Aspistomella pachitea Kameneva & V. Korneyev, 2024

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), Zootaxa 5530 (1), pp. 1-117 : 58-61

Aspistomella pachitea Kameneva & V. Korneyev , sp. nov.

urn:lsid:zoobank.org:act:87F9EAAA-F2E1-4AFE-ADC0-01AA95ADD57A

Figs 5 A , 34–35

Material examined. Type. Holotype ♀: “ Peru — 150 m / 26.11.[19]03 / Pachitea-Münd [8.76S, 74.53W] ” [Schnuse leg.] ( SMTD) (left wing and apical half or right wing missing) . Paratype: 1♂: “ Peru — 150 m / 19.11.[19]03 / Pachitea-Münd” [Schnuse leg.] [head missing; abdomen dissected and attached in microvial] ( SMTD) .

Diagnosis. Aspistomella pachitea is similar to other species of the genus in that the epistome is high, the costal vein forms a conspicuous cleft before the apex of the subcostal vein, and the pterostigma is very short, shorter than the width of the costal cell ( Figs 34 C–D , 5 A ), but differs from them in that the costal vein is straight, costal cell is not lobed, the vein r-m distally from the R 1 apex, and in the details of the wing pattern: wing disk gradually darkening from pale grey at anterior margin to brown at posterior margin, without any hyaline incisions, spots or bands (in other species of the genus, the costal vein is conspicuously arcuate proximally to the apex of the subcostal vein, and the wing pattern is predominantly brownish-yellow to dark brown, with hyaline triangular incisions and rounded spots). It is most similar to A. duo , A. heteroptera and A. tres in having very short pterostigma, brown halter, no acrostichal setae, male genitalia with the outer surstyli with narrow mesally directed ventral process ending by a tiny pimple-like process and moderately large projected cerci, differing by the narrowest frons in the group, straight, non-lobed costal cell, bare vein R 1 and different type of with pattern and venation. It also differs from the other species of Aspistomella by the distinctly curved apical section of vein M 1 sharing this character only with A. heteroptera and several species here assigned to Ulivellia and other genera of this group.

Description. Male. Head ( Figs 34 C–E ) ratio (length: height: width) = 1: 1.43: 1.62, frons, parafacial, and gena yellow to yellowish brown, face and occiput mostly dark brown to black. Frons slightly narrowed posteriorly ( Figs 34 D, E ), 1.06× longer than wide at lunule and 1.46× longer than wide at vertex, with subshining, brown ocellar triangle and brownish yellow vertical plates; orbits, vertex, gena and occiput silver-white microtrichose; parafacial narrow, 0.2× broader than postpedicel, yellow, sparsely white microtrichose. Frontal plates with 5 pairs of inclinate frontal and interfrontal setae as long as outer vertical seta, and one submarginal row of 5 very short parafrontal setulae; frontal vitta sparsely whitish microtrichose, with 3 shorter, frontal setulae above lunule ( Fig. 34 D ). Lunule indistinguishable. Eye 1.55× higher than long. Face strongly produced anteriorly, brown, densely white microtrichose (above epistome); epistome brown, sparsely white microtrichose, with metallic bluish sheen. Clypeus low, yellowish brown, sparsely white microtrichose. Gena brownish yellow, with long genal seta and 6–7 additional long peristomal setae anterior of it, 0.4–0.6× longer than genal seta. Occiput black, white to greyish microtrichose.

Antenna yellow; scape and pedicel with black setulae; postpedicel yellow, whitish microtrichose, twice as long as wide, apically rounded; arista black except basal 0.15 yellow, almost bare. Mouthparts black, prementum black, shining. Palp yellow, as in A. lobioptera .

Thorax ( Figs 34 A–C ) black, with bluish sheen and sparse white and brown microtrichia not hiding underlying cuticle. Mesonotal scutum 1.25× longer than wide; black setulose, with 5–6 rows of setulae between rows of dorsocentral setulae; acrostichal prescutellar seta absent; prescutellar area without setulae between posterior dorsocentral setae. Other setae as described for the genus. All the setae and setulae black. Scutellum dorsally flattened, yellowish brown to brown, subshining, sparsely microtrichose, devoid of setulae, with bluish sheen. Subscutellum subshining, black. Mediotergite shining black, non-microtrichose medially.

