Stigmella guatemalensis Diškus & Stonis, 2013

Stonis, Jonas R., Diškus, Arūnas, Remeikis, Andrius & Schuster, Jack, 2013, First discovery of Quercus feeding Nepticulidae (Lepidoptera) in Central America, Zootaxa 3737 (1), pp. 1-23 : 10-22

Stigmella guatemalensis Diškus & Stonis , sp. nov.

( Figs 2 , 43–45 , 81–84 )

Type material. Holotype: ♂, Guatemala, Santa Cruz del Quiché (Utatlán Ruins), 15°01'22''N, 91°10'17''W, elev. ca. 2023 m, montane forest, larva on Quercus sp., 20.ii.2012, ex pupa iii.2012, LT-GT Scientific Expedition, genitalia slide no. AD513 (ZMUC).

Diagnosis. The new species differs from other species of the quercipulchella group by the large apical process of valva, large triangular process of inner lobe of valva, very long and narrow anterior processes of gnathos, and lack of sublateral processes of transtilla. Also see Diagnosis of S. species 515.

Male ( Figs 43–45 ). Forewing length 1.8 mm; wingspan 4.0 mm. Head: palpi cream; frontal tuft dark orange; collar and scape cream; antenna with 29 segments, slightly longer than half of forewing; flagellum grey on upper side, pale grey on underside. Thorax, tegulae and forewing fuscous with distinct purple and blue iridescence; fascia of forewing postmedian, broadening at tornus, cream with distinct golden lustre; cilia fuscous; underside of forewing fully black. Hindwings fuscous grey, covered with black androconia (most overlapping over cilia) ( Fig. 44 ); cilia of hindwings blackish grey. Legs dark grey to fuscous on upper side, grey-cream on underside. Abdomen shiny, fuscous, with purple and green iridescence on upper side, silvery grey with some purple and greenish iridescence on under side; genital plates fuscous, with some purple iridescence; anal tufts fuscous, very short, indistinct.

Female. Unknown.

Male genitalia ( Figs 81–84 ). Capsule longer (255 m) than wide (190 µm). Vinculum with triangular lateral lobes. Uncus distinctly bilobed, laterally thickened ( Fig. 82 ). Gnathos with short caudal processes and very long, narrow anterior processes ( Fig. 82 ). Valva 155 µm long, with very large apical process and large triangular process on inner lobe; transtilla without sublateral processes. Aedeagus ( Fig. 84 ), 240 µm long, 120 µm broad; vesica with numerous spine-like cornuti collected into a long curved band and with an apical group of larger spine-like cornuti; manica present.

Bionomics. Mines in leaves. Host-plant: Quercus sp. (section Lobatae). Egg on upper side of the leaf. Larvae mine in February. Sinuous or contorted gallery of mine filled with blackish frass. Larva deep green, with dark green intestine. Larval exit slit on upper side of the leaf. Cocoon ochre-brown. Adults emerged in March.

Distribution ( Fig. 2 ). Known only from Guatemala in mixed montane forests at elevation about 2000 m.

Etymology. This species is named after Guatemala, a beautiful and megadiverse country from where it was found.

Stigmella species 515 ( Figs 2 , 27–29 , 85–90 )

Material examined. 1♂, 1♀, Guatemala, Panajachel, 14°45'06''N, 91°09'43''W, elevation ca. 1657 m, montane forest, larva on Quercus sp., 22.ii.2012, ex pupa iii.2012, field card no. 5108, LT-GT Scientific Expedition, genitalia slide nos AD 515♂, AD517♀ (both from developed pupae, no adult moths available) (ZMUC).

Diagnosis. It differs from the other species of the quercipulchella group by the very long and slender apical process of valva, the small triangular process on the inner lobe of the valva, very long and narrow anterior processes of gnathos, and lack of sublateral processes of transtilla. From closely related S.guatemalensis sp. nov. it differs by presence of sublateral processes of transtilla, slender apical process of valva and medially bent aedeagus. Also from S. guatemalensis sp. nov. it differs by the yellow larva and distally widened leaf-mine with thin line of frass.

Male (described from fully developed pupa). Head: palpi cream; frontal tuft orange to dark orange; collar and scape cream; antenna grey. Thorax and tegulae dark grey. Forewing fuscous with distinct purple and green-blue iridescence; median fascia of forewing silvery-white, shiny.

