Orthonevra gewgaw ( Hull, 1941 )

Miranda, Gil F. G., Soares, Matheus M. M. & Thompson, Christian, 2024, The Neotropical Orthonevra Macquart, 1829 (Diptera: Syrphidae), Zootaxa 5484 (1), pp. 1-78 : 28-31

Orthonevra gewgaw ( Hull, 1941)

Chrysogaster gewgaw Hull 1941: 152 , fig (wing). Type-locality: Cuba, Soledad (HT male MCZ). Fluke 1957: 49 (catalog citation).

Orthonevra gewgaw : Thompson 1981: 142, fig (male genitalia) ( Cuba, diagnostic note); Thompson et al. 1976: 91 (Catalog citation); Thompson 2006: 121 (catalog citation), 21 (key reference).

98-5. Thompson 2006: 22 (key reference)

Figs 13 and 14 . Map: Fig. 40

Redescription. MALE. Head ( Fig. 13d–f ): metallic green except blue on smooth area, face with convexity on dorsal ½ and ventral ¼ slightly produced anteriorly as a convexity, regulose except smooth medially between convexity and anterior oral margin and with weak transverse striae on convexity, pile white and narrowly scale-like, and with a regular row of pile laterally following the eye margin; with white microtrichose subtriangular macula laterally, positioned immediately ventral to level of antennal base but far removed from it. Antenna dark, scape and pedicel yellow ventrally; pedicel twice the length of the scape, postpedicel oval elongated, 1.5 × the length of the pedicel. Mala produced apico-ventrally, smooth. Gena shiny, smooth, and with white pile. Frontal triangle shiny, rugose, with very sparse white pile medially but with a distinct row laterally following eye margin. Vertical triangle isosceles-shaped, 2 × the length of the eye contiguity, metallic green, with short, erect pale and dark pile on ocellar triangle and posterior to it; ocellar triangle equilateral, taking up 2/3 of the vertical triangle. Occiput not visible laterally on dorsal ½, ventral ½ uniformly covered with white microtrichia, with a row of short dark pile that becomes longer and white close to the gena. Eyes holoptic; with a strongly sinuous sub-anterior and middle vittae, and a complete medial fascia, posterior margin dark on ventral ½.

Thorax ( Fig. 13d, e ): metallic green, homogeneously covered in short, erect, white pile; scutum with four complete and separate dark matte vittae, that taper anteriorly, sub-medial vittae slightly interrupted at transverse sulcus, and with a short narrow lateral vittate macula posterior to transverse sulcus, and an additional, anteriorly tapering, dark sub-lateral vitta posteriorly between sub-medial vitta and lateral vittate macula; scutellum metallic bluish-green but with a semi-circular matte dark area medially, with short, erect, white pile. Pleuron covered in fine microsculpturing but smooth on proepimeron, anterior anepisternum and posterior anepimeron, with short white pile on antepronotum, proepisternum, posterior anepisternum, on dorsal and ventral patches on katepisternum, anterior anepimeron, metasternum and katatergum, white microtrichose on antepronotum and dorsally on anterior anepisternum. Calypter white, except margin dark, with white marginal pile, ventral lobe with longer and darker marginal pile. Plumule white and long. Halter yellowish.

Legs ( Fig. 13e ): metallic bluish-green, except brownish tibiae, and tarsi with first two tarsomeres yellow, remaining brown. Legs covered with short white pile, with black ventral setulae on mesotarsus, metafemur, and apex of mesotibia, shorter, paler and sparser laterally on pro and metatarsus.

Wing ( Fig. 13e ): hyaline, with dark vitta sub-apically (from end of R2+3 until posterior end of M1), and faintly on dm-m, a small dark spot at the end of r2+3, medially on r2+3, a fasciate macula medially on cell r1 (slightly basal to the end of R1), a fasciate pair apically on r4+5 and a small fasciate one antero-apically on dm ( Fig. 13b ), microtrichose except bare immediately posterior to pseudovein; basicosta with dense appressed pale to dark pile, with two more prominent black setae apically. Alula 2 × the width of cell c.

Abdomen ( Fig. 13d, e ): metallic blue, apex of terga matte black microtrichose sub-laterally, tergum 4 mostly matte medially, pile sockets as small protuberances, pile white, appressed and very short laterally, except black medially, longer and erect laterally on tergum 1 and 2; sterna metallic green, with longer white appressed pile; sternum 4 with right side slightly longer than left.

Genitalia ( Fig. 14c–e ): Epandrium narrow baso-apically; surstylus bent in a 90° angle at basal 1/3, with a rounded apex directed apically, and very sparse inconspicuous pile ( Fig. 14e ); subepandrial sclerite arms bend laterally to reach the base of surstyli; cercus triangular, directed apically, and with a slightly concave base, with distinct long pile. Hypandrium slightly compressed on apical ½, with anterior ventral notch through almost ½ the length of the hypandrium, V-shaped, notch with a short lamina on each side; postgonites irregular, with a wider base homogeneously pilose, and a bare short finger-like projection at the apex; phallus beak-like apically, widened medially, although slightly convex medio-ventrally, not forming prongs, basal tubular process directed slightly apically.

