Hemerodromia zetalutea, Plant, Adrian R., 2015

Plant, Adrian R., 2015, Diversity of Hemerodromia Meigen, 1822 (Diptera: Empididae) in Thailand, the tip of a tropical iceberg?, Zootaxa 4039 (1), pp. 1-56 : 46-51

Hemerodromia zetalutea sp. nov.

( Figs 71, 72 , 97 )

Diagnosis. A yellow species with mediotergite darkened, prothoracic ‘collar’ dark medially. anterior spiracle narrowly but strongly emarginated above with small diagonal blackish mark; Posterior margin of scutum with well defined black ‘scutoscutellar eye’. Sct absent. Cell bm+dm short. Epandrium elongate with a row of minute inwardly directed dentate setulae dorsoapically.

Description. Male: Body length 2.5 mm; wing length 2.0 mm. Head. Black, dusted greyish, frons hardly paler; antenna and mouthparts pale whitish yellow, all setae pale; one pair reclinate ocl;1–2 pair of minute vtl, hardly distinguishable from sparse scattered minute hairs on vertex; postocular hairs minute but a few longer ones on lower occiput. Antenna with postpedicel ~1.8–2.0X long as wide, a few minute outstanding setulae subapically; stylus shorter, ~0.5X long as postpedicel; scape with distinct fine dorsal seta. Thorax. Dusted greyish. Ground colour yellow; mediotergite brownish black with yellow margin posterolaterally and prothoracic ‘collar’ very narrowly darkened medially; anterior spiracle narrowly but strongly emarginated above with small diagonal blackish mark; ‘scutoscutellar eye’ strongly defined, black; sutures between prothoracic ‘collar’ and anterior margin of scutum, at anterior margin of laterotergite and posterodorsal margin of meron black. All setae yellowish, minute, a pair of distinct npl, sct absent. Legs. Pale yellow. C1 ~1.2X longer than distance between C1 and C2, all setulae minute F1 ~ 1.2X long as C1, ~ 6X long as wide, evenly inflated, not constricted on proximal 0.3; femoral formula ~ 5–6/ 17/14–16/5, denticles black, rows converging apically; spines yellow, pv and av rows short, becoming somewhat longer proximally with most basal spine strong. T1 ~ 0.6–0.7X long as F1, evenly curved, ventral face shallowly concave; with two rows of ~ 14 similarly sized sharply pointed spinose setae ventrally; a short ciliation of distinct proclinate hairs dorsally on distal 0.2; ventroapical spur small but distinct with ventroapical erect black spinose seta arising from near its base. Mid and hind legs slender with only small pale setulae. Wing. Membrane almost clear, faintly darkened by brownish yellow microtrichia, hyaline basally. Veins yellowish, hyaline basally, M1+2 and cell bm+dm darker yellowish grey. Marginal setulae pale. R2+3 almost linear, joining C ~ 0.7X distance between end of R1 and R4; length of C between ends of R2+3 and R4 ~1.2X long as R4; R4 almost linear, only slightly S-shaped; R5 ~ 2X long as R4, almost linear; R4+5 fork distal to M1+2 fork by ~ 1.3–1.5X length of R4. M1 almost linear beyond base, convergent distally with R5; cell bm+dm short, ending at tip of R1. Halter yellowish white. Squama with margin greyish. Abdomen. Yellow with tergites 2–6 brown or blackish; all setae yellow, short but longer on distal segments, especially sternite 7. Terminalia. Black. Cercus elongate ( Figs 71, 72 ); about as long as epandrium; slightly expanded apically with two inwardly curving spinose setae at tip; a row of distinct bristly setae dorsally; basal lobe moderately broad in dorsal view, with numerous minute hairs dorsally. Epandrium elongate ( Fig. 71 ), rounded apically; a row of minute inwardly directed dentate setulae dorsoapically; pilose minute setulae on outer face, strongest posteroapically, absent at tip. Two narrow internal processes; upper process with one preapical and 2 short black apical inwardly directed apical dentate spines, lower process somewhat broader with cluster of fine setulae apically. Hypandrium broad, sparsely pilose with few distinct setae. Female: Similar to male. Terminalia brown with sternites 8 yellowish basally; a few distinct bristly setae laterally on tergite 8.