Female. Similar to male.

Male genitalia ( Figs 85–88 ). Capsule longer (245 µm) than wide (150 µm). Vinculum with narrow lateral lobes; ventral plate very short (35µm) ( Fig. 85 ). Uncus distinctly bilobed; lobes narrowed and chitinized caudally ( Fig. 87 ). Gnathos with two caudal processes and longer but narrower anterior processes ( Fig. 87 ). Valva 150 µm long, with very long but slender apical process, and small triangular process on inner lobe; transtilla with small slender sublateral processes. Aedeagus ( Fig. 88 ), 260 µm long, 95 µm broad, bent medially; vesica with numerous spine-like cornuti collected into a long curved band and with an apical group of larger spine-like cornuti; manica present, but very small, indistinct.

Female genitalia ( Figs 89, 90 ). Apophyses anteriores and posteriores almost equally long ( Fig. 89 ). Vestibulum narrow, without sclerites. Accessory sac heavily folded and coiled, very long (490 µm) ( Fig. 90 ). Ductus spermathecae with 3 coils. Corpus bursae weakly developed, signa absent; shape of bursae unknown (lost in genitalia slide no. AD517).

Bionomics. Mines in leaves. Host-plant: Quercus sp. (section Lobatae) ( Fig. 28 ). Egg on upper side of the leaf. Contorted gallery of mine strongly widens in distal half, with very thin line of black frass ( Fig. 27 ). Larva yellowish, with brownish intestine. Larval exit slit on upper side of the leaf. Cocoon ochre-brown. Larvae mine in February. Adults emerged in March.

Distribution ( Fig. 2 ). Known from Guatemala (mixed montane forests at elevation about 1660 m) ( Fig. 29 ).

Remark. The moth and genitalia are described from developed pupa (no pinned adults available). Therefore, the new species is left unnamed.

Figures

FIGURES 1 – 6. Major collecting localities and distribution of the species discovered in Guatemala. 1, distribution of Stigmella nigriverticella (Chambers); 2, distribution of the new Stigmella species; 3, Quetzaltenango, 14 ° 47 ' 27 " N, 91 ° 32 ' 09 " W, montane mixed forests at elevation 2500 m; 4, same, moist broadleaf tropical forest at elevation 2000 m; 5, Santa Cruz del Quiché, 15 ° 01 ' 22 '' N, 91 ° 10 ' 17 '' W, elevation ca 2020 m; 6, Panajachel, 14 ° 45 ' 06 '' N, 91 ° 09 ' 43 '' W, elevation ca. 1660 m (Maps – courtesy of T. Patterson, USA).

FIGURES 38 – 45. Adults of Stigmella species discovered in Guatemala. 38 – 40, S. lauta Diškus & Stonis, sp. nov.; 41, S. sublauta Remeikis & Stonis, sp. nov.; 42, S. aurifasciata Diškus & Stonis, sp. nov.; 43 – 45, S. guatemalensis Diškus & Stonis, sp. nov. (44, hindwing with androconial scales). Scale 1 mm.

FIGURES 81 – 84. Male genitalia of Stigmella guatemalensis Diškus & Stonis, sp. nov., holotype, genitalia slide no. AD 513. 81, general view. Scale 200 µm; 82, valvae, gnathos, uncus and transtilla. Scale 100 µm; 83, juxta. Scale 100 µm; 84, aedeagus. Scale 100 µm.

FIGURES 24 – 29. Bionomics of Stigmella species. 24, 25, S. sublauta Remeikis & Stonis, sp. nov., leaf-mines; 26, same, hostplant Quercus crassifolia Humb. & Bonpl. (section Lobatae); 27, S. aurifasciata Diškus & Stonis, sp. nov., leaf-mine; 28, same, host-plant Quercus sp. (section Lobatae); 29, same, type locality, 1660 m (Panajachel).

FIGURES 85 – 90. Genitalia of Stigmella species 515. 85, male genitalia, capsule. Scale 100 µm; 86, same, distal part. Scale 100 µm; 87, same, reconstruction. Scale 100 µm; 88, aedeagus. Scale 100 µm; 89, female genitalia, general view (with bursa copulatrix lost). Scale 400 µm; 90, same, accessory sac. Scale 200 µm.