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

description: Hybos pisadaanus sp. nov.
(Figs 131–136, 267, 295)
Type material. HOLOTYPE ♂: THAILAND, Petchaburi Province, Kaeng Krachan National Park, Panernthung / km27/water pump, 12°49.151'N, 99°22.483'E, 970 m 5–12.ix.2008, Malaise trap, Sirichai & Chusak [T4377] (QSBG). PARATYPES: 24♂, 10♀, same data as holotype; 13♂, 12♀, Panernthung /km27, 12°49.302'N, 99°22.263'E, 950 m, 25.v.-1.vi.2009; 17♂, 12♀, Panernthung /km30, 12°49.598'N, 99°21.827'E, 5–12.ix.2008: 15♂, 3♀, Kamphaeng Phet Province, Mae Wong National Park, Chong Yen, 16°5.212'N, 99°6.576'E, 1306 m, 17– 24.ix.2007; 15♂, 3♀, 24.ix.-1.x.2007 (QSBG and NMWC).
Additional material. 57♂, 73♀ from Kaeng Krachan National Park in Petchaburi Province and 23♂, 10♀ from Mae Wong National Park in Kamphaeng Phet Province (QSBG and NMWC).
Etymology. From Thai pi-sa-daan = extraordinary, in reference to the predominantly yellow thorax which is unusual in species of Hybos.
Diagnosis. A distinctive species with clear yellow thorax, a well defined dark median stripe on the scutum and a large round black spot on the notopleural area. The legs are entirely yellow.
Description. Male: body length 2.5–3.0 mm. Head subshining black, thinly dusted; upper postocular setae black, short, becoming smaller and paler below; face yellowish black, becoming yellow near mouth edge. Antenna blackish; postpedicel ovate in lateral view, 2.0–2.5X long as wide, lacking dorsal seta; stylus 4–5X long as postpedicel, apical 0.4 abruptly narrower, paler in certain lights. Mouthparts dark yellowish, palpus very narrow, with 1 distinct yellowish apical seta. Thorax with ground colour clear yellow; scutum with broad brownish band not continued over prescutellar area, often narrower or fainter anteriorly; sharply defined black spot on notopleural area; prothoracic ‘collar’ dorsally and postpronotal lobe brownish; acr and dc fine, small, not continued over prescutellar depression; acr biserial, widely spaced (gap between rows> than distance between acr and dc rows); dc uniserial; posterior acr distinct, posterior dc very strong; line of fine setulae (surpra-alar or intra-alar seatae) between postpronotal lobe and supra-alar area; 1 strong and 2–3 weak npl; pa weak; scutellum with 2 distinct sct and several very fine marginal hairs. Legs clear yellow, tarsi becoming brownish distally. Coxae with pale setae. F 1 and F 2 with very fine yellowish hairs, longer than limb is deep. F 3 moderately inflated (Fig. 136), widest 0.6–0.8 from base, its ventral margin more or less linear in profile; ventral spines black, comprising strictly ventral series of ~15–18 more or less linearly arranged short strong setae with 3–4 stronger setae slightly displaced anteriorly; pv fringe black, with 2–3 setae ~0.8 from base longer than limb is deep; 2 distinct rather proclinate curving black bristles anteriorly near tip and another at ~0.5; otherwise with only shorter pale hairs. T 1 with short dark hairs dorsally from which can be distinguished 1 fine bristle at 0.5 and 1 stronger one dorsoapically; ventral hairs pale, longer, especially posteroventrally near tip where conspicuously long. T 2 with strong black bristles 0.7 X long as limb dorsally at 0.15 and anteroventrally at 0.5 from base; apical circlet with strong anterior bristle almost as long as MT 2. T 3 slightly swollen apically, dorsal pubescence longer distally; 1 short distinct yellowish dorsoapical bristle. Tarsomeres of anterior and mid legs slender, with fine dark apical bristles on proximal segments; tarsomeres 1 and 2 of posterior leg rather swollen, without conspicuous terminal bristles; MT 1 with very fine long pale hairs below, especially on basal 0.5; MT 2 lacking strong basal ventral bristle. Wing membrane tinged greyish brown; veins brown; stigma faint, brownish. Squamae with pale fringes. Halter white, with darker stem. Abdomen subshining brownish black, paler ventrally near base; all setae pale, becoming somewhat darker distally in certain lights. Terminalia (Figs 131–134) black, with epandrial lamellae rather compact in dorsal view, inner margins concave with median protuberances (Fig. 131). Left surstylus viewed laterally with large rectangular and narrower, pointed processes (Fig. 132). Right surstylus (Fig. 134), with 2–3 very strong, almost coalescent setae dorsoapically, the series continued but weaker along inner margin of right epandrial lamella. Hypandrium (Fig. 133) long, narrow, with paler process arising internally at apex and bearing three strong setae. Female. Differing from male as follows. F 3 with only ~8 ventral spines (~4 on basal 0.7 longer and more widely spaced than distal ~4); usually only 1 distinct curving black bristle anteriorly near tip; pv fringe weaker. F 1, F 2, T 1, T 2, MT 1 with ventral hairs shorter. Abdomen paler, with darker, shorter hairs. Terminalia (Fig. 135) with sternite 8 darker, narrowly oblong, not protuberant, rather weakly sclerotized, apically reflexed to vertical position, with very small sternite 10 between tip and base of cerci; tergite 8 narrow dorsally, wider laterally; tergite 10 very weakly scerotized, apparently divided dorsally.
Comment. Hybos pisadaanus sp. nov. is distinctive species unlike any other Hybos spp. occurring in Thailand. It has a diagnostically unique clear yellow thorax with a well defined dark median stripe on the scutum and a large round black spot on the notopleural area. The legs are entirely yellow. The species is known mostly from dry evergreen and lower hill evergreen forest biotopes at 735–1,306 m, only in the Tenasserim Hills of western Thailand (Fig. 267). All but one of 286 adults were trapped in the wet season between April and October with pronounced peaks of abundance in May and early June, and again in September (Fig. 295).
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 53-55, DOI: 10.11646/zootaxa.3690.1.1, http://zenodo.org/record/6329811