Hybos thepkaisoni PLANT 2013, sp. nov.
Creators: name: PLANT, ADRIAN R.
Publisher: name: Zenodo
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Hybotidae
Hybos
Hybos thepkaisoni

description: Hybos thepkaisoni sp. nov.
(Figs 194–199, 278, 303)
Type material. HOLOTYPE ♂: THAILAND, Chiang Mai Province, Doi Phahompok National Park, Kiewlom2 / Montane Forest, 20°3.426'N 99°8.553'E, 2112 m, 21–28.ix.2007, Malaise trap, P.Wongchai [T6161](QSBG). PARATYPES: 10♂, 18♀, same data as holotype; 6♂, Doi Phahompok National Park, Kiewlom 1/ Montane Forest, 20°3.549'N 99°8.552'E, 2174 m, 21–28.ix.2007 (QSBG and NMWC).
Additional material. 2♂, 1♀, same data as holotype, 1–8.viii.2007; 1♂, 14–21.x.2007 (NMWC).
Etymology. Named in honour of Thepkaison, Queen of King Inthawayanonon, the last King of the last Lan-na tributory state of Chiang Mai.
Diagnosis. A black legged species with entirely pale setae on coxae and stylus subplumose on basal 0.8. The mid tibia is somewhat variable in colour but is normally very dark yellowish black and has 2 dorsal and 1 ventral setae very long (0.4X length of limb). The hind tibia is rather slender, slightly but distinctly swollen on distal 0.3. Mid metatarsus with strong erect basal seta. The thorax is rather strongly arched.
Description. Male: body length 4.0–5.0 mm. Head subshining black, dusted greyish, more strongly so about mouth edge behind eye; face black, vaguely yellowish black below; occipital setae black. Antenna black; postpedicel slightly paler, ovate in lateral view, 1.5–2.0X long as wide, with 1 small dorsal seta; stylus 6–8X long as postpedicel, black; subplumose on proximal 0.8, hairs curved, as long or slightly longer than stylus is deep; apical 0.2 bare. Mouthparts blackish, palpus narrow, with distinct dark hair near base and another subapically, otherwise short pilose. Thorax rather strongly arched, prescutellar area conspicuously flat, clearly defined from anterior part of scutum, rather large, steeply inclined towards base of scutellum and almost in line with mediotergite viewed in profile; ground colour black; postalar callus laterally, pleura vaguely about base of wing and outer face of postpronotal lobe very narrowly yellowish; dusted greyish, prescutellar area appearing somewhat yellowish in some lights; acr biserial, widely spaced, fine and hair-like; dc uniserial, similar to acr but posterior dc and acr before prescutellar area strong; npl rather strong, lower npl somewhat shorter than upper; pa strong; scutellum with 2 distinct dark sct and 4–5 paler fine marginal hairs. Legs rather slender, subshining black, thinly dusted greyish; ‘knees’ of all legs narrowly dark yellowish, especially about extreme base of T 3; trochanters paler than corresponding femora, often yellowish; T 2 variably dark blackish yellow, always rather paler than F 2; mid tarsus distinctly yellowish, especially on MT 2. Coxae with hairs and bristles mostly pale especially behind C 3 where conspicuously long and dense. F 1 with ventral fringe of pale hairs on basal 0.6 almost as long as limb is deep, virtually absent distally. F 2 very slightly narrowed on basal 0.5 viewed from above, with distinct fringe of anterior bristles on basal half; av and pv fringes not longer than limb is wide; small dark preapical setae anterodorsally and dorsally. F 3 moderately and quite evenly inflated, widest 0.6–0.7 from base; ventral spines numerous and long comprising 7–9 anteroventrals, most of which are conspicuously longer than limb is deep, and pv series of 9–11 rather shorter spines; pv fringe of short hairs becoming stronger distally, culminating in strong bristles on distal 0.3; 4 strong rather proclinate curved bristles anteriorly on apical 0.5 and 1 smaller bristle dorsoapically. T 1 with ventral fringe of pale hairs rather erect, no longer than limb is deep; dorsal fringe darker, rather proclinate, sparser, 1 much stronger but still fine bristle 3X long as limb is deep at 0.6 from base and 1 smaller bristle preapically; 1 very strong apical ad (0.5X length of MT 1) and several much smaller apical setae. T 2 with strong bristles 0.4X long as limb dorsally at 0.2 and 0.45 and ventrally at 0.5 from base; smaller but