Empis (Pachymeria) vikhrevi, 2019

Shamshev, Igor V. & Barták, Miroslav, 2019, New and little-known species of Empis (Diptera: Empididae) from Bulgaria, Israel and Turkey, with keys to the Palaearctic Pachymeria and the Mediterranean Xanthempis, Zootaxa 4555 (1), pp. 91-100 : 92-95

Empis (Pachymeria) vikhrevi sp. nov.

( Figs 1–4 , 7 )

urn:lsid:zoobank.org:act:569581CD-3A05-4A1C-8308-897C35330441

Type material. HOLOTYPE , ♂ labelled: “ Turkey, Bolu pr., Kartalkaya / env. (40.642N 31.763E) 1480m / 16– 18.vi.2010, N. Vikhrev ”; “ Empis (Pachymeria) / vikhrevi Shamshev et Barták , sp. n. [red label]” (ZMUM). PARATYPES: TURKEY: same data as holotype (1 ♀ ZMUM, 1 ♂ and 1 ♀ ZIN) . BULGARIA: Pirin Mountains , 6 km SE of Bansko, 1300–1600 m, 41°47´N 23°29´E, forest, 1.vii.2016, Barták, Kubík (1 ♂, 4 ♀, CULSP) .

Diagnosis. Light grey pollinose species with dichoptic eyes in both sexes, antennal postpedicel largely reddish yellow; palpus yellow; thorax with black setation only, scutum densely brownish grey pollinose with faint black vittae beneath rows of acrostichal and dorsocentral setae; legs yellow to brownish yellow (except blackish coxae). Male: hind femur only slightly thickened, hind tibia slender throughout; abdomen densely light grey pollinose. Female: hind femur distinctly thickened, hind tibia thickened on basal part; abdominal tergites densely silvery white pollinose.

Description. Male ( Fig. 1 ). Body length 4.3–5.6 mm; wing length 6.1–6.9 mm. Head black. Eyes dichoptic, ommatidia of equal size. Frons narrow above, broadened below, in narrowest part about twice as broad as anterior ocellus; with scattered minute marginal setulae, entirely densely light grey pollinose. Face wide, almost parallelsided, concolourous with frons, bare; clypeus subshiny. Occiput and ocellar tubercle concolourous with frons; occiput covered with numerous, moderately long, black thin setae; ocellar tubercle with 2 similar setae and several setulae. Antenna with scape rather brownish, pedicel reddish brown (paler on extreme apex), postpedicel largely reddish yellow (brownish on narrowed apical part), stylus dark brown; scape about 2 x longer than pedicel, both with short black setulae; postpedicel short, nearly 2 x longer than wide, deeply concave on subapical part ventrally; stylus about half as long as postpedicel. Proboscis long, labrum nearly 2 x as long as head height; palpus short, yellow, with scattered black setulae.

Thorax black, densely light grey pollinose (except noted); with black setation only; scutum densely brownish grey pollinose; in dorsal view with faint black vittae beneath rows of acrostichal and dorsocentral setae (rather brownish in anterior view). Prosternum with scattered short black setae separated by broad bare space from lower proepisternal setae. Proepisternum with 3–5 similar setae on lower and upper parts. Antepronotum with 8–9 setae of different lengths on each side. Postpronotal lobe with 1 long and numerous short setae. Mesonotal setation: 2 presutural supra-alars (posterior longer), 4–5 notopleurals (3 posterior longer), 2 postsutural supra-alars (posterior much longer), 1 very long postalar, 4 subequally long scutellars, some additional setulae present on supra-alar face and on notopleuron; acrostichals arranged in 2 close rows, short, lateroclinate, lacking on prescutellar depression; dorsocentrals arranged in 2 irregular rows, short and lateroclinate before suture, uniserial and long in front of scutellum, flanked with 1 long seta (intra-alar) and several setulae anteriorly. Laterotergite with numerous setae. Anterior and posterior spiracles pale yellow.

Leg colour: coxae concolourous with mesopleuron; fore and mid trochanters brownish yellow, hind trochanter brownish; fore femur broadly brownish yellow leaving extreme base and subapical part yellow, fore and mid tibiae narrowly brownish yellow on apex, fore basitarsus brownish on apex, tarsomeres 2–4 of all legs extensively brownish (except extreme basal part), tarsomere 5 entirely brown, otherwise legs yellow. Coxae and trochanters with rather sparse black setae. Fore femur with short thin anteroventral and posteroventral setae, similar somewhat longer setae anteriorly and posteriorly on subapical part. Fore tibia with somewhat longer posteroventral setulae throughout, without prominent strong setae (except circlet of moderately long subapicals). Fore basitarsus slender, with 2–3 spine-like anteroventral setae of different lengths near base (besides circlet of subapicals), otherwise covered with simple setulae, tarsomere 5 nearly as long as tarsomeres 3–4 combined. Mid femur with rows of numerous short thin anteroventral and longer, stronger posteroventral setae. Mid tibia with 5 moderately long anterodorsal, 4 similar posterodorsal and 4–5 posteroventral setae (besides circlet of subapical setae). Mid basitarsus with 2 short anteroventral setae on apical part (besides circlet of subapicals), tarsomere 5 nearly as long as tarsomeres 3–4 combined. Hind femur at middle only slightly broader than fore femur; covered with dense short black setulae ventrally, bearing 5 moderately long anterodorsal setae on apical part, bare anteriorly. Hind tibia slender, nearly as broad as mid tibia, pubescent with dense dark erect minute setulae ventrally, with 5–6 short dorsal setae (besides circlet of subapicals); no seta in “comb” at tip behind. Hind basitarsus slender, with some short spine-like setae ventrally; tarsomere 5 nearly 1.5 x shorter than tarsomeres 3–4 combined. Claws of fore and mid legs very long and longer than claw of hind leg; claws of all legs largely reddish, blackish apically.

