Tachydromia phanensis, Shamshev, Igor & Grootaert, Patrick, 2008

Shamshev, Igor & Grootaert, Patrick, 2008, New and little-known species of the genus Tachydromia Meigen (Diptera, Hybotidae) from Thailand, Zootaxa 1830, pp. 21-36 : 23-25

Tachydromia phanensis sp. nov.

( Figs 1–3 , 24 )

Diagnosis. Palpus yellow. Legs with complicated colour pattern; fore femur largely brownish. Wing almost entirely finely brownish infuscate, paler near base and hyaline on subapical space, brown along anterior margin. Halter with brown knob. Male: fore tibia unmodified.

Description. Male. Wing 1.8–1.9 mm. Head black in ground-colour. Eyes extending beyond ocellar tubercle. Frons subshining, slightly widened toward ocellar tubercle, above antennae nearly 1.5 times as broad as anterior ocellus. Ocellars minute. Occiput largely finely pollinose, narrowly shining in upper part beyond eyes; with 2 short strong black setae in upper part, 2 similar setae on middle part laterally and numerous pale hair-like setae near neck and on lower part. Basal antennal segments brownish; postpedicel paler, brownish yellow, short, elongate oval; stylus very long, brownish, short pubescent. Proboscis largely brown, yellow proximally. Palpus unmodified, short, elongate oval, yellow, with 1 long black and 1 subequal but thinner brownish yellow subapical setae and 4–5 brownish yellow short setae basally.

Thorax dark brown in ground-colour, largely shining; prominent setae black; prothoracic sclerites (except postpronotal lobe) pollinose. Postpronotal lobe large, lacking conspicuous setae. Mesonotum with 2 notopleural (posterior one longer) and 2 scutellar setae; Acrostichals and dorsocentrals minute, the former arranged in 2–3 irregular rows, lacking on prescutellar depression, the latter uniserial.

Legs long, with complicated colour pattern; fore coxa almost entirely brown (yellow apically), mid coxa almost entirely yellow (brownish basally), hind coxa entirely yellow; all trochanters yellow; fore femur brownish near extreme base, broadly in apical half posteriorly and dorsally (except extreme apex), with narrow brownish anterior patch basally, otherwise yellow; mid femur almost entirely brownish, somewhat paler dorsally and near extreme base and apex; hind femur pale yellow on basal 1/5, otherwise dark brown; fore and mid tibiae brownish, hind tibia brown on basal 1/3–1/2, otherwise yellow; all tarsi brownish (hind basitarsus slightly paler basally). Coxae mostly with pale hair-like setae of different length, hind coxa with 1 strong black curved seta anteriorly; pale hair-like setae present between fore and mid coxae. Fore femur strongly thickened, mostly with minute anteroventral and posteroventral setulae, bearing 4–5 stronger spinule-like anteroventral setulae near middle. Fore tibia slightly swollen, with inconspicuous setation. Mid femur slender, with anteroventral and posteroventral very short (the latter longer) spinule-like setae becoming somewhat longer toward base of femur. Mid tibia slender, lacking prominent bristles with some ventral spinule-like setulae. Hind femur slender, with rows of short strong anteroventral and posteroventral setae becoming shorter and thinner basally. Hind tibia slender, lacking prominent bristles, with narrow pointed posterior apical comb. Tarsi of all legs unmodified.

Wing ( Fig. 24 ) normally developed, rounded at apex, with typical venation for the genus; largely finely brownish infuscate, paler near base and hyaline on subapical space, brown along anterior margin. One short basal costal seta present. Vein R1 meeting costa beyond wing midway. Proximal section of vein R4+5 considerably longer than Rs. Vein R2+3 straight. Veins R4+5 and M1+2 parallel toward wing-apex. Crossveins r-m and bmcu separated. Cells br and bm extending to wing midway. Halter with pale stem and brown knob.

Abdomen with segment 1 pale, otherwise brown, covered mostly with scattered, short, black setulae; segments 7 and 8 with moderately long setae. Terminalia ( Figs 1–3 ) large, dark brown, elongate oval. Right cercus long, tapered apically, covered with numerous unmodified setae of different length, bearing 1 very long apical seta. Left cercus about half length of right cercus, pointed apically, covered with scattered short setae. Right epandrial lamella subtriangular (viewed laterally), with large rounded ventral process in subapical part, bearing numerous setae of different lengths. Right surstylus long, narrow, bent inward, with several unmodified setae of different length apically and on inner side. Left epandrial lamella subtriangular, bearing several unmodified setae of different lengths. Left surstylus short, subrectangular, with 1 very long subapical seta, several strong moderately long setae on upper margin and some short setae apically.

Female. Fore femur more extensively brownish, lacking stronger anteroventral spinulae near middle. Hind femur lacking prominent anteroventral and posteroventral setae. Otherwise as in male. Cercus brownish, rather short.

Material examined. Holotype male: THAILAND Chaiyaphum prov., Pa Hin Ngam NP Tung Dok Grajeaw 15°38.208'N 101°23.556'E 720 m Malaise trap 6–12.vii.2006 Kratae Sa-nog & Buakaw Adnafai leg. T331.

Paratypes: 1 male, 1 female, THAILAND Sakon Nakhon prov., Phu Phan NP Behind office 17°03.488'N 03°58.497'E 318 m Malaise traps 8–14.vii.2006 Sailom Tongboonchai leg. T199; 1 female, Chiang Mai prov., Doi Inthanon NP Vachiratharn Falls 18°32.311'N 98°36.048'E 700 m Malaise trap 12–19.x.2006 Y. Areeluck leg. T366; 1 female, Sakon Nakhon prov., Phu Phan NP Behind office 17°03.521'N 103°58.450'E 322 m Malaise traps 27.vii–2.viii.2006 Winlon Kongnara leg. T207; 1 female, Chaiyaphum prov., Pa Hin Ngam NP creek at Tung Dok Grajeaw 15°38.391'N 101°23.609'E 750 m Malaise trap 19–24.vii.2006 Kratae Sa-nog & Buakaw Adnafai leg. T335.

Derivatio nominis. The species is named after one of the National Parks where the species was found: Phu Phan NP in Sakon Nakhon province.

Distribution. Thailand.

Remarks. The new species is closely related to T. phu sp. nov. sharing similar setation of the left surstylus (1 very long and several strong bristles). The main distinguishing features between these species are given in the key.

Figures

FIGURES 1 – 3. Tachydromia phanensis sp. nov. 1. hypopygium, ventral view. 2. the same, dorsal view. 3. left surstylus, lateral view. a: anus; HY: hypandrium; LEL: left epandrial lamella; LS: left surstylus; RC: right cercus; REL: right epandrial lamella; RS: right surstylus; vp: ventral process of right epandrial lamella. Scale 0.1 mm.

FIGURES 24 – 31. Wings. 24. Tachydromia phanensis sp. nov. 25. Tachydromia phu sp. nov. 26. Tachydromia tigeri sp. nov. 27. Tachydromia ocellata sp. nov. male. 28. Tachydromia luang Shamshev, Grootaert. 29. Tachydromia monocercus sp. nov. 30. Tachydromia doi sp. nov. 31. Tachydromia ocellata sp. nov. female.