Dolichocephala srisukai, Sinclair & Plant, 2017

Sinclair, Bradley J. & Plant, Adrian R., 2017, Dolichocephala Macquart of Thailand (Diptera: Empididae: Clinocerinae), Zootaxa 4358 (3), pp. 551-568 : 559-562

Dolichocephala srisukai sp. nov.

( Figs 6 , 13, 14, 22, 24)

Type material. HOLOTYPE, ♂ labelled: “THAILAND: Chiang Mai Prov./ Doi Phahompok NP; 2175 m / hill evergreen forest; 16.vii.2006 / 20°03′58.8″N 99°08′.35.3″E/ herb covered stream/ A.R. Plant leg.”; “HOLOTYPE/ Dolichocephala / srisukai / Sinclair & Plant [red label]” (QSBG). PARATYPES: THAILAND. Chiang Mai Province: Doi Inthanon NP, summit marsh, 18°35.361′N 98°29.157′E, 2500 m, MT, 26.x.–2.xi.2006, Y. Areeluck leg. T380 (1 ♀, CNC); Doi Inthanon NP, Kew Maepan Trail, 18°33.162′N 98°28.81′E, 2200 m, MT, 29.iv.– 6.v.2007, Y. Areeluck leg. T1853 (2 ♂, 1 ♀, CNC); Doi Inthanon NP, summit forest, 18°35.361′N 98°29.157′E, 2500 m, MT, 2–9.viii.2006, Y. Areeluck leg. T125 (6 ♂, 4 ♀, CNC); Doi Inthanon NP, summit marsh, 18°35.361′N 98°29.157′E, 2500 m, MT, 22.vii.–2.viii.2006, Y. Areeluck leg. T118 (8 ♂, 7 ♀, CNC); Doi Inthanon NP, summit marsh, 18°35.361′N 98°29.157′E, 2500 m, MT, 2–9.viii.2006, Y. Areeluck leg. T124 (3 ♂, 1 ♀, CNC); Doi Inthanon NP, summit marsh, 18°35.361′N 98°29.157′E, 2500 m, MT, 16–24.viii.2006, Y. Areeluck leg. T184 (1 ♂, CNC); Doi Inthanon NP, summit marsh, 18°35.361′N 98°29.157′E, 2500 m, MT, 8–15.vii.2006, Y. Areeluck leg. T64 (2 ♂, CNC); same data as holotype (14 ♂, 32 ♀, QSBG).

Additional material. THAILAND. Chiang Mai Province: Doi Inthanon NP, summit (Angka) 18.58892°N 98.48481°E, 2545 m, Rhododendron scrub in moist hill evergreen forest at edge of Sphagnum bog, MT, 1.iv.– 2.v.2014, 29.v.–1.vii.2014, 30.vii.–27.viii.2014, 27.viii.–29.ix.2014, Srisuka & Plant leg., QSBG- 2014–80, 2014– 213, 2014–234, 2014–155 (9 ♂, 5 ♀); Doi Inthanon NP, summit (behind office), 18.58689°N 98.48723°E, 2534 m, moist hill evergreen forest, MT, 1.iv.–2.v.2014, 2–29.v.2014, 27.viii.–29.ix.2014, 4.xi.–1.xii.2014, 1.xii.2014 – 5.i.2015, Srisuka & Plant leg., QSBG- 2014–78, 2014–125, 2014–285, 2014–79, 2014–233, 2014–322 (17 ♂, 8 ♀); Doi Inthanon NP, Kiew Maepan, 18.55817°N 98.48103°E, 2210 m, moist hill evergreen forest, MT, 30.vii.– 27.viii.2014, 1.iv.–2.v.2014, Srisuka & Plant leg., QSBG- 2014–82, 2014–83, 2014–214, 2015–215 (27 ♂, 27 ♀); Doi Phahompok NP, route to summit trap 1, 20.05042°N 99.14406°E, 2036 m, moist hill evergreen forest, MT, 28.i.–28.ii.2014, Srisuka & Plant leg., QSBG- 2014–67 (1 ♀); route to summit trap 3, 20.05492°N 99.14239°E, 2105 m, moist hill evergreen forest, MT, 28.i.–28.ii.2014, 1–30.iv.2014, 30.iv.–29.v.2014, Srisuka & Plant leg., QSBG- 2014–69, 2014–140, 2014–143 (2 ♂, 1 ♀).

Recognition. This species is recognized by the long auxiliary crossvein connecting R4 to R2+3, longer than base of R4, R2+3 short ending in costa proximal to base of R4, and phallus stout, straight, without distiphallus.

