Aspistomella steyskali Kovac & Kameneva & Korneyev & Araújo & Savaris & Smit & Schneider & Schreiber & Korneyev 2024, sp. nov.
Creators: name: Kovac, Damir
name: Kameneva, Elena P.
name: Korneyev, Severyn V.
name: Araújo, Alexandre Santos
name: Savaris, Marcoandre
name: Smit, John T.
name: Schneider, Alexander
name: Schreiber, Robert
name: Korneyev, Valery A.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Ulidiidae
Aspistomella
Aspistomella steyskali

description: Aspistomella steyskali Kameneva & S. Korneyev, sp. nov.
urn:lsid:zoobank.org:act: DF48CB4F-3710-4FC5-97E7-13DD96619F2A
Figs 5 F, 40–41
Material examined. Type. Holotype ♂: “ Ecuador: Napo Province / Huahua Sumaco, km 45, on Hollin-Loreto rd / Mal.[aise] trap, XII-14-[19]89 / M. J. Wasbauer, H. Real ” [leg.] (CSCA). Paratypes: Ecuador: Napo Province, Huahua Sumaco, km 45, on Hollin-Loreto rd Mal.[aise] trap, 13.12.1989, 1♀, 14.12.1989, 8♀, 15.12.1989, 1♂ [dissected], 7♀, 16.12.1989, 3♀, 17.12.1989, 1♂, 10♀, 18.12.1989, 2♂, 7♀, 20.12.1989, 6♂, 12♀, 21.12.1989, 1♂, 3♀, 22.12.1989, 3♀ [1♀ dissected] (M. & J. Wasbauer, H. Real leg.) (CSCA, SIZK, MNKB); Past Province, Puyo, 18.05.1977, 1♀; Napo Province, Tena, 24.05.1977, 2 ♀ (D. & S.S Vincent) (USNM). Bolivia: Province La Paz, Mapiri, Arroyo Tuhuri, 508 m, -15.290556 (S), -68.262778 (W), 10.IV.2004, 1♀ (S.D. Gaimari) (CSCA). Brazil: Mato Grosso, base camp, 12º50'S, 51º45'W, gallery forest, 10– 27.03.1968, 1♂, 1♀ (dissected) (B.E.Freeman) (BMNH).
Diagnosis. Aspistomella steyskali is similar to A. enderleini, A. lobioptera, and A. lunata in having wing wide oval with similar pattern (hyaline base, widely dark wing disc and apex with long crescent-shaped incision extending from cell r 1 into cell m 1; cell r 1 with cuneiform hyaline incision distally or apex of vein R 1. It differs from A. lunata by the first incision extending posteriorly only into cell r 2+3 (A. lunata, into base of cell r 4+5), from A. lobioptera by hyaline subapical mark in cell dm (in A. lobioptera, cell dm entirely dark) and non-modified, moderately developed phallus (in A. lobioptera, phallus is extremely long and densely trichose). Aspistomella steyskali is most similar to A. enderleini in the wing shape and pattern: apex with long crescent incision extending into cell r 1, differing from it by the slightly shorter pterostigma and structure of male genitalia: outer surstylus with elongate anteroventral lobe and wide rounded posterior lobe, inner surstylus with 3–4 thick prensisetae (in A. enderleini, surstyli ventrally blunt, with posterior margin short dentate, without expressed lobes and with slightly thickened setae, but no prensisetae).
Description. Male. Head (Figs 40 A, B) ratio (length: height: width) = 1: 1.6: 1.9, colouration as described for A. lobioptera. Frons slightly narrowed posteriorly, 1.4–1.5× longer than wide at lunule and 1.5–1.6× longer than wide at vertex; orbits, vertex, gena and occiput silver-white microtrichose; parafacial narrow, 0.2–0.4× broader than postpedicel, reddish-yellow, sparsely white microtrichose. Frontal plates at each side with 4–6 parafrontal setulae and 2–3 inclinate frontal setae as long as outer vertical seta, frontal vitta whitish microtrichose, with 2–8 shorter, proclinate or inclinate interfrontal setae (Fig. 40 A). Lunule very narrow. Eye 1.36–1.46× higher than long. Face as in A. lobioptera. Gena with long genal seta and 4–5 additional long peristomal setae anterior of it, 0.5–0.8× longer than genal seta. Occiput with cyan metallic sheen, greyish microtrichose. Antenna: postpedicel twice as long as wide, apically rounded; arista almost bare. Palp narrowly crescent-shaped, apically rounded, as in A. lobioptera.
