Hilara bulgarica Bartak

Kanavalova, Liliana, Kubik, Stepan & Bartak, Miroslav, 2018, Empidinae (Diptera, Empididae) from Bulgaria with new records and descriptions of three new species, ZooKeys 785, pp. 145-161 : 145

Hilara bulgarica Bartak sp. n. Figs 3, 4

Type material.

HOLOTYPE ♂, Bulgaria, Rhodopes Mountains, Pamporovo env., meadow, 41.65N, 24.73E, 1600 m, Barták & Kubík, 22.-24.vi.2016 (CULSP). PARATYPES: 16♂, 2♀, same data as holotype; 6♂, 1♀, Rhodopes Mountains, Yundola, 1300 m, pasture 42.063N, 23.855E, Barták & Kubík, 30.vi.2016; 2♂, Rhodopes Mountains, Sniezhanka peak, 1900m, hilltop, 41.637N, 24.680E, Barták & Kubík, 24.-25.vi.2016; 1♂, Rhodopes Mountains, 25km SSW of Plovdiv, 1590 m, meadow, 41.935N, 24.679E, Barták & Kubík, 20.vi.2016; 4♂, 1♀, 9km NEE of Dospat, meadow nr. wood, 1170 m, 41.670N, 24.264E, Barták & Kubík, 23.vi.2016; 2♂, 1♀, Pirin Mountains, 6km SE of Bansko, 1300-1600 m, 41.78N, 23.48E, forest, Barták & Kubík, 1.vii.2016; 3♂, Pirin Mountains, Vikhren hut, 2000 m, alpine meadow, 41.756N, 23.415E, Barták & Kubík, 27.vi.2016 - (CULSP).

Diagnosis.

Middle sized species of the Hilara intermedia group with mesoscutum light grey with four dark brown stripes visible in anterodorsal view, changing into one broad dark stripe in posterodorsal view, reaching anterior margin of prescutellar depression (in some specimens median stripe down acrostichals lighter even in posterior view, more conspicuously in females); occiput uniformly dull black and male fore basitarsus extremely enlarged.

Etymology.

The species is named after country of its origin (Bulgaria).

Description.

Male head black, occiput dull black from dorsal view and brownish grey in posterior view with slight indication of somewhat lighter narrowly V-shaped spot behind ocelli; frons wide (0.1 mm broad at narrowest point - approx. twice as broad as anterior ocellus) dull black in dorsal view; rather light grey with dull black margins in anterior view; face light grey and broader than frons, black lateral margins narrower and less conspicuous than those on frons. Eyes with all facets of equal size. Both ocellar and one pair of frontal setae long (0.3 mm - slightly longer than postpedicel), frons with 3-7 pairs of much shorter hairs ventrally and 0-1 pairs of similar hairs dorsally of frontal pair. Postocular row of setae complete, setae black, rather fine and long, with shorter setae behind them, lower part of occiput with rather fine and somewhat longer setae, only several of them just below neck paler. Clypeus and narrow gena entirely almost silvery microtrichose. Palpus black, almost silvery grey microtrichose, usually with 1-2 long and strong ventral setae (longest seta up to 0.47 mm long, approx. as long as labrum) and with many additional fine rather long setae ventrally. Labrum brownish black, polished, 2/3 as long as head height; postmentum nearly as broad and long as labellae with apical circlet of black hairs similar to those on labellae. Antenna black, both basal segments short setose; length of antennal segments (scape: pedicel: postpedicel: 1st segment of stylus: stylus: bare part of stylus) = 0.06-0.08 mm: 0.06-0.08 mm: 0.2-0.25 mm: 0.02-0.03 mm: 0.13-0.18 mm: 0.03-0.04 mm.

