Platypalpus vercorsensis, Barták & Grootaert, 2024

Barták, Miroslav & Grootaert, Patrick, 2024, Description of twelve new species of Platypalpus Macquart from Europe and the Middle East (Diptera, Empidoidea, Hybotidae), Zootaxa 5443 (2), pp. 161-185 : 165-167

Platypalpus vercorsensis sp. nov.

( Figs 3 , 4 )

Type material. HOLOTYPE ♂: FRANCE, Col de Tourniol , 1050 m, pasture + wood, SW [= sweeping vegetation], 44°55′06″N, 5°11′04″E, 26.v.2006, M. Barták ( CULSP) . PARATYPES: FRANCE, same data as holotype (6 ♂, 3 ♀)—( CULSP) .

Diagnosis. Small black species of the P. longicornis group. Two pairs of vertical setae. Antennae with basal segments yellow, postpedicel yellow with darkened tip in male and brown in female. Proboscis yellow. Mesoscutum light grey microtrichose, in male with only small lustrous spot on posterior third but with larger lustrous spot in female. Legs pale yellow including tarsi, mid femur narrow, spur on mid tibia very short.

Description. Male ( Fig. 3 ). Head black, light grey microtrichose, frons brown in dorsal view and almost silvery in ventral view, face with slight yellowish tinge, clypeus microtrichose. Frons ≈ 0.05 mm broad at ventral part (about as wide as pedicel) and 0.09 mm broad at level of anterior ocellus. Face ≈ 0.03 mm broad at middle. Gena very narrow, indistinct.Antenna yellow, postpedicel darkened on apical third or less, stylus brown; postpedicel 2.5× longer than broad, stylus shorter, 0.6–0.7× postpedicel. Clypeus microtrichose. Palpus broadly oval, yellow, with short silvery hairs. Ocellar setae pale yellow, ≈ 0.15 mm long (ocellar triangle with 3 pairs of additional short setae behind anterior pair of ocellars). Two pairs of yellow vertical setae, inner pair about as long as ocellars, rather widely separated (≈ 0.18 mm apart), outer pair strongly lateroclinate and shorter. Occiput with pale setae longer ventrally. Proboscis yellow, half as long as height of head. Thorax black, mesoscutum thinly light grey microtrichose, with lustrous patch of various extent, in most specimens occupying area between last two pairs of dorsocentrals, in one specimen almost absent; katepisternum with lustrous spot leaving narrow anterior and broader posterior part microtrichose. All setae pale yellow. Chaetotaxy: 1 long postpronotal seta; acrostichals narrowly biserial, rather long (≈ 0.06 mm), more than 10 setae in one row; dorsocentrals irregularly 2–3 serial (with several setae outside rows), last 1–2 pairs longer; notopleuron with 2 setae on posterior part and several short hairs; 1 postalar and 1 pair of scutellar setae (with 2 smaller hairs). Wing clear, veins yellow. R 4+5 and M 1 almost parallel apically. R 1 thickened apically. Crossveins contiguous or narrowly separated. CuA recurrent and slightly S-shaped. Costal seta yellow, short. Squama yellow with yellow fringes. Halter pale yellow. Legs yellow including coxae and tarsi (except usual dark spot on all trochanters). Setae pale (except some ventral spines on mid femur and tibia). Fore femur moderately thickened on basal third, with antero- and posteroventral rows of setae one third as long as femur depth. Fore tibia narrow. Mid femur not deeper than fore femur, without posteroventral setae; ventral spines partly yellow and elongate especially in posteroventral row. Mid tibia with very short inconspicuous pale apical spur. Hind femur and tibia narrow (femur slightly broader than tibia), short setose. Abdomen blackish-brown, lustrous, tergite 1 and narrow base of tergite 2 microtrichose; sparsely covered with short pale setae, somewhat longer setae on sides of tergites and on sternite 8. Terminalia ( Fig. 4 ): cerci nearly equally long ( Fig. 4B ). Right cercus with broad apex, pointed at left side. Left cercus more digitiform with weakly pointed tip. Right epandrial lamella with about 7 rather long, interspaced setae at middle of right border. Setae at base of right surstylus unusually short and fine, much shorter than length of surstylus ( Fig. 4A ). Left epandrial lamella with broadly rounded apex, set with short setae, only a few quite short setae on left margin ( Fig. 4C ). Female. Similar to male except as follows: postpedicel brown including base, mesoscutum with much larger lustrous spot occupying whole central part of mesoscutum with exception of anterior part and narrow margins, last two abdominal segments microtrichose. Length. Both sexes: body 1.9–2.1 mm, wing 2.1–2.5 mm.

Etymology. The species name is derived from the name of the mountain range Vercors ( France), where this species was found.

Distribution. France.

Remarks. The species described above may be easily identified according to the yellow proboscis (very rare among West Palaearctic Platypalpus , e.g., known in P. novakii (Strobl)) , short stylus and conspicuous sexual dimorphism of antennae and extent of lustrous spot on mesoscutum.

In the key to European species ( Grootaert & Chvála 1992), P. vercorsensis sp. nov. will lead to couplet 183 in having two pairs of vertical setae, pleura dusted except for the polished anepisternum. In having biserial acrostichals and postpedicel 2.5× longer than deep, it will lead to P. commutatus (Strobl) . It can be distinguished from the latter that has the mid femur broader than the fore femur, postpedicel dark in both sexes and tarsi extensively darkened apically. The new species has the mid femur narrower than the fore femur, postpedicel is yellow in male, brownish in female and the legs are yellow including the tarsi.

Figures

FIGURE 3. Platypalpus vercorsensis sp. nov., paratype male (photo Isabella Van de Velde).

FIGURE 4. Platypalpus vercorsensis sp. nov., paratype male, terminalia. A. Right epandrial lamella, lateral; B. Epandrium with cerci, dorsal view; C. Left epandrial lamella, lateral. Scale 0.1mm (image Patrick Grootaert).