Asiorrhina parasiatica, Blagoderov, Vladimir, Hippa, Heikki & Ík, Jan Šev Č, 2009

Blagoderov, Vladimir, Hippa, Heikki & Ík, Jan Šev Č, 2009, Asiorrhina, a new Oriental genus of Lygistorrhinidae (Diptera: Sciaroidea) and its phylogenetic position, Zootaxa 2295, pp. 31-45 : 42

Asiorrhina parasiatica sp. nov.

Material studied. Holotype: Male, Malaysia, Sarawak, Gunung Mulu NP, Alluvial Forest, 23- 29.10.1977, N.M. Collins, Malaise trap; slide mount in Euparal ( BMNHE 819006). Paratype: male, same data as holotype ( BMNHE 819004). Both specimens in BMNH.

Description. Male. Measurements: Head height 0.3 mm; body without head 2.0– 2.3 mm (holotype 2.0); wing, measured from humeral vein, 1.3 mm; antenna 0.8 mm; proboscis 0.54–0.74 mm (holotype 0.54); palpus 0.28 mm.

Head ( Fig. 2 B) rounded, a little higher than wide. Frons bare; vertex and occiput covered uniformly with sparse dark setae. Two ocelli at vertex. Frontal furrow continues on vertex, forming a swelling at site of median ocellus. Eyes dichoptic, reniform, slightly protruding dorsally and with very slight emargination at antennal base. Ommatidia, round, relatively larger than in A. asiatica , 14-15 ommatidia across eye, equal in size, with interocular setae 1.3x ommatidium diameter. Antennae set in middle of head. Scape short, conical, pedicel more or less spherical. Flagellum 14-segmented ( Fig. 3 C). Bases of setae on flagellomeres form round depressions with indistinct folds between them rather than polygons. Flagellomeres 3–14 strongly compressed laterally, with long dorsal setae (length 0.5– 1 x width of flagellomeres) and short setulae anteriorly. Flagellomere 1 length 1.3x width, flagellomere 4 width 0.5x length, apical flagellomere length 2x width, also bearing a small apical articulated appendage ( Fig. 3 E). Clypeus elongated, length ~1.7x width, with two lateral setae at the middle of each side. Length of proboscis approximately 1.8x height of head. Palpi onesegmented, 0.65x length of proboscis, narrow in apical half. Labellum slightly swollen in apical 1/10, pointed apically.

Thorax ( Fig. 4 A). Scutum moderately convex, irregularly setose, with longer setae in anterior part; anterior margin same level as fore coxa. Scutellum with three pairs of setae. Antepronotum not separated clearly from proepisternum, bearing 4 long setae, proepisternum with 9 long setae. Laterotergite medium size, defined, with posteroventral group of 4–5 setae.

Legs. Fore coxae sparsely setose, with 9–10 anterior setae, 6–7 long medio-apical setae and one posteroapical seta. Mid coxae with 8–10 antero-apical and 6–8 latero-apical setae. Hind coxae bare. Tibial organ bordered on proximal side by horseshoe-shaped sclerotized crest ( Fig. 4 C). Mid tibia expanded in apical 1/3, width at apex 2x width at base. Mid tibial spur not equal, external about 2x internal. Hind legs not preserved on both specimens. Claws on fore and mid tarsi pointed.

Wing ( Fig. 5 B). Costal setae long, about 3x width of Costa. R with 15 long setae, other veins bare. Costa reaches wing apex, ends at 5/6th of distance between R5 and M1 apices. R5 straight. M stem reduced, though base of M1 and M2 fork conspicuous. M1 strongly curved back, so reaches wing margin well posteriorly of wing apex. M3+4 sinusoid apically; CuA moderately curved posteriorly. Distance between apices of M2 and M3+4 1.7x distance between M3+4 and CuA. Vein iCu apparent, as strong as CuA. A1 reaches only half of CuA length.

Abdomen. Tergite 8 not preserved. Tergite 9 shorter and more rounded than in A. asiatica , slightly shorter than gonocoxites, with long setae mainly in apical part but without apical spicules ( Fig. 7 A). Gonocoxites slightly tapering towards apex ventrally, less densely setose than in A. asiatica . ( Fig 7 B). Gonostylus shorter than gonocoxite, with two blunt, apical lobe-like teeth of equal length and a thin, long medial flagellate seta slightly distad of the middle of mesial margin ( Fig. 7 C).

Etymology. The specific name refers to its similarity to A. asiatica

Differential diagnosis. A. parasiatica is distinguished from A. asiatica by the following characters: 1) smaller, wing length 1.3 mm (compared to 1.5–1.7 mm); 2) two ocelli (not 3); 3) antennal flagellum strongly laterally compressed (rather than subcylindrical); 4) vein M1 is complete (not basally reduced); 5) tibial organ proximally bordered by a horse-shoe shaped margin (not unbordered); and 6), male tergite 9 broader and its setosity is rather uniform (the apical setae not being shorter and stronger).

Figures

FIGURE 2. Male head, frontal view. A: Asiorrhina asiatica (Senior-White), comb. n.; B: Asiorrhina parasiatica, sp. n. (holotype).

FIGURE 3. Antenna (C), antennal flagellomere 4 (A, D) and antennal flagellomere 14 (B, E), lateral view. A, B. Asiorrhina asiatica (Senior-White). C – E. A. parasiatica sp. n., (holotype); scale 0.1 mm.

FIGURE 4. Thorax, lateral view, (A) and tibial organ (B, C) of Asiorrhina. A, C: Asiorrhina parasiatica, sp. n. (holotype); B: Asiorrhina asiatica (Senior-White), comb. n.

FIGURE 5. Wings, dorsal view. A: Asiorrhina asiatica (Senior-White), comb. n.; B: Asiorrhina parasiatica, sp. n.; scale 0.5 mm.

FIGURE 7. Asiorrhina parasiatica, sp. n. (paratype). A: Hypopygium, dorsal view; B: Hypopygium, ventral view; C: Gonostylus, ventral view; scale 0.05 mm.