Orthonevra flukei ( Sedman, 1964 )

Miranda, Gil F. G., Soares, Matheus M. M. & Thompson, Christian, 2024, The Neotropical Orthonevra Macquart, 1829 (Diptera: Syrphidae), Zootaxa 5484 (1), pp. 1-78 : 25-27

Orthonevra flukei ( Sedman, 1964)

Chrysogaster flukei Sedman 1964: 175 , figs (male genitalia, eye, mesonotum, wing). Type-locality: U.S.A., Arizona, Cochise County (HT male UCD).

Orthonevra flukei . Thompson et al. 1976: 91 (catalog citation); Thompson 2006: 121 (catalog citation), 21 (key reference).

Figs 11 and 12 . Map: Fig. 41

Redescription. MALE. Head ( Fig. 11d–f ): metallic blue-green, face with convexity in profile and ventral ¼ slightly produced anteriorly as a convexity, regulose except smooth on ventral ¼, with sparse scale-like white pile; with white microtrichose subtriangular patch laterally, positioned immediately ventral to antennal base and separated from it. Antero-latero corners of the face slightly regulose, sparsely scale-like pilose. Antenna dark on medial-dorsal surface of pedicel and most of post-pedicel, yellow elsewhere; pedicel 3 × the length of the scape, postpedicel oval elongated, as long as pedicel. Mala produced apico-ventrally, with weak regulae. Gena shiny, smooth, and with regular white pile. Frontal triangle shiny, regulose, with a few short white scale-like pile laterally following eye margin, with median longitudinal groove. Vertical triangle isosceles-shaped, slightly longer than eye contiguity, green metallic, with long erect, white pile on ocellar triangle and posterior to it. Occiput not visible laterally on dorsal 1/3, ventral 2/3 homogeneously covered in white microtrichia, with long white pile becoming short and black on dorsal 1/3, sparse and very short black pile medially, and with longer white pile on ventral ¼. Eyes holoptic; with strongly sinuous sub-anterior and middle vittae, the ends of the former touching anterior margin and forming ringlike markings, and a medial fascia, eyes darker on anterior margin and ventrally on posterior margin.

Thorax ( Fig. 11d, e ): metallic green, homogeneously covered with very short, erect, white pile, longer on postpronotum and notopleuron; scutum with four separate dark matte vittae, sub-medial pair slightly diverging anterior to transverse sulcus, with a short narrow lateral vittate macula posterior to transverse sulcus; scutellum wholly metallic green, depressed on apical margin, homogeneously covered with pale pile. Pleuron metallic green, smooth on proepisternum, proepimeron, anteriorly on anepisternum and katepisternum, posterior anepimeron, katepimeron, and katepimeron, remaining with a coarse texture, with short white pile on antepronotum, proepisternum, proepimeron, posterior anepisternum, anterior anepimeron, on dorsal and ventral patches on katepisternum, metasternum and on katatergum, pile longer on ventral patch of katepisternum and katatergum; with some microtrichia posteriorly to posterior anepisternum and on anatergum. Dorsal lobe of calypter white with white marginal pile, ventral lobe with longer marginal pile. Plumule white. Halter yellowish.

Legs ( Fig. 11e ): metallic green, except trochanters brown and less metallic, apex of all femora, base and apex of all tibiae and all tarsomeres 1–2 yellow, remaining tarsomeres dark. Legs covered with short white pile, apex of mesotibia and mesotarsus with black setulae ventrally, metafemur ventral surface with short, black setulae.

Wing ( Fig. 11e ): hyaline, with darker vitta sub-apically (from end of R2+3 until posterior end of M1), and slight darkening anteriorly and posteriorly on vein dm-m, with two fasciate maculae on r4+5; vein C pale basally; wholly microtrichose, except anterior margin of cell cua, middle of bm and r; basicosta with dense appressed pale to dark pile, with two more prominent black setae apically. Alula large, 2 × the width of the cell c.

