Agadasys hexablepharis Whittington, 2000

Chen, Xiaolin & Whittington, Andrew E., 2006, A new species in the genus Agadasys Whittington (Diptera: Platystomatidae, Plastotephritinae) from China, Zootaxa 1358, pp. 59-66 : 61-65

Agadasys hexablepharis Whittington, 2000

Agadasys hexablepharis Whittington, 2000a: 338 ( Thailand) . Holotype in BPBM.

Diagnosis: Ground colour predominantly pale creamy contrasting with grey-brown and dark brown markings on scutum and pleura and mottled on abdominal tergites; head without brown markings adjacent to ocellar triangle; setae on R1 as long as the distance across the bases of four setae; sclerotized portion of glans, in male postabdomen, covering more than 60% of apex, lateral lobes well defined on side corresponding to basal caecum; acrophallus evenly curved.

Length of body 4.1–5.3 mm; of wing 4.5–5.1 mm.

Material examined: China: 1 male, Yunnan, Menglong, 7.iv.1958, [no collector named] (IZCAS).

Distribution: Thailand; China (Yunnan), India [sic, actually Bangladesh], Vietnam. In error, Whittington (2000a) stated that one of the paratype locations was Sylhet, in India, as stated on the label of 1914 and failed to modify this data to represent current modern political boundaries. This error was further carried over into a checklist (Appendix 1 of Whittington 2003) which included an incomplete map. The details are here corrected (Sylhet is in Bangladesh with co-ordinates 24°53'N; 091°52'E) and included in Figure 1 .

Host: unknown.

Remarks: The GNS (2006) catalogue lists two locations for Menglong, both in the mountainous region of south western Yunnan province: 21°36'N; 100°40'E & 23°21'N; 102°20'E; both locations are given on Fig. 1 , distinguished from other locations for this species by arrows.

Agadasys xizangensis , sp.nov.

Type locality: Motuo, Xizang Province China; Holotype in IZCAS

Etymology: originating from Xizang Province.

Diagnosis: Ground colour predominantly grey to dark brown contrasting with pale cream markings on postpronotal lobe, propleuron, on posterior portion of anepisternum and mottled on abdominal tergites; head with obvious brown ovals adjacent to ocellar triangle; setae on R1 as long as the distance across the bases of three setae; sclerotized portion of glans, in male postabdomen, covering less than 50% of apex, lateral lobes weakly defined on side corresponding to basal caecum, appearing as shallow curves; acrophallus sharply curved.

Body length 4.0 mm; wing length 4.8 mm.

Colour/Vestiture: Ground colour predominant grey to dark brown. Contrasting pale cream markings on postpronotal lobe, propleuron, posterior portion of anepisternum, scutellum and on abdominal tergites. Flagellomere 1 completely pale cream. Vertex to parafacials orange, with distinct dark brown ovals adjacent to ocellar triangle (unevenly developed on each side; that on the left being almost twice the area of that on the right, reaching from ocellar triangle to eye margin); gena, antennal groove, palpus, median occipital sclerite and postgena pale cream; face brown. Legs pale cream coloured except for dark brown bands as follows: basally on second and third femora, subapically on all femora; sub-basally and apically on all tarsi; tarsomeres progressively darker orangebrown toward apex. Abdomen with basal portion of tergites 1 and 2 dark brown, tergites 3- 5 mottled dark brown over paler cream coloured patches, progressively darker brown distally. Setulae fair to slightly golden, intermingled on gena, notum and abdominal segments with dark brown setulae. Microtrichia white, widespread, particularly noticeable on pleurites and subscutellum.

Head: Eye elongate and densely setose. Outer ventral setulae on scape long, reaching halfway along flagellomere 1. Arista pubescent. Occiput slightly concave either side of median occipital sclerite. Gena deep, distance from ventral eye-margin to ventral edge of gena (in lateral view) equal to width of flagellomere 1. Postgena angular at ventroposterior edge (approximately right-angled). Setulae brown on ocellar triangle, along dorsal eye margin from ptilinum to vertex and dorsal portion of postgena and palpus; intermingled with weaker white setulae on anterior and lateral margins of ocellar triangle, dorsal and basal parts of palpus, on occiput and ventral portion of postgena. Setae as in generic description; orbitals slightly lateroclinate. Postocular setulae in three rows.

