Xenasteia chinensis, Papp, 2005

Papp, L., 2005, Some Acalyptrate Flies (Diptera) From Taiwan, Acta Zoologica Academiae Scientiarum Hungaricae 51 (3), pp. 187-213 : 206-208

Xenasteia chinensis sp. n.

( Figs 18–20 )

Holotype male ( HNHM): Pingtung Hsien, Kenting, Heng-Chun Tropical Botanical Garden, light traps, October 4–6, leg. L. PEREGOVITS & L. PAPP, No. 15. Abdomen with genitalia are prepared and preserved in glycerol in a plastic microvial; its wings are prepared on a normal slide; head and thorax with legs (left hind leg lost) are in canada balsam between two small pieces of cover glass attached to a card.

Description – Measurements in mm: body length ca 1.20 (abdomen downcurved), wing length 1.52, wing breadth 0.59. Frons and thorax darker brown, shiny (frons anteriorly reddish), abdomen blackish brown, shiny.

Head very broad: 0.68 mm. Scape and pedicel reddish yellow, first flagellomere greyish with long fine cilia ( Fig. 18 ). Anterior orbital seta inclinate; 2 posterior orbital pairs present: a short, more medial, proclinate and a long lateral reclinate pair ( Fig. 18 ).

Mesonotum semiglobular, much bulging. One small anterior, plus 1 very large posterior pairs of dorsocentrals, no enlarged prescutellar, 1 katepisternal pairs. Mesonotal chaetae medium long: 1 postpronotal, 1 notopleural, 1 presutural, 1 supra-alar, 1 + 1 postalar (supra-alar and intra-alar) pairs.

Wings hyaline, shiny, veins pale yellow. Vein R 4+5 gently downcurved in its distal half (but less so than in HARDY’ s two species figured). Subcostal setae on costa 0.11 and 0.10 mm. Costal index 1.33, i.e. closer to that of X. sabroskyi and much less than to that of X. okinawensis . Medial vein continued to 3/7 of wing. Longest ventral fringe 0.055 mm. Alula blackish with 10 long (up to 0.09

Legs all yellow. No characteristic setae on legs (except for the mid ventroapical, 0.09 mm), but with long dense microchaetae. Claws long, evenly curved.

Abdomen short and comparatively broad. Epandrium’s dorsal “bridge” linear ( Fig. 19 ), hypandrium robust with a pair of large caudally directed processes, each bearing 2 medium-long thick setae ( Figs 19–20 ). Cerci large with dorsally curved long strong setae. Surstylus ( Fig. 19 ) perpendicularly curved, caudally directed part broadest at apical 2/5, apex blunt. Ejaculatory apodeme distinct though bacilliform. Aedeagal apodeme medium long.

Remarks – Xenasteia chinensis sp. n. runs to X. palauensis HARDY, 1980 in HARDY’ s key but knob of halteres black (yellow in palauensis ). Male genitalia are massively different (cf. figs 4a, b of HARDY 1980).

Figures

Figs 18–20. Xenasteia chinensis sp. n., holotype male. 18 = head, dorsal view; 19–20 = genitalia: 19 =lateral view, 20 =caudal-subventral view.Scale bars:0.4 mm for Fig.18, 0.1 mm for Figs 19–20 mm) setae. Halter with longish, not globular black knob, yellow stalk.