Type material. HOLOTYPE ♂, THAILAND: Petchabun Province, Khao Kho NP, mixed deciduous forest, 168 m, 16°39.589'N, 101°8.185'E, 19–26.i.2007, MT, Somchai Chachumnan & Saink Singtong [T1398]( QSBG). PARATYPES: 2♂, 1♀, same data as holotype, 12–19.i.2007, MT; 6–7.i.2007, 9–10.i.2007, pan trap ( QSBG & NMWC).

Additional material. 1♂, Kanchanaburi Province, Khuean Srinagarindra NP, Tha Thung-na /Chong Kraborg, 210 m, 14°38.123'N, 98°59.657'E, 16–23.x.2008, MT, Boonnam & Phumarin: 1♂, Chiang Mai Province, Doi Chiangdao Wildlife Sanctuary, Nature Trail, 491 m, 19°24.278'N 98°55.311'E, 7–14.x.2007, MT, Songkran & Apichart; 1♂, 1♀, Doi Chiangdao NP, Headquarters, 491 m, 19.40496°N, 98.92061°E, 2–9.xi.2007, 3–9.vi.2008, MT, S. Jugsu & A. Watwanich; 1♂, Queen Sirikit Botanic Garden, Semi-evergreen forest, 633 m, 18°54'00.0"N, 98°51'86.4"E, 2–9.ii.2007, MT, R. Sawkord & W. Srisuka; 1♂, Queen Sirikit Botanic Garden, deciduous forest, 620 m, 18°54'02.7"N, 98°51'78.6"E, 31.i.–2.ii.2007, flight interception trap, N. Buawangpong, J. Phasuk et al.; 1♂, Queen Sirikit Botanic Garden, Semi-evergreen forest, 704 m, 18°53'74.8"N, 98°51'86.4"E, 16–19.ii.2007, flight interception trap, J. Phasuk ( QSBG & NMWC).

Etymology. The specific epithet is a concatenation of the Latin luteus and the sixth letter of the Greek alphabet (zeta). It is used as a noun in apposition.

Remarks. The dark mark about the anterior spiracle can be absent and in such cases the dark areas around the sutures of the meron and laterotergite and the ‘scutoscutellar eye’ are less strongly defined. There are also small differences in male terminalia from different geographical areas; for example, in specimens from Chiang Mai Province the epandrium is slightly inflated apically with stronger setae compared with the type specimens from Petchabun Province. Hemerodromia zetalutea sp. nov. is widely distributed in Thailand with records from the north (Chiang Mai) northeast (Petchabun) and western (Kanchanaburi) regions ( Fig. 97 ). It has been found in a variety of lowland (168–627 m) deciduous and evergreen dry forest types. All but one specimen were captured between October and February during the cool dry season.

Figures

FIGURES 71 – 72. Male terminalia of Hemerodromia zetalutea sp. nov. 71, lateral view of terminalia; 72, dorsal view of cerci. Abbreviations: cer = cerci, epa = epandrium, hyp = hypandrium.

FIGURES 91 – 98. Distribution of Hemerodromia spp. in Thailand at a resolution of 0.25 ° of latitude and longitude with symbols scaled to 0.5 °. 91, H. ocellata sp. nov.; 92, H. oriens sp. nov.; 93, H. phahompokensis sp. nov.; 94, H. songsee sp. nov.; 95, H. systoechon sp. nov.; 96, H. yunnanensis Yang & Yang; 97, H. zetalutea sp. nov.; 98, Species richness of Hemerodromia spp. in Thailand at a resolution of 1 ° with symbols plotted at same resolution.