Abdomen ( Fig. 11d, e ): metallic green, terga 2–3 with short fasciate apico-lateral matte black maculae, pile sockets as small protuberances, pile black, appressed and very short, longer, erect and white baso-laterally on tergum 2; sterna metallic green, with longer white pile; sternum 4 right side slightly convex.

Genitalia ( Fig. 12c, d ): surstylus bent in a 90º angle at basal 1/5, crooked but mostly directed apically, with a rounded apex slightly directed ventrally, sparsely pilose ( Fig. 12c ); subepandrial sclerite arms widening slightly at apex; cercus sub-rectangular, slightly concave on anterior margin, with wide basal peduncule with an acute, curved, ventral projection, pilose ( Fig. 12c ). Hypandrium compressed medially, with anterior ventral notch, rectangular and narrow, through ½ the length of the hypandrium, notch flanked by laminae; postgonites finger-like, homogeneously covered in pile dorsally, longer baso-laterally; phallus beak-shaped apically, widened medially and ending in three prongs ventrally, basal tubular process long, directed ventrally, and ending basal to ventral prongs.

Variation. Postpedicel wholly dark, and might be slightly longer than pedicel; Sub-anterior eye vitta might touch middle vitta; also, might not form ring-markings. Tibiae can be overall paler, with just the middle darker.

FEMALE ( Figs 11a–c , 12a, b ). Like male except: mala smooth; frons strongly regulose and with median longitudinal groove ending on ventral ¼, pile scale-like and sparsely distributed throughout; eye sub-anterior vitta not strongly sinuous on dorsal half. Vertex pile shorter. Tibiae overall paler. Genitalia ( Fig. 12a, b ): Tergum 7 as two rectangular plates, with a few pile on anterior margin of each plate. Sternum 7 as a narrow rectangular plate with pile on apical margin. Tergum 8 as a rectangular plate with a strong triangular indentation on posterior margin, with two pile at the vertex of the indentation. Sternum 8 large, but not so voluminous basally, basal half sclerotized and apical half lightly sclerotized, apical margin of sclerotized portion with a V-shaped indentation, apico-lateral corners of less sclerotized portion with a shallow cavity, wholly pilose. Sternum 9 with a pair of heavier sclerotized cavities flanking the secondary gonopore, remaining of the sternum very lightly sclerotized. Epiproct as two sub-triangular plates, each plate with a short baso-lateral apodeme, pilose on apical 2/3. Cercus semi-circular, pilose, positioned ventro-laterally to epiproct. Hypoproct mostly membranous, wholly pilose.

Length. Body 4.0– 5.1mm (n=10), wing 3.3–4.1mm (n=10); female 4.11–5.78mm (n=3), wing 3.44–4.32mm (n=3).

Distribution. USA (California to New Mexico) and south to Ecuador ( Fig. 41 ).

Altitudinal range. 1140–2560m.

Comments. Costa Rican specimens were collected on Varronia curassavica ( Boraginaceae ) and Baltimora recta ( Asteraceae ). See difference with O. argentina in the ‘Comments’ of that species. Sedman (1964) studied Neotropical material of Orthonevra , but he never mentions O. argentina (or O. labyrinthops ) when he described O. flukei , so the similarities between both species were never pointed out. There is a single outlier record from Costa Rica from an altitude of 70m (EMEC1441714), but all other Neotropical records are from above 1000m.

Type material examined: USA. Arizona, Cochise County, 17 miles east of Douglas [ca 31°20’30.6”N 109°29’56.9”W] (photo, male holotype flukei UCD ) .

