Xenokeroplatus continentalis L. PAPP, 2006

Papp, L., Merz, B. & Földvári, M., 2006, DIPTERA OF THAILAND A summary of the families and genera with references to the species representations, Acta Zoologica Academiae Scientiarum Hungaricae 52 (2), No. 2, pp. 97-269 : 137-139

Xenokeroplatus continentalis L. PAPP , sp. n.

( Figs 34–37 )

Holotype male ( HNHM, flagellomeres 8-lost, right wing preserved between two pieces of cover glass glued under the specimen, abdomen with genitalia in a plastic microvial with glycerol): THAILAND: Doi Suthep N. P., along a forest brook, Oct 31, 2004, No. 11, leg. L. PAPP & M. FÖLDVÁRI.

Paratype female: same data as for the holotype.

Measurements in mm: body length: 4.62 (holotype), 1.27 (head+thorax) 3.64 (abdomen), total body 4.86 (paratype), wing length 3.12 (holotype), 3.88 (paratype), wing breadth 0.96 (holotype), 1.16 (paratype).

Head, scutum, scutellum, metanotum and abdomen blackish brown.

Occiput much bulging, ocellar triangle positioned anterior to middle of head. Two lateral large ocelli only. Antenna black. First flagellomere much longer than broad, flagellomeres 2 quadratic in profile (female) or broader than long (male), flagellomeres 3 to 13 broader than long, apical flagellomere rounded apically, length/width 7/5, i.e. 0.075 / 0.053 mm. Eyes covered by dense cilia. Proboscis minute, palpi 2-segmented, apical segment oval. Frontal tubercle very small triangular, not protruding from plane of frons. Sides of frons (“orbitalia”) and vertical eye margin with rather long proclinate setae.

Scutellum triangular (0.29 mm broad, 0.185 mm long, holotype), without any setae. Metanotum strongly conical. Pleura, coxae and legs mainly dirty yellow. Prosternum short but very broad, bare. Anepisternum and laterotergite bare, latter may be brown fumose.

Fore and mid coxae with numerous short black setae, hind coxa with a row of 5–6 setae on posterior lateral edge. Tibiae and metatarsi (basitarsi) extremely long, microchaetae on tibiae ordered in rows in their whole length. Length of tibiae and basitarsi: t1 0.815, mt1 2.85 mm, ratio 3.49; t2 1.36, mt2 2.67 mm, ratio 1.97. Tibial spurs 1: 0: 1 (!), medial spur on hind tibia minute but discernible. Tibial apical combs on t1 (short, medial), t2 (short medial), t3 (lateral, rather short). No macrochaetae on legs. Claws almost straight, ventral dentation very fine, no pulvilli.

Wing light brown with diffuse darker brown apex and ventral part back to cubital veins. Veins darker brown. Costa continued to 3/5 of R5-M1 costal section.Vein R1 setose dorsally, R5 setose only in apical 1/3, proximally to R4. Vein Sc1 short thin, apex just overrun R-M crossvein. No sign of 34–35, 0.2 mm for Fig. 36 , 0.1 mm for Fig. 37

Sc2. R4 minute, shorter than 0.05 mm. Veins M 1 and M2 convergent. Cu 1 slightly curved, strong, continued to wing margin. Cu 2 does not reach visible part of M2. A1 straight, runs close to Cu 2 and not reaching Cu-M. Costal ratios (holotype): 90:51:31, i.e. 0.98: 0.55: 0.34 mm. M1–2 stalk and basal part of M1 and M2 missing, visible parts 1.20 mm and 1.62 mm. Calypter anterobasally with a small pit with minute black setulae. Halteres all dark .

Abdomen very narrow, only 0. 34 mm at thickerst, slightly higher than broad. Sternites yellowish broad, laterally meet tergites.

Male tergite 9 ( Figs 34–35 ) extremely large, ventral cranial edges almost meet sagittally, connection of genitalia to abdomen rather narrow, only 0.12 mm of that large fly. Tergite 9 with slightly convex caudal end. Hypoproct with some thick black setae. Sternite 9 was not detected. Cerci rather small. Gonocoxites short, i.e. rather small, without ventral incision but with a sagittal plate, which is 2/3 as long as ventral length. Gonocoxites with a basally inserted process ( Fig. 37 ), or, a pair of processes, which fused sagittally to each other, and bears similarly thick black thorns like gonostylus. Gonostylus ( Figs 36–37 ) very long, apex narrowly rounded in lateral view. All medial surface of gonostylus with thick, more or less blunt black thorns, as in its congeners. In addition, gonostyli on medial edge with medially directed processes, which bears 2 pairs of black thorns ( Fig. 37 ).

Female cerci broad at base, almost sharply pointed at apex, with medium long and not thick setae only.

X. continentalis sp. n. keys out to X. riparius MATILE (Solomon Is.) but gonostylus is even longer and gonocoxal medial process must be different (cf. fig. 988 of MATILE 1990). This is the first known species of Xenokeroplatus from the Asian continent.

Figures

Figs 34–37. Xenokeroplatus continentalis sp. n., holotype male.34 = outer genitalia, dorsal view, 35 = same, ventral view, 36 = contour of gonostylus, lateral view, 37 = apical part of gonocoxites with medial process and basal half of gonostyli, dorsal view, tergite 9 removed. Scales: 0.4 mm for Figs