Thorax: Scutellum convex and strongly rounded at margin, apical margin and dorsal midline with shallow depression. Setae as in generic description ( Whittington 2000a). Legs: Setulae moderately dense and long, white, interspersed with black, tending to be more seta-like on ventral surface of fore femur and dorsal surface of tibia. Mid coxal prong pale and narrow. Anterior margin of tarsomeres with short, thick, black pre-apical setae. Wing (Fig 2): Black setae on R1 long, as long as the distance across the bases of three setae. Setae on R4+5 shorter and more widely spaced; only one on the distal discal portion of M.

Abdomen: as in generic description. Male postabdomen ( Fig 3 ): preglans elongate; sclerotized portion of glans covering less than 50% of apex, lateral lobes weakly defined on the basal caecular side, appearing as shallow curves; apex of glans with paired terminal lobes between which rises a stout, unsclerotized, apical vesicle, pointed apically, with the tip curved back; acrophallus sharply curved.

Material examined: Holotype male, China: Xizang Province, Motuo, 1100m, 21.i.1981, Han Yin-Heng (IZCAS). In moderately good condition, lacking the left antenna and left fore leg beyond the coxa. The right wing is folded at the flexion line.

Distribution: Known only from Xizang Province, China. Motuo is a county, not listed in the GNS (2006) catalogue, but the co-ordinates for the location were estimated from Yin (2006) to be approximately 29°19’N 95°18’E. Donoghue et al. (1997) provided background information about the region (see remarks).

Host: unknown

Remarks. The body form (gross morphology) and patterning of this species is similar to that of A. hexablepharis and the abdominal pattern is almost identical (see Whittington 2000a, fig. 8). The new species differs from A. hexablepharis by having predominantly grey ground colour and darker head, scutum, pleura and abdominal tergites; head distinctly orange with brown ovals adjacent to ocellar triangle; postgena angulate; wings with a more restricted radial pattern; setae not so dense and long and, on the abdomen, represented by a greater proportion of black than white setae.

The single type specimen was collected from Motuo Country, which is the only Chinese county (of 2862 county-level (xinj) divisions (Wikipedia 2006)) having no highway traffic; travel is thus difficult and lengthy, requiring three days walk from the nearest road point. Fieldwork is not planned in the area by either author and, considering the high diversity of this ‘hot-spot’ zone, together with impending human impact on the area ( Donoghue et al., 1997), it was therefore considered valuable to publish this single specimen description despite the lack of comparative material. No other specimens have been encountered in Chinese, American or European insect collections.

The local Motuo climatic patterns follow the main ridge of eastern Himalayas, with a subtropical climate prevailing on the southern slope of the mountain range ( Donoghue et al., 1997). This is consistent with the know distribution patterns of Agadasys and, more broadly, of Plastotephritinae. The average annual temperature is about 16°C, and the annual precipitation averages 300 mm (source gives it as 2357 cc (or ml)). The vegetation consists of wet, evergreen, and semi-evergreen broad-leaved forests, with Castanopsis , Lithocarpus , Cyclobalanopsis , Machilus , Cinnamomum , Actinodaphne , Manglietia , Magnolia , Illicium and Alcimandra as the dominant trees. ( Donoghue et al., 1997).

Figures

FIGURE 1. Distribution of Oriental Plastotephritinae. A. hexablepharis Whittington, 2003 (arrows indicate alternate possible locations for Chinese material examined); A. xizangensis sp. nov.; R. latiuscula (Walker, 1856).

FIGURE 3. Apex of male distiphallus; lateral view from left & right hand sides. ap = acrophallus; av = apical vesicle; bc = basal caecum; g = glans; pg = preglans. Bar = 0.5 mm.