Description (wing length 2.2–2.5 mm). Male. Head: Slender, tapered ventrally. Clypeus and face with greyish pruinescence, extending dorsally as narrow stripe around ocellar triangle and joining to form “V” on upper occiput. Ocellar triangle with pair of stout upturned setae. Antenna dark brown.

Thorax: Scutum dark brown with faint bluish pruinescent medial stripe extending to prescutellar depression. Pleura with whitish pruinescent stripe from just above fore coxa straight posteriorly to below posterior spiracle. Several very minute acrostichals anterior to first dc; 4 dc; 1 pprn; 1 presut spal; 1 upper npl and numerous short setulae; 1 fine, short pal; 2 short, slender sctl, half length of dc. Laterotergite with several brownish setulae.

Legs: Fore coxa and femora yellow, remaining segments darkening apically; mid and hind coxae dark brown, concolourous with pleura.

Wing (Fig. 14): Narrow; infuscate; single long basal costal seta present; base of R4 straight and near at right angle to R5; base of cell r4 truncate; R4 sinuous, with long auxiliary crossvein connecting to R2+3, longer than base of R4; R2+3 short ending in costa proximal to base of R4; irrorations distinct: base of cell r1 with slender spot; two large spots in cell r2+3 and occasionally 2 faint spots (proximal section); one spot each in cells r4, m1, m2 and m4; cell r5 with 3 spots at apex, below R4 and near base; cell dm with 1 spot near apex and 1 spot near base; cell bm white. Halter brown.

FIGURES 13–16. Habitus and wing images of Dolichocephala spp. in Thailand, lateral view. 13. D. srisukai sp. nov., male; 14. D. srisukai sp. nov., wing; 15. D. thailandensis sp. nov., female; 16. D. thailandensis sp. nov., wing. Scale bars = 1 mm. Abbreviations: m1,2,4—first, second, fourth medial cells; R2+3—second branch of radius; R4—third branch of radius.

Abdomen: Sclerites dark brown, concolourous with thorax; lateral margins of tergites shiny. Terminalia ( Fig. 6 ): Hypandrium subtriangular, with 3 lateral setae. Phallus straight, stout, well sclerotized; apex expanded with forked, paired of upper pointed processes; membranous sac medially; lower apical process joined medially; without distiphallus. Ejaculatory apodeme crescent-shaped. Epandrium subtriangular with several long, stout marginal posterior setae. Clasping cercus strongly tapered to narrow apex, arched medially; outer face with long setae; inner face with short tooth-like projection bearing several setae. Cercal plate with 2 long setae. Lobe of subepandrial sclerite absent, not projecting. Surstylus elongate, digitiform, subequal in length to clasping cercus; apex somewhat expanded, rounded, bearing 2–3 pairs of setulae.

Female. Similar to male. Cercus slender, more than 2X longer than basal width.

Etymology. This species is named in honour of Wichai Srisuka (QSBG), who has done so much to facilitate recent mass sampling programs in Thailand and without him, we would have very few empidoids available for study.

Distribution. This species is restricted to moist hill evergreen forest biotopes at or above 2,000 m on the summit areas of the mountains Doi Inthanon (Thanon Thongchai Range) and Doi Phahompok (Daen Lao Range) in northern Thailand ( Fig. 22 ).

Remarks. Adults are mostly active in April and during July / August, at the start and end of the monsoon, respectively ( Fig. 24 ).

Figures

FIGURE 24. Phenology of adultabundance of Dolichocephala srisukai sp. nov. caught inMalaise traps (MT) on Doi Inthanon and Doi Phahompok and caught by sweep netting on Doi Phahompok.

FIGURES 5–7. Male terminalia of Dolichocephala spp. in Thailand, lateral view. 5. D. longicerca sp. nov.; 6. D. srisukai sp. nov.; 7. D. thailandensis sp. nov. Scale bars = 0.1 mm. Abbreviations: cl cerc—clasping cercus; distph—distiphallus; phphallus.

FIGURES 17–23. Distribution of Dolichocephala spp. in Thailand at a resolution of 0.25° of latitude and longitude with symbols scaled to 0.5°. 17. D. bicolor sp. nov.; 18. D. curvata sp. nov.; 19. D. immaculata sp. nov.; 20. D. incus sp. nov.; 21. D. longicercasp. nov.; 22. D. srisukai sp.nov.; 23. D. thailandensis sp. nov.