Hemerodromia etalutea, 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 : 26-27

Hemerodromia etalutea sp. nov.

( Figs 37–39 , 84 )

Diagnosis. A species with yellow thorax with only sutures about laterotergite blackish. Sct present. Cell bm+dm long. Wing veins entirely yellow. Abdomen with tergite 2 yellow. Epandrium strongly concave on dorsal margin.

Description. Male: Body length 2.6–3.0 mm; wing length 2.5 mm. Head. Black, dusted greyish; frons paler, brownish in front of ocelli, becoming whitish near base of antenna; antenna and mouthparts pale whitish yellow, all setae pale; one pair proclinate ocl; postocular setae uniseriate, merging above with ~1–2 pairs small vtl and several fine setulae on vertex; frontal setulae apparently absent. Antenna with postpedicel ~2.5–3.0X long as wide, a few minute outstanding setulae subapically; stylus shorter, ~0.4–0.45X long as postpedicel; scape with distinct fine dorsal seta. Thorax. Dusted greyish. Ground colour clear yellow including mediotergite and prothoracic ‘collar’; only sutures about laterotergite blackish. All setae yellowish; minute apart from a pair of distinct sct and one npl. Legs. Pale yellow. C1 ~1.2X longer than distance between C1 and C2, a few distinct setulae dorsally and apically. F1 ~ 1.2X long as C1, ~ 6X long as wide, evenly inflated, hardly constricted on proximal 0.3; femoral formula ~ 7– 8 /18–19/18–19+1–2/6–8, denticles black, rows converging apically; spines yellow, pv and av rows rather short, 0.3–0.5X long as limb is deep, becoming somewhat longer proximally with basal spine of pv row much stronger. T1 ~ 0.6–0.7X long as F1, evenly curved, ventral face shallowly concave; with one row of ~ 15 sharply pointed spinose setae ventrally; ventroapical spur extremely small with strong erect black spinose seta arising from near base; a ciliation of short setulae dorsally on distal 0.3. Mid and hind legs slender with only small pale setulae. Wing. Membrane with yellow microtrichia but hyaline basally. Veins yellow, paler near base of wing. Marginal setulae pale. R2+3 almost linear, joining C ~ 0.6X distance between end of R1 and R4; length of C between ends of R2+3 and R4 ~1.8–2.0X long as R4; R4 slightly S-shaped, angle with R5 at extreme base ~ 85°, becoming ~70–80° thereafter, joining C at ~ 85°. R5 ~ 2.0–2.5X long as R4, almost linear; R4+5 fork distal to M1+2 fork by ~ 1X length of R4. M1 slightly curved, convergent distally with R5; cell bm+dm long, ending beyond tip of R1. Halter yellowish white. Squama with margin yellowish. Abdomen. Yellow with tergites 3–5 and 8 blackish; tergite 2 sometimes faintly darker medially. Tergite 8 with dark bristly setae on posterior margin; tergite 7 with a few smaller yellow setae on disc. Terminalia. Cercus of complex structure; slightly shorter than epandrium; narrow distally with tip upturned in lateral view ( Fig. 37 ); 2 small subtriangular dorsal process on proximal 0.5 with a short row of very fine setulae adjacent on outer face ( Figs 37, 38 ). Epandrium with upper margin distinctly and rather abruptly curved beyond middle; a cluster of 3–4 strong setae apically. Surstylus present, not reaching beyond tip of epandrium; apically inflated with several strong black peg-like modified setae around tip ( Fig. 39 ). A pale yellowish (almost transparent) dorsoapically pointed process emerging slightly beyond tip of epandrium. Hypandrium small, angular, subquadrate with a few distinct setae proximally. Female: Similar to male; terminalia blackish.

Type material. HOLOTYPE ♂, THAILAND: Nakhon Si Thammarat Province, Namtok Yong NP, TV aerial, 966 m, 8°14.262'N, 99°48.289'E, 15–22.x.2008, MT, Paiboon [T4226]( QSBG). PARATYPES: 3♂, 2♀, same data as holotype ( QSBG & NMWC).

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

Remarks. Hemerodromia etalutea sp. nov. can be distinguished from other species with an unmarked yellow scutum by having the mediotergite clear yellow and the wing with both veins and membrane yellow but confirmation of identification requires examination of male terminalia. The species is only known from Nakhon Si Thammarat Province in southern Thailand ( Fig. 84 ) at mid elevation (966 m) in October.

Figures

FIGURES 37 – 39. Male terminalia of Hemerodromia etalutea sp. nov. 37, lateral view of terminalia; 38, dorsal view of cerci; 39, apex of surstylus. Abbreviations: cer = cerci, epa = epandrium, hyp = hypandrium, sur = surstylus.

FIGURES 82 – 90. Distribution of Hemerodromia spp. in Thailand at a resolution of 0.25 ° and symbols sized to 0.5 ° of latitude and longitude. 82, H. demissa sp. nov.; 83, H. epsilutea sp. nov.; 84, H. etalutea sp. nov.; 85, H. flaviventris Yang & Yang; 86, H. furcata Grootaert, Yang & Saigusa; 87; H. fusca Yang & Yang; 88, H. gammalutea sp. nov.; 89, H. isochita sp. nov.; 90, H. namtokhinpoon sp. nov.