Thorax black, grey microtrichose, mesoscutum with four dark brown stripes in anterodorsal view (inner pair of stripes between rows of acrostichal and dorsocentral setae narrow, running from antepronotum to posterior acrostichals, outer pair outside dorsocentrals broader), spaces occupied by rows of setae rather brownish grey; in posterodorsal view this pattern changes and mesoscutum except posterior part appears dark almost velvety black (in some specimens median stripe down acrostichals somewhat lighter even in posterior view); prescutellars depression and scutellum very light, and from almost all points of view almost silvery microtrichose; pleuron light (almost bluish) grey. Chaetotaxy: proepisternum with fine pale setulae; prosternum without setae; acrostichals black, irregularly biserial (with tendency to be triserial on middle or posteriorly) and short (approx. 0.09 mm); dorsocentrals uniserial, slightly longer than acrostichals, ending in two pairs of long prescutellars; postpronotal and posthumeral (presutural supraalar) setae long and strong, intrahumeral (presutural intraalar) fine and very short; antepronotum with two strong black setae on sides and 3-5 additional fine but rather long additional setae between them; notopleuron with 2-3 setae (and 6-8 fine yellowish brown setulae on anterior part); one supraalar and one postalar strong setae, prealar region with several setae similar to those on front part of notopleuron; two pairs of scutellars, outer pair shorter. Legs: coxae concolorous with pleura, with both yellow and brown setae (smaller setae usually pale, larger darker); more distal parts of legs brownish-black with nearly all setae black, tarsi almost black, microtrichose, knees narrowly yellowish. Fore femur (Figure 3) short setulose, posteroventrally almost bare except several preapicals. Fore tibia apically slightly swollen (at tip subequally deep as femur in middle), dorsally with 2-5 long setae, preapical circlet consists of 4-5 long setae, basitarsus extremely swollen and long, as long as or longer than tibia, rather flattened ventrally, short setulose, tarsomeres 2-4 short, approx. as long as deep. Mid femur short setose, subbasal ventral hair fine and short, anterior setae poorly differentiated. Mid tibia with 1-3 short anteroventral setae and with slightly elongated fine anterodorsal setae slightly longer than tibia depth. Hind femur with dorsal and ventral setae fine and shorter than tibia depth. Hind tibia thin, short setose, 1-3 anteroventral setae shorter than tibia depth, dorsal setae longer than tibia depth, preapical the longest; mid and hind basitarsi ventrally with short spines. Wings clear, veins brownish-black, stigma brown, anal vein long, radial fork long, axillary angle obtuse (approx. 130°) costal seta short (approx. as long as outer scutellar). Halter clear yellow, calypter grey with brownish margin and long yellow fringes.

Abdomen rather long and narrow, brownish-black, very light grey microtrichose, appearing lighter and more brownish than thorax. Lateral marginal setae on tergites 2-6 approx. as long as segments, those on segment 1 and partly (on sides) of segment 2 white to light brownish, on remaining segments black; discal setae very short and black (except somewhat longer whitish setae on segment 2), segment 7 very short setose and marginal setae on segment 8 short (longest setae up to 0.15 mm long, ventral marginal setae not distinctly longer than discal ones); sternites with very short white (on basal segments) to light brownish setae. Genitalia as in Fig. 4: hypandrium almost equally strong nearly to apex; epandrial lamella with narrow and C-shaped apical outgrowth.

Length. body 4.1-6.1 mm, wing 4.0-4.7 mm.

Female. Very similar to male in all characters except legs. Fore tibia with 2-4 setae dorsally slightly longer than tibia depth. Mid tibia with only 1-2 setae ventrally shorter than tibia depth. Hind tibia practically unmodified, only very indistinctly curved in dorsal view, setae similar as in male but shorter. All tarsi slender and rather long, short setose. Abdomen with shorter marginal setae than in male. Length. body 4.0-4.8 mm, wing 3.6-4.1 mm.

Remarks.

Hilara bulgarica sp. n. is a member of the H. intermedia group similar to H. polleti Chvála, also described from Bulgaria. Both species clearly differ by the shape of apical process of epandrial lamella, which is rounded and spinose in the latter species. Shape of this process in the newly described species (and four dark thoracic stripes broadly coalescent in posterior view) resembles that of H. beckeri Strobl. The latter species differs in many characters, for example, it has quadriserial acrostichals and strongly curved hind tibia in the female. Moreover, the species described above cannot be confused with any other member of the H. intermedia group due to extremely enlarged male fore basitarsus.