Stigmella maya Remeikis & Stonis

Stonis, Jonas R., Remeikis, Andrius, Diškus, Arūnas & Noreika, Remigijus, 2013, New Nepticulidae species (Insecta: Lepidoptera) from the Yucatán Peninsula (SE Mexico), Zootaxa 3609 (2), pp. 223-230 : 224

Stigmella maya Remeikis & Stonis , sp. nov.

( Figs 2–10 , 15–16 )

Type material. Holotype: 3, MEXICO, Yucatán, Quintana Roo, Tulum, 20°12'35"N, 87°25'55"W, elevation 15 m, mining larvae 29.xi.2011, ex pupa 11.xii. 2011, leg. A. Remeikis & J.R. Stonis, gen. slide no. RA 473. Paratypes: 23, 3Ƥ, same label data, ex pupae 8–16.xii.2011, gen. slide nos RA 4723, RA 469Ƥ, RA 470Ƥ, RA 471Ƥ (all specimens of the type-series are currently deposited in LEUS, with further re-deposition at ZMUC).

Diagnosis. A very distinctive, very small dark-winged species with a silver-white fascia in the forewing. Externally, males of the new species easily distinguished from all other currently known Stigmella species, including Neotropical ones, by black hindwings densely covered with androconial scales. In male genitalia, S. maya differs from all Neotropical Stigmella species by a combination of a specialized uncus, a broad U-shaped gnathos and a simple apically pointed valva.

Male ( Figs 2, 4 ). Forewing length 1.4–1.5 mm; wingspan 3.04–3.27 mm (n=3). Head: palpi cream; frontal tuft cream, on vertex brown to orange; collar and scape whitish to cream; antenna with 23–24 segments, slightly longer than half forewing; flagellum brown-grey to cream-glossy (particularly first 8 segments) on upper side, cream on underside. Thorax fuscous grey; tegulae black. Forewings fuscous grey, speckled in apical part, with silver-white slightly shiny fascia; terminal cilia white, comprised of broadened (lamellar) scales; tornal cilia blackish grey, comprising piliform scales ( Fig. 2 ); underside of forewing black. Hindwings fuscous grey, densely covered with black androconia, except at apex ( Fig. 4 ); cilia of hindwings blackish grey. Legs dark cream to black on upper side, dark cream on underside. Abdomen black on upper side, dark grey, with purple and some green iridescence on underside; anal tufts white-cream.

Female ( Figs 3, 5 ). Forewing length 1.3–1.4 mm; wingspan 2.8–3.0 mm (n=3). Hindwings grey to blackish grey; no androconial scales. Abdomen shiny black on upper side, grey on underside, without purple and green iridescence. Otherwise as male.

Male genitalia ( Figs 6–9 ). Capsule longer (215 mm) than wide (160 mm) (n=2). Vinculum with two large lateral (anterior) lobes. Uncus with small heavier sclerotised lateral (posterior) lobes ( Fig. 7 ). Gnathos narrow, broadly U-shaped, posterior projections far apart ( Fig. 7 ). Valva ( Figs 6, 9 ) 130 mm (n=2) long, basally broad, narrowed apically, with thickened and pointed apical process; transtilla with short triangular pointed sublateral processes. Aedeagus ( Fig. 8 ) 230 mm (n=2); vesica with numerous minute cornuti.

Female genitalia ( Fig. 10 ). Total length 575–585 mm (n=3). Vestibulum relatively broad, without sclerites. Corpus bursae broadly oval, very large, covered with numerous pectinations, without signa. Ductus spermathecae with 2.5 large convolutions.

Bionomics. Mines in leaves ( Fig. 16 ). Host-plant: Karwinskia humboldtiana (Schult.) Zucc. (Rhamnaceae) ( Fig. 18 ). Egg on upper side of the leaf. Larvae mine in late November and early December. Contorted or sinuous gallery of mine filled with dark brown to blackish frass ( Fig. 16 ). Larva pale green to green, with dark green intestine. Larval exit slit on upper side of the leaf. Cocoon very pale brownish cream to grey-beige; length 1.4 – 1.75 mm, maximal width 0.7–1 mm (n=6). Adults emerged in December.

Distribution ( Fig. 1 ). Lowland coastal forest of Yucatán (SE Mexico: Quintana Roo) ( Fig. 15 ).

Etymology. This species is named after the Maya people, a Mesoamerican civilization.

Figures

FIGURES 1 – 5. Nepticulidae of Yucatán and adjacent areas. 1, currently known distribution: 1. Stigmella maya, Acalyptris yucatani. 2. Enteucha hilli, E. contracolorea, Stigmella barbata, S. kimae, S. albilamina, S. fuscilamina, S. pruinosa, Ectoedemia sp. 29105, E. fuscivittata, Fomoria diskusi, F. sp. 29122, Acalyptris latipennata, A. dividua, A. bovicorneus, A. martinheringi, A. hispidus, A. novenarius, A. bifidus, A. trifidus, A. unicornis, A. laxibasis, A. sp. 29135, A. platygnathos, A. sp. 29140, Glaucolepis argentosa. 3. Enteucha snaddoni, Acalyptris fortis. 4. Manoneura basidactyla. 5. Acalyptris lascuevella. 6. Stigmella racemifera, S. sp. 0 18, Acalyptris paradividua, A. terrificus, A. sp. 0 15, A. sp. 0 16. 7. Stigmella plumosetaeella (Map — courtesy of T. Patterson, USA); 2, adult of Stigmella maya sp. nov., male; 3, female; 4, male, hindwing with black androconia; 5, female. Scale bar 1 mm.

FIGURES 6 – 10. Genitalia of Stigmella maya sp. nov. 6, capsule of male genitalia, holotype, gen. slide no. RA 473. Scale bar 50 mm; 7, uncus and gnathos, holotype, gen. slide no. RA 473. Scale bar 10 mm; 8, aedeagus, holotype, gen. slide no. RA 473. Scale bar 50 mm; 9, valva, holotype, gen. slide no. RA 473. Scale bar 25 mm; 10, female genitalia, paratype, gen. slide no. RA 470. Scale bar 100 mm.

FIGURES 15 – 19. Bionomics. 15, type locality and habitat of Stigmella maya sp. nov. and Acalyptris yucatani sp. nov., Yucatán, Tulum, 20 ° 12 ' 35 " N, 87 ° 25 ' 55 " W, elevation 15 m; 16, leaf-mine of Stigmella maya sp. nov., with mining larva; 17, empty leaf-mine of Acalyptris yucatani sp. nov.; 18, Karwinskia humboldtiana (Rhamnaceae), a host-plant of Stigmella maya sp. nov.; 19, Schinus sp. (Anacardiaceae), a host-plant of Acalyptris yucatani sp. nov.