FEMALE ( Figs 13a–c , 14a, b ). Like male except: head metallic green, face with slight convexity in profile; scape and pedicel can be mostly yellow; frons with medial longitudinal sulcus starting anterior to the ocellar triangle and extending throughout 3/4 of the length of the frons, with more homogeneously distributed pile; vertex small, metallic green; ocellar triangle equilateral, occupying most of the vertex; occiput not visible laterally on dorsal 1/3, ventral 2/3 homogeneously covered in white microtrichia which gets longer dorsal to the gena, pile becomes very short and inconspicuous medially; eyes sub-anterior vitta may be straight dorsally, middle fascia varies from complete to absent; scutellum may be wholly metallic; legs metallic reflections mostly green; tibiae can be mostly yellowish; abdominal matte areas inconspicuous; tergum 5 wholly metallic. Genitalia ( Fig. 14a, b ): Tergum 7 as two rectangular sclerotized areas, with few pile on apical margin. Sternum 7 as a sclerotized strip with pile on apical margin. Tergum 8 rectangular, with a deeply concave basal margin, with a pair of pile on each side of the concavity. Sternum 8 large, heart-shaped, apical margin with short medial ‘V-shaped’ indentation, wholly pilose. Sternum 9 sub-triangular, lightly sclerotized. Epiproct as two quadrate sub-rectangular sclerotized areas, with two short baso-lateral apodemes, pilose on apical 1/3 and more so on membranous area in between. Cercus semi-oval, wholly pilose, positioned ventro-laterally to epiproct. Hypoproct mostly membranous, with medial pigmented area, pilose medially.

Length. Body 4.53–4.79mm (n=2), wing 3.54–4.32mm (n=4); female 4.64–5.70mm (n=3), wing 3.64–4.64mm (n=4).

Distribution. Cuba, Dominican Republic and Puerto Rico ( Fig. 40 )

Altitudinal range. 90–1580m.

Comments. Orthonevra gewgaw is restricted to the islands of the Greater Antilles of the Caribbean region. Orthonevra gewgaw , O. nitida and O. nitidula are the only species with an extra vittate macula on the scutum between the narrow lateral vittate macula and the long sub-medial vitta.

Type material examined: CUBA. Soledad , Geo. Salt, 27.v.1925 (photo, male holotype gewgaw MCZ ) .

Additional material examined: CUBA. Santa Clara Prov. [sic], Soledad , 9–16.vi.1939, C. T. Parsons (1 male and 1 female on the same pin CNC, CNC _ Diptera 238725) . DOMINICAN REPUBLIC. La Vega, Constanza (ca 16km SE), 1580m, 18°50.6’N 70°40.7’W, 15.v.1998, W.N. Mathis (2 males USNM, USNMENT00086766– 7 ) ; Independencia, Puerto Escondido , 1370m, 18°19.6’N 71°35’W, 24.iii.1999, W.N. Mathis (1 male USNM, USNMENT00089812 ) . PUERTO RICO. Ciales [ca 18°19'59.8"N 66°28'47.0"W], 2mi S Florida , 25–31.i.1984, E.A. Lisowski [9 females CSCA, CNC909823 (only one female labeled)] .

Figures

FIGURE 13. Orthonevra gewgaw (Hull, 1941). a–c. Female: a. Habitus dorsal. b. Habitus lateral. c. Head, oblique lateral. d–f. Male: d. Habitus dorsal. e. Habitus lateral. f. Head, oblique lateral view.Abbreviations: fm: fasciate maculae; lvm: lateral vittate macula; sav: sub-anterior vitta; sc: scale-like pile; slv: sub-lateral vitta; mve: medial vitta (eye).

FIGURE 14. Orthonevra gewgaw (Hull, 1941), genitalia. a. Female, dorsal view. b. Female, ventral view. c–e. Male: c. Hypandrium, lateral view (postgonite focused). d. Hypandrium, lateral view (phallus focused). e. Epandrium, lateral. Abbreviations: btp: basal tubular process; cerc: cercus; epi: epiproct; hypo: hypoproct; pg: postgonite; ph: phallus; sur: surstylus; s8: sternum 8; t8: tergum 8.

FIGURE 40. Distribution map for Orthonevra gewgaw (Hull, 1941), O. gouletmasnerorum sp. nov., O. minuosetulata sp. nov., O, nebulosa sp. nov., O. neiae sp. nov., O. neotropica (Shannon, 1925), and O. theta sp. nov.