageratinae Diškus & Stonis, 2016

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 : 75-79

Stigmella ageratinae Diškus & Stonis , sp. nov.

( Figs 20, 25–28, 213–229)

Type material. Holotype: ♀, BOLIVIA, Copacabana (southern shore of Lake Titicaca), 16°09'42"S, 69°05'19"W, elevation 3930 m, mining larvae on Ageratina pentlandiana (DC.) R.M. King & H. Rob., 28.iv.2014, ex pupa v.2014, field card no. 5171, A. Diškus, genitalia slide no. AD 596♀ ( ZMUC) . Paratype: 1 Ƌ [from mature pupa], same label data as holotype, genitalia slide no. AD595Ƌ (ZMUC).

Diagnosis. The combination of a golden cream forewing with fuscous markings, bilobed uncus, closely juxtaposed processes of gnathos, and specific set of large horn-like cornuti distinguishes S. ageratinae sp. nov. from all other Stigmella species. The host-plant Ageratina pentlandiana ( Asteraceae ) also makes this species highly distinctive.

Male. Similar to female; known only from mature pupa.

Female ( Figs 213, 214). Forewing length about 2.4 mm; wingspan 5.5–5.6 mm. Head: palpi greish white to grey, glossy; face golden cream; frontal tuft fuscous centrally, golden cream to ferruginous cream laterally; collar large, golden cream; scape golden cream; antenna slightly longer than half the length of forewing; flagellum with 23–24 segments, fuscous glossy on upper side, yellowish cream to grey cream on underside. Thorax golden cream; tegula fuscous, distally golden cream. Forewing golden cream, with a few scattered fuscous scales and with fuscous ill-defined oblique median fascia, and fuscous apex; all fuscous markings with little or strong purple iridescence; fringe grey to blackish grey, with some overlapping greyish cream lamellar scales and golden cream piliform scales; underside of forewing dark grey to fuscous, without spots or androconia. Hindwing and its cilia pale grey to fuscous grey on upper side and underside, with no spots or androconia; its fringe pale grey. Legs golden cream to brownish cream, darkened with grey on upper side. Abdomen dark grey, glossy on upper side, grey crean on underside; tufts short, grey cream to cream; genital segments cream.

Male genitalia ( Figs 215–220). Capsule longer (260 µm) than wide (190 µm). Uncus with two caudally tapering lobes. Gnathos with two closely juxtaposed caudal processes, small central plate and large, triangular lateral lobes. Valva 170–180 µm long, 55–70 µm wide, with two apical processes; transtilla with widely rounded corners, without sublateral processes. Juxta membranous, indistinctive. Vinculum with short ventral plate and without lateral lobes. Phallus ( Figs 217, 219) 140 µm long, 70–75 µm wide, with slender spines apically; vesica with many large horn-like cornuti gathered in a narrow band.

Female genitalia ( Figs 212–223). Total length about 530 µm. Anterior and posterior apophyses almost equal in length. Vestibulum without sclerites. Corpus bursae about 320 µm long, with little folded distal part and narrow basal part with comb-like pectinations; signa absent. Accessory sac small; ductus spermathecae with an irregularly shaped sclerite. Abdominal tip narrowing and rounded distally.

Bionomics. (Figs 224–229). Larva mines in leaves of Ageratina pentlandiana (DC.) R.M. King & H. Rob. ( Asteraceae ) (Figs 224, 226). Larva pale yellow with indistinct intestine and dark brown head; mines in April. Leaf-mine as a gallery strongly contorted in distal third (therefore resembling a blotch) ( Figs 2 27–229). Blackbrown to black frass gathered into a wide central line with wide margins of the gallery remaining unfilled. Larval exit slit on upper side of the leaf. Cocoon beige to pale beige; length 2.5–2.7 mm, maximum width 1.5–1.6 mm.

Distribution ( Figs 20, 25–28). This species occurs in the Altiplano of the Bolivian Andes ( Bolivia: southern shore of Lake Titicaca) at altitudes about 3930 m.

Etymology. The species is named after the host-plant genus Ageratina Spach ( Asteraceae ).