Wing ( Fig. 5 A ) 4.3 mm (♂) long, 2.55× longer than wide; basicostal cell hyaline; costal cell straight, 5× longer than wide, pale grey, brownish in basal 0.16 of length, with costa straight, almost uniformly setulose, slightly thickened and forming cleft before apex of vein Sc; pterostigma entirely brown, linear, vein R 1 bare, ending proximally of crossvein r-m level in both sexes; vein R 2+3 straight. Crossvein r-m basally of middle of cell dm. Cell r 4+5 5× longer than wide, apically narrowed. Cell m 1 subtriangular; ultimate section of M 1 conspicuously upcurved, 2.35× longer than crossvein dm-m and 1.1× longer than penultimate section. Vein CuA Z-shaped, forming moderately short posteroapical lobe of cell cua along vein CuP, as long as its anterior shoulder. Wing uniformly grey microtrichose, subhyaline at anterior margin and apex and brown in posterior half. Cell cup (anal cell sensu Kameneva & Korneyev 2010) and anal lobe brown as wide as cell cua. Alula 2.6× longer than wide, uniformly dark grey. Calypters brownish, with pale brown ciliae. Halter brownish yellow, with brown knob.

Legs ( Figs 34 A–B ): coxae and trochanters, apices of femora yellow, fore femur anteriorly brownish-yellow, otherwise black; tibiae and tarsi yellow; black setose and setulose. Fore femur with 2 rows of 4–6 posterodorsal, but without strong posteroventral setae. Mid femur anteriorly with short suberect setulae; mid tibia ventrally with single spur-like seta 3× longer than tibia width.

Abdomen brown to black, sparsely black setulose.

Male genitalia ( Figs 35 B–G ) with short, but projected, separate cerci, moderately narrowed; surstyli simple with narrow, mesally directed ventral lobe apically bearing dorsally directed pimple-like process, but without distinct antero-ventral and postero-ventral lobes; one row of 4–5 short setulae on mesal surface of inner surstylus ( Figs 35 C, F ). Phallus moderately short, 2× longer than epandrium height, bare ( Fig. 35 D ). Hypandrium: phallic guide with suboval lobes forming no conspicuous posterior projections, bearing pair of oval postgonites anterior to basiphallus ring, and symmetrical pregonites anterolateral to them, both with groups of 5–6 trichoid sensillae ( Fig. 35 G ).

Female terminalia: not examined.

Etymology. The name of the species is a noun in apposition derived from its type locality, the Pachitea River, a tributary of the Ucayali.

Figures

FIGURE 5. Aspistomella, wing. A, A. pachitea sp. nov.; B, A. heteroptera Hendel; C, A. duo sp. nov.; D, A. tres sp. nov.; E, A. lobioptera Hendel; F, A. steyskali sp. nov.; G, A. lunata (Hendel); H, A. enderleini sp. nov. Abbreviations: C—costal vein; c—costal cell; dm—discal medial cell; h—humeral crossvein; M1—first branch of media; M4—fourth branch of media; m1— first medial cell; m4—fourth medial cell; ptstg—pterostigma; R1—anterior branch of radius; r1—first radial cell; R2+3—second branch of radius; R 4+5 —third branch of radius; r 4+5 —fourth + fifth radial cell. Scale bar: 1 mm.

FIGURE 34. Aspistomella pachitea sp. nov., holotype ♀ (B–E, G) and paratype ♂ (A, F) (SDEI). A, B, habitus, left; C, head and thorax left; D, head, anterior; E, head and thorax, dorsal; F, G, labels.

FIGURE 35. Aspistomella pachitea sp. nov., paratype ♂ genitalia (SDEI). A, abdomen, ventral; B, postabdomen and apical part of preabdomen; C, postabdomen, posterior; D, same, lateral; E, ejaculatory apodeme; F, postabdomen, ventral; G, hypandrium, ventral.