Platypalpus obscuroides Bartak & Grootaert, 2021

Kanavalova, Liliana, Grootaert, Patrick, Kubik, Stepan & Bartak, Miroslav, 2021, Four new West Palaearctic species and new distributional records of Hybotidae (Diptera), ZooKeys 1019, pp. 141-162 : 141

Platypalpus obscuroides Bartak & Grootaert sp. nov. Fig. 9

Type material.

Holotype ♂, Slovakia: Muráňska planina NPR, Šarkanica, 540 m, MT, 48°42'46"N, 19°59'52"E, M. Tkoč, 6.vi.-6.vii.2018 (CULSP); Paratypes: 1♂, same data as holotype; 3♂, 2♀, same locality, 6.vii.-7.viii.2018 (dissected RBINS); 1♀, same locality, 48°42'46"N, 19°59'56"E, 580 m, 10.viii.-5.x.2017; 2♀, Muráňska planina NP, Hrdzavá dolina, 540 m, MT, 48°44'52"N, 20°01'04"E, J. Roháček, 21.vi.-6.viii.2013 (all CULSP).

Diagnosis.

A species of the Platypalpus albiseta group with mesonotum and anepisternum entirely microtrichose. Katepisternum with a large shiny spot dorsally, rather stripe-like, reaching from anterior to posterior margins. Meron entirely microtrichose except small subshiny spot ventrally. The new species is similar to P. obscurus (von Roser, 1840) except for the much larger male terminalia and the above-mentioned large lustrous spot on the katepisternum.

Etymology.

The species name refers to the similarity with P. obscurus .

Description.

Male head black, entirely grey microtrichose including gena, only clypeus shiny. Frons very narrow (at lower two thirds as wide as anterior ocellus, at narrowest point less than 0.02 mm wide), widening both ventrally (0.06 mm above antennal bases) and dorsally (0.05 mm at level of front ocellus), densely covered with relatively long microtrichia. Slightly prominent ocellar triangle with two pairs of black setae, anterior pair about 0.10 mm long, posterior pair slightly shorter. Occiput microtrichose, subshiny (postocular area with somewhat longer microtrichia giving silvery appearance), with sparse dark setae dorsally and several longer and paler setae ventrally. One pair of long black vertical setae somewhat longer than anterior ocellars and inserted wide apart (0.17 mm). Face very narrow (0.02-0.03 mm), only slightly widening below. Clypeus long, shiny, gena microtrichose. Palpus brown, ovoid and very small (0.07 mm long), with several pale brown setae at tip, one of them longer than palpus. Labrum shiny brown, two thirds as long as head height. Antenna brown with white stylus. Scape without setae, 0.02 mm long; pedicel (0.05 mm long) with circlet of short black setae; postpedicel long (0.32-0.40 mm), narrow (6 × longer than wide), with relatively long setulae on both sides, equally narrowing towards tip; stylus half as long as postpedicel (0.16-0.22 mm long), white, dark at extreme base. Thorax black to brownish black, microtrichose (except lustrous extreme anterior part of mesoscutum and part of katepisternum), in anterior view with broad velvety-brown stripe below acrostichals and in posterior view with two silvery lines between acrostichals and dorsocentrals. Katepisternum with large shiny spot dorsally, rather stripe-like, reaching from anterior to posterior margins, lower half microtrichose. Meron entirely microtrichose except small subshiny spot ventrally. Chaetotaxy: antepronotum with several short pale setulae on each side, postpronotum with scarcely differentiated setae, 1 notopleural, 1 short postalar. Acrostichals inclinate, in 6-8 irregular rows, only indistinctly separated from nearly uniserial dorsocentrals, both short (about 0.07 mm long), one prescutellar seta; 2 pairs of scutellars, outer pair much shorter.

Legs including coxae brown to black, fore coxa and base of fore femur more or less yellowish, some specimens with paler mid coxa or basal part of mid and hind femora. Setae both pale and brown. Fore femur with two ventral rows of setae (somewhat golden-brown under some angles of view) almost as long as diameter of femur. Fore tibia strongly spindle-shaped, dilated (at broadest point twice wider than before apex), densely set with ventral pubescence as long as tibia depth. Mid femur nearly as wide as fore femur, slightly swollen in basal quarter only, distal part thin, with anteroventral row of black spinules, long about base, with several anteroventral setae similarly longer about base, posteroventral spines somewhat longer than anteroventral spines; short dense white pubescence between anterior and posterior rows of spinules; 4-6 dark posteroventral setae as long as femur depth, inserted almost in same line as spines. Hind femur nearly as wide as mid femur, with ventral row of pale setulae about as long as femur depth. Hind tibia ventrally with whitish setulae as long as tibia depth. Wing brown-infuscated especially in anterior half, entirely microtrichose. Basal costal seta brown, long. Subcosta incomplete, ending free; crossveins contiguous; CuA2 strongly recurrent; anal vein distinct throughout; vein M1 slightly S-shaped; C ends at tip of M1 vein. Halter brown, calypter black in proximal part and brownish-yellow in distal half, fringe pale. Abdomen brown, genital lamellae contrastingly black. Tergites thinly microtrichose, subshiny, sternites microtrichose. Setae mostly pale, short, those on last segment longer. Terminalia as in Fig. 9A-D , very large (total length nearly 0.70 mm). Apices of both cerci pointed. Right epandrial lamella with single, acute, bent tip (Fig. 9A ). Apex of left epandrial lamella rather shorter than in P. obscurus . Length: body 2.4-2.7 mm, wing 2.5-3.3 mm.

Female. Very similar to male in all details except the following: abdomen more microtrichose and segment 8 very long (about 0.60 mm long including ventral prolongation, longer than four preceding segments combined), shiny black at side, narrow dorsal stripe not sclerotized. Length: body 2.9-3.5 mm, wing 2.7-3.0 mm.

Remarks.

Platypalpus obscuroides (POI) is very similar to P. obscurus (POS). However, it differs in the length of the stylus, which in the new species (POI) is about half as long as the postpedicel, while in POS it is nearly as long as the postpedicel. Further differences are: katepisternum in POI widely lustrous up to its hind margin, whereas with only a small oval lustrous patch not reaching hind margin of katepisternum and narrowly lustrous posterior margin in POS. Male terminalia: left cercus wider and as long as right cercus in POS (Fig. 10C ), versus both cerci pointed and right cercus longer in POI (Fig. 9D ); apex of right epandrial lamella bent in POI (Fig. 9A ), versus as two claw-like projections in POS (Fig. 10D ). The female of POI has a shiny abdominal segment 8, while it is almost entirely microtrichose in POS.

Distribution.

Slovakia.

Figures

Figure 9. Platypalpus obscuroides sp. nov., male terminalia A epandrium, from right side B apex of right epandrial lamella C epandrium and cerci, dorsolateral view D cerci, dorsal view. Abbr. lc: left cercus; lel: left epandrial lamella; ph: phallus; rc: right cercus; rs: right surstylus. Scale bars: 0.1 mm.

Figure 10. Platypalpus obscurus (von Roser), male terminalia A dorsal view of apex of right epandrial lamella and left cercus B lateral view of apex of right epandrial lamella C epandrium, dorsal D epandrium, left lateral. Scale bars: 0.1 mm.