Additional material examined: COLOMBIA. Antioquia, El Retiro [ca 6°03’52.0”N 75°30’11.7”W] (7km N), 26.ii.1984, W. N. Mathis (1 female USNM, USNMENT01492707 ) . COSTA RICA. Guanacaste, Comelco, 8 km NW Bagaces [ca 10°31’25.7”N 85°14’55.0”W], 6.vii.1971, P. Opler (photo, 1 female, EMEC1441713); La Pacifica , 4 mi NW Cañas [ca 10°26’07.7”N 85°05’56.1”W], 4.ix.1971, P. Opler (photo, 1 female, EMEC1441714) . ECUADOR. Imbabura, Otavalo [ca 0°14’15.1”N 78°14’58.3”W], N[orth of] Perucho, 7–8.i.1971, 2000 m, L.E. Peña (10 males MZUSP) ; Loja, 4°01’54.3”S 79°13’00.4”W, 25.iv.2020 (1 female, photographic record) [https:// www.inaturalist.org/observations/43452539] . HONDURAS. Comayagua, Siguatepeque [ca 14°36’18.3”N 87°50’54.7”W], 26–27.viii.1978; J.A. Chemsak, E.G. & J.M. Linsley (photo, 1 male, EMEC1441712) . MEXICO. Durango [ca 24°03’12.7”N 104°43’03.1”W], 28 mi W Durango , 7500’, 28.vi.1964, J.F. McAlpine (1 male CNC, CNC _ Diptera 171063) ; Jalisco, Zapopan , 20°37’08.8”N 103°24’44.1”W, 28.iv.2019 (1 male, photographic record) [https://www.inaturalist.org/observations/24292114] ; Guanajuato, San Mateo Tócuaro, 19°58’07.5”N 100°43’27.1”W, 1.x.2020 (1 male, photographic record) [https://www.inaturalist.org/observations/62078130]; Zumpango, Zumpango , 19°53’03.4”N 99°07’10.4”W, 1.v.2022 (1 female, photographic record) [https://www. inaturalist.org/observations/115157826] . USA. Arizona, SW Res. Stn. Portal [ca 31°54’38.2”N 109°08’19.8”W], 8.v.1967, D.M. Wood (2 females CNC, CNC _ Diptera 171065–6); S Arizona, ??. viii.1902, F.H. Snow (1 female CNC, CNC _ Diptera 171067); Sierra Vista [ca 31°30’19.6”N 110°18’58.6”W], 4590’, 1–15.vi.1966, R.F Sternitzky (1 female CNC, CNC _ Diptera 171064); Chiricahua Mtns., Herb Martyr Campg. & Ash Spring , 5800–6100’, 31°52’N 109°14’W, 17–18.viii.2007, J. O’Hara (1 female CNC, CNC _ Diptera 11019) ; New Mexico, desert near cliff, 1365m, 32°55’44’’N 108°35’31’’W, 15.viii.2007, J. Skevington (2 females CNC, CNC _ Diptera 10702–3) ; Texas, Guadalupe Mtns. N. P., Choza spring [ca 31°54’23.5”N 104°47’11.9”W], 5300’, 13.ix.1994, J. O’Hara (1 female CNC, CNC _ Diptera 110162) .

Figures

FIGURE 11. Orthonevra flukei (Sedman, 1964). a–c. Female: a. Habitus dorsal. b. Habitus lateral. c. Head, lateral view. d–f. Male: d. Habitus dorsal. e. Habitus lateral. f. Head, lateral view. Abbreviations: pd: pedicel; ppd: post-pedicel; sav: sub-anterior vitta.

FIGURE 12. Orthonevra flukei (Sedman, 1964), genitalia. a. Female, dorsal view. b. Female, ventral view. c. Male, epandrium, lateral view. d. Male, hypandrium, lateral view. Abbreviations: btp: basal tubular process; cerc: cercus; cerp: acute ventral projection of the cercus; epi: epiproct; hypo: hypoproct; pg: postgonite; ph: phallus; sur: surstylus; s6, 7 & 8: sterna 6, 7 & 8; t7 & 8: terga 7 & 8.

FIGURE 41. Distribution map for Orthonevra flukei (sedman, 1964), O. gli sp. nov., O. hypnotica sp. nov., O. nitidula (Curran, 1925), and O. sternolobosa sp. nov.