Platypalpus layiaphilus Shamshev & Grootaert

Shamshev, Igor & Grootaert, Patrick, 2012, Proposed change in status of the Nearctic genus Charadrodromia Melander (Diptera: Hybotidae, Tachydromiinae), with description of four new species, Zootaxa 3525, pp. 35-50 : 43-44

Platypalpus layiaphilus Shamshev & Grootaert sp. nov.

( Figs. 15–17 )

Type material: HOLOTYPE, 3 labelled: U.S.A.: CALIFORNIA: / Mendocino County, Hop- / land, University of California Hopland / Field Station / 20 May 1986 / Paul H. Arnaud, Jr.; Two Empididae in one / flower of Layia platy- / glosa ssp. campestris / Keck (det. B. Bartholomew) / seepage along gravel / road, midday; Holotype [pink]; Holotype / Platypalpus layiaphilus / Shamshev et Grootaert sp. nov. ( CAS). PARATYPE. 1 3, same data as in holotype ( CAS).

Recognition. This species is distinguished by palpus and antenna brown; postpedicel nearly as long as wide; fore tarsi yellow; dorsocentrals arranged in 2–3 irregular rows.

Description. Body length 1.3–1.4 mm; wing length 1.4 mm. Male. Head black in ground-colour. Frons broad, finely brownish grey pollinose, rather subshining, widened toward ocellar tubercle. Face narrow, concolorous with frons, denser pollinose. Ocellar tubercle with 2 long brownish proclinate anterior and 2 short lateroclinate posterior bristles. Two pairs of long brownish verticals. Occiput densely greyish pollinose, with numerous brownish yellow to pale setae of different lengths. Antenna brown; postpedicel, short, nearly as long as wide (1.3X in holotype); stylus 2.0X as long as postpedicel. Proboscis brown. Palpus small, brown, with several fine setae of different lengths.

Thorax black in ground-colour, entirely finely greyish pollinose, somewhat denser on pleurae, katepisternum without shining spot; with yellowish to pale setation. Postpronotal lobe with 1 long inclinate bristle and several short setae. Mesonotum with 1 presutural supra-alar, 2 notopleurals, 1 postalar and 4 scutellar bristles (apical pair very long and cruciate, lateral pair short); additionally, notopleural depression with several setulae and similar setulae present on supra-alar space; acrostichals arranged in 2 irregular rows, short, distinctly separated from dorsocentrals by bare space; dorsocentrals arranged in 2–3 irregular rows, short, 2 prescutellar pairs long.

Legs entirely yellow to dusky yellow. Fore femur thickened, mostly covered with short setae, bearing rows of yellow anteroventral and posteroventral setae becoming longer basally. Fore tibia slightly thickened. Mid femur somewhat narrower than fore femur; with short black spinule-like anteroventral and longer posteroventral setae. Mid tibia without apical spur, with several stronger black setulae subapically. Hind femur with short anteroventral setae. Hind tibia unmodified, bearing 1 short anterodorsal subapical seta, otherwise covered with short setulae.

Wing hyaline, with brownish yellow to pale yellow veins. One long brown costal bristle. Veins R4+5 and M straight and parallel near wing margin; CuA2 somewhat concave; cells br and bm contiguous, rather short, bm broader than br. Squama yellow, with pale setae. Halter pale yellow.

Abdomen brown in ground-colour, finely greyish pollinose, viewed dorsally rather subshining; covered with short pale setae. Terminalia ( Figs. 15–17 ) rather large, concolorous with abdomen; left cercus broadened apically, with several unmodified setae of different lengths; right cercus digitiform, narrow, somewhat longer than left cercus, with several unmodified setae of different lengths; left epandrial lamella subrectangular basally, produced with finger-like projection apically and mid-ventral tubercle; covered with numerous setae of different lengths on apical part and with several long setae sitting on ventral tubercle; right epandrial lamella subconical, with numerous unmodified setae of different lengths; right surstylus undifferentiated from epandrium.

Female. Unknown.

Etymology. The name of the new species reflects that it was collected in a flower of Layia platyglosa ssp. campestris Keck.

Distribution. USA (California).

Remarks. Platypalpus layiaphilus sp. nov. is most similar to P. cummingi sp. nov. The main differences between these species are given below in the key.

Figures

FIGURES 15 – 17. Platypalpus layiaphilus sp. nov., male. 15. right epandrial lamella, lateral view. 16. cerci and epandrium, dorsal view. 17. left epandrial lamella and left cercus, lateral view.