still strong bristles anteriorly and posterodorsally at 0.95 from base; apical circlet with 1 strong ventral bristle 0.7X long as MT 2. T 3 slightly but distinctly swollen on distal 0.3, with dorsal hairs erect, as long as limb is deep, 1 at extreme base and another preapically longer still; ventral hairs shorter, proclinate, merging into rather silvery yellow pile on apical half; 1 strong dorsal bristle 4–5X long as limb is deep at 0.6 from base and usually 1 smaller bristle slightly beyond; 1 short strong anterior preapical and longer apical av with 2 smaller bristles together forming apical circlet. MT 1 with 1 strong bristle (0.5X long as segment) near base and pair of longish fine hairs dorsally before tip. MT 2 with 1 strong seta near base and progressively smaller bristles at 0.5 from base and near tip. MT 3 with 1 ventral spine-like seta rather longer than surrounding yellowish pubescence, at least about base. Wing membrane distinctly yellowish brown, veins brown; stigma distinct, brown, long, reaching costa 0.8–0.9 distance between end of R 1 and R 2+3. Squamae with pale fringes. Halter white. Abdomen rather slender, black with somewhat bronze reflections, dusted greyish; bristly hairs mostly pale, longest and more numerous laterally and ventrally. Terminalia (Figs 194– 198) with black bristles; left epandrial lamella broad, inner margin somewhat concave basally; left surstylus (Fig. 196) long, rather sharply pointed with median swelling viewed from above but narrow and inwardly curved viewed from the side; right epandrial lamella enlarged distally on inner margin; right surstylus (Figs 197, 198) moderately long, viewed from above bluntly pointed with broad base, rather strongly curved in other views. Hypandrium (Fig. 195) with very short blunt apical process bearing numerous long bristles and twisted internally directed subapical process. Female. Similar to male but legs more slender, especially F 3 which is much less spinose, hardly inflated, widening gradually toward tip where 2X wide as at base. Ventral spines on F 3 practically uniserial, comprising 3–5 strong bristles 2–3X long as limb is deep on basal 0.7 and several smaller spines distally; pv fringe of pale hairs becoming longer on distal 0.5 but no strong bristles on distal 0.3; only 1 strong preapical anterior proclinate bristle; T 3 with 1 strong dorsal bristle 3–4X long as limb is deep at 0.6 from base and no smaller bristle slightly beyond; all tibiae with apical circlet of bristles weaker, especially on T 3 where only single dorsal and anterior apical bristles well developed. Abdomen broader and with shorter bristles than in male; terminalia (Fig. 199) with tergite 8 strongly sclerotized, black, densely dusted grey; sternite 8 strongly sclerotized, black, broad and shining basally, with narrow median extension posteriorly widening apically (narrow extension sometimes almost as broad as apical widening).
Comment. The mid tibia of Hybos thepkaisoni sp. nov. is variable in colour but is normally very dark yellowish black. Specimens with more distinctly yellowish mid tibiae might be confused with H. mangraii sp. nov. which also has a subplumose stylus but has the mid femur distinctly yellowish and the basal tergite of the abdomen is yellow laterally. Examples of H. thepkaisoni sp. nov. with dark mid tibia might be confused with H. tetricus sp. nov. or H. hylobates sp. nov. which also have two strong dorsal setae on the mid tibiae, a subplumose stylus and hind coxae with pale hairs. However, the postpedicel of H. thepkaisoni sp. nov. is shorter, the hind femur less inflated and males have shorter posteroventral hairs on the front metatarsus compared with either of these species. Hybos thepkaisoni sp. nov. is confined to moist evergreen forest on the summit slopes of Doi Phahompok (Daen Lao Range) in the far north of Thailand (Fig. 278). Adult emergence is more or less confined to between late September and October (Fig. 303).
description: Published as part of PLANT, ADRIAN R., 2013, The genus Hybos Meigen (Diptera: Empidoidea: Hybotidae) in Thailand, pp. 1-98 in Zootaxa 3690 (1) on pages 74-76, DOI: 10.11646/zootaxa.3690.1.1, http://zenodo.org/record/6329811