Thorax (Figs 40 B, C) colouration as described for A. lobioptera, with bluish sheen and sparse white and brown microtrichia not hiding underlying cuticle. Mesonotal scutum 1.25–1.3× longer than wide; black setulose, with 10– 14 rows of setulae between rows of dorsocentral setulae; acrostichal prescutellar seta present, strong; prescutellar area with 4 rows of setulae between posterior dorsocentral setae. Scutellum dorsally slightly convex, subshining, sparsely microtrichose, without setulae, with silver or bluish sheen. Subscutellum shining. Mediotergite shining, non-microtrichose medially.
Wing (Figs 5 F, 40 F) 2.95–3.36 mm long, 2.6–2.9× longer than wide; basicostal cell hyaline; costal cell lobate, 4× longer than wide, brown in basal and apical quarters of length, with costa conspicuously curved, posteriorly covered with longer setulae and forming conspicuous cleft before apex of vein Sc; pterostigma entirely brown, narrow triangular, 0.3–0.6× longer than wide and 0.25–0.5× longer than costal cell width, vein R 1 bare, ending far proximally of crossvein r-m level in both sexes; vein R 2+3 sinuate, at apex bent anteriorly to costa. Crossvein r-m distally of middle of cell dm. Cell r 4+5 5.5–7× longer than wide, apically narrowed. Cell m 1 subtriangular; ultimate section of M 1 2.5–3.5× longer than crossvein dm-m and 1.3–1.7× longer than penultimate section. Vein CuA Zshaped, forming moderately short posteroapical lobe of cell cua along vein CuP, 1.1–1.2× longer than its anterior shoulder. Wing pattern with short subbasal crossband from humeral vein through cell cua into alula, and large dark brown mark from apical lobe of costal cell to wing apex, with 4 hyaline marks: incision from cell r 1 through cell into cell r 2+3 basally of crossvein r-m, two oval spots in base of cell r 4+5 and in apex of cell m 4 and long and narrow crescent or arcuate incision from apex of cell m 1 into cell r 1 parallel to wing apex (Fig. 5 F). Cell cup (anal cell sensu Kameneva & Korneyev 2010) and anal lobe as wide as cell cua. Alula, calypters and halter as in A. lobioptera.
Legs as in A. lobioptera.
Abdomen brown to black, sparsely black setulose.
Male genitalia (Figs 41 A–F) with short, non-projecting cerci, trilobate surstyli having short, bidentate antero-ventral, narrow elongate meso-ventral and thin, wide, rounded posterior lobes and one to three thick dentate prensiseta on mesal surface. Phallus moderately long and thick, at most 3 times as long as epandrium high, sparsely trichose. Hypandrium with phallic guide forming pair of partly sclerotised, blade-like posteriorly directed projections exceeding level of surstyli, pair of postgonites with 5 trichoid sensilla on lateral surface of phallic guide and pregonites with 3–5 trichoid sensillae at antero-medial side (Figs 41 D, E).
Female terminalia: aculeus with ovoid, long-setulose cercal unit (Fig. 41 H); 2 globose spermathecae (Fig. 41 I).
Etymology. Named in honour of George Constance Steyskal (1909–1996), the American dipterist, who first recognised it as a separate species in his manuscript keys.
description: Published as part of Kovac, Damir, Kameneva, Elena P., Korneyev, Severyn V., Araújo, Alexandre Santos, Savaris, Marcoandre, Smit, John T., Schneider, Alexander, Schreiber, Robert & Korneyev, Valery A., 2024, Revision of the Aspistomella group of genera (Diptera: Ulidiidae: Pterocallinae: Lipsanini), pp. 1-117 in Zootaxa 5530 (1) on pages 68-69, DOI: 10.11646/zootaxa.5530.1.1, http://zenodo.org/record/14023149