Wing membrane hyaline; veins brown (except yellowish brown near extreme base of wing). Pterostigma faint, yellowish, narrow. Basal costal seta long, black. Veins R 5 and M 1 strongly divergent on subapical part; radial fork acute. Anal angle very acute, subsequently anal lobe well developed. Calypter pale yellow, pale fringed. Halter yellow.

Abdomen black, densely light grey pollinose, with only black setation; tergites covered with rather sparse thin setae, longer on tergites 1–2 laterally, bearing long posteromarginal setae. Terminalia ( Figs 3, 4 ) small; epandrial lamella and cercus contrastingly dark brown; epandrial lamella rather rhomboid, with lower posterior angle more acute and somewhat produced downwards; faintly tomentose, with black setation, longer setae on lower part; cercus small, clothed in dark setulae; phallus partly exposed, brownish yellow, thin, evenly curved; hypandrium non-visible in situ, reduced to two lateral arms.

Female ( Fig. 2 ). Body length 5.8–6.7 mm; wing length 6.3–6.6 mm. Similar to male except as follows: Frons broad, parallel-sided. Occipital setae somewhat sparser and stronger. All femora brownish dorsally on basal part; fore tibia with rows of short anterodorsal and posterodorsal setae, also bearing row of several short posteroventral setae, fore basitarsus with several spine-like setae ventrally, fore tarsomere 5 shorter than tarsomeres 3 and 4 combined; mid femur with sparse anteroventral and posteroventral setae, setae minute on subapical part and longer towards base; mid tibia with more numerous and stronger setae arranged in almost regular double dorsal and ventral rows; mid basitarsus with several spine-like setae ventrally; mid tarsomere 5 shorter than tarsomeres 3 and 4 combined; hind femur thickened on about middle, bare ventrally, only with row of short, sparse spine-like anteroventral setae on about apical 2/3; hind tibia thickened on basal part, with ventral pubescence only on middle part, bearing 3–4 very short anterodorsal setae (1–2 near apex and 2 near base), 4–5 longer posterodorsal setae spread more or less regularly, 2–3 short anteroventral setae near apex and 3–4 very short anteroventral setae near base (number variable, sometimes even on right and left legs); hind basitarsus with several spine-like setae ventrally; claws of all legs of equal lengths. Abdominal tergites 2–6 densely silvery white pollinose, tergite 1 entirely, tergite 7 posteriorly, sternites 1–6 entirely and sternite 7 posteriorly densely light grey pollinose; segment 8 contrastingly dark brown, shiny, except tergite 8 faintly greyish pollinose posteriorly. Abdominal tergite 1 with some moderately long setae, otherwise abdomen covered with scattered minute black setulae; cercus concolourous with segment 8, short, covered with black setulae.

Etymology. The new species is named in honour of the collector of the holotype, Russian dipterist Nikita Vikhrev (Moscow), who kindly provided his very interesting specimens used in this study.

Differential diagnosis. Empis vikhrevi sp. nov. is similar to E. tumida Meigen and its allies (Shamshev 2018). The new species differs from all species of Pachymeria by extensively reddish yellow postpedicel of the antenna in both sexes. Like some other species of Pachymeria , females of E. vikhrevi sp. nov. can be even more readily distinguished by an unique combination (besides reddish yellow postpedicel) of the hind femur thickened near mid-length, the hind tibia thickened on basal part, and the densely silvery white pollinosity on abdominal tergites 2–6.

The new species could be E. ruficornis (Loew) , which is an unrecognised species of either Pachymeria , or Polyblepharis Bezzi possessing red antennae (see discussion in Chvála 1999: 197). Loew described this species in Pachymeria from south-eastern Europe (“ Bessarabia ”). However, he ( Loew 1864: 366) notes that in E. ruficornis the abdomen is rather shiny black, the laterotergite bears black and pale yellow setae, the wing veins are yellowish and the body is about 11 mm.

Distribution. Palaearctic: Bulgaria, Turkey ( Fig. 7 ).

Habitat and seasonal occurrence. According to the label data, the new species occurs in mountainous areas (1300–1480 m), like several other species of Pachymeria ; dates of collecting refer to the second half of June.

Remarks. Two species of Pachymeria are known now from Bulgaria ( Kanavalová et al. 2018) and five species from Turkey ( Çiftçi & Hasbenli 2007a, 2013).

Figures

FIGURE 7. Distribution of Empis (Pachymeria) vikhrevi sp. nov., Empis (Xanthempis) adanaensis sp. nov. and E. (X.) testiculata Bezzi in the Palaearctic Region.

FIGURES 1–4. Empis (Pachymeria) vikhrevi sp. nov. 1. male habitus, holotype, lateral view; 2. female habitus, lateral view; 3. cleared preparation of male genitalia, lateral view; 4. outline of male terminalia (setation omitted), lateral view. Abbreviations: cerc—cercus; ej apod—ejaculatory apodeme; epand—epandrium; hypd—hypandrium; ph—phallus.