Postoptica continentalis Lengyel & Papp, 2012

Lengyel, Gábor Dániel & Papp, László, 2012, Two New Peculiar Phoridae (Diptera: Aschiza) From Vietnam, Raffles Bulletin of Zoology 60 (1), pp. 129-136 : 131-134

Postoptica continentalis Lengyel & Papp , new species

( Figs. 1 , 9–12a–f )

Material examined. — Holotype. Male , VIETNAM: Hoa Binh Province 6 km W of Tan Son, forest edge in a gorge, sweeping, 938 m, 20.7417977°N, 104.9401984°E, VN2010 PL _25, coll. Papp, L., Peregovits, L., Soltész, Z., & Lengyel, G., 22 Apr.2010.

Paratype. — 1 male Vietnam, Bac Kan, Ba Be National Park , forest in the gorge behind the headquarter, 200 m, 22.417137°N, 105.632505°E, sweeping, coll. Papp, L., Peregovits, L., Soltész, Z., & Lengyel, G., 17–18 Apr.2010 .

Diagnosis. — Postoptica continentalis new species characterised by its genitalic difference.

Description. — Male. Body length: 4.8 mm. Head dark brown. Eyes almost touching each other behind the ocellar triangle. Third antennal segment with numerous long setae ( Fig. 9 ). Largest pair approximately as long as the diameter of third segment. Arista apical, covered with similar microtrichia as the surface of third segment. Palpus with six strong setae emerging on the distal ventral margin, and many smaller setulae on the inner surface (Fig. 10). Stem of palpus quite long.

Thorax dark brown. Scutellum with two weak lateral setae. Anepisternum with eight or nine setulae in a cluster at the distal middle part, and seven in the upper portion.

Legs without differentiated setae or palisade of setulae. Fore coxa, femur, tibia and metatarsus with relatively deep and long grooves. Fore tibia strongly, mid tibia slightly, hind tibia a little bit harder widening distally. Claws strong.

Wings (Fig. 11) clear, with very reduced wing venation. Only the costa and R 4+5 well developed, other veins weak, hardly discernible. Axillary ridge with 12 setae, (10 in P. platypezoidea ). Haltera brown, knob of haltera relatively large.

Abdominal tergites dark brown. Epandrium and hypandrium fused along a longer section ( Fig. 12a–b ); epandrium bare, hypandrium with microtrichia ( Fig. 12a ). Cerci in a semicircular orifice of epandrium ( Fig. 12a, d ), cerci with short setae. Caudal to cerci there are two intricate processes, the left surstylus and the surstylar process (signed as “s” and “p” on Fig. 12c ). Surstylus with a black long thorny peg (i.e. not a thorn) and with a digitiform smaller process ( Fig. 12d ). Numerous but not long setae emerge on it. Surstylar process quite robust, its apex seems sharp in left lateral view, actually not sharp apically (see Fig. 12a ). Cavity of hypandrium with a sack, whose wall is covered by curved short thornlets ( Fig. 12e–f ). Phallic organ of an intricate structure: a medial well-sclerotised ring, an inner laterally directed subapical process, and an apical “brush” of dark but less sclerotised acrophallus ( Fig. 12d ) present.

Fig. 4. Left antenna Abaristophora hirticornis new species from lateral view. Scale bar = 0.1 mm. Fig. 5. Metathorax of Abaristophora hirticornis new species from lateral view.

Fig. 6. Fore tarsomeres of Abaristophora hirticornis new species. Scale bar = 0.1 mm.

Fig. 7. Wing of Abaristophora hirticornis new species. Scale bar = 0.1 mm.

Etymology. — The name ‘ continentalis ’ refers to the species having been found in continental Asia.

Distribution. — At present known only from Vietnam.

Affinities. — P. continentalis new species bears close resemblance to P. platypezoidea . These two species could be certainly distinguished by the structure of the male genitalia ( Fig. 12 a–f ). The holotype of P. platypezoidea is slidemounted, therefore it can only be examined in one plane, and this limited the information that could be extracted from the specimen. Brown (1994) provided additional figures of the genitalia for this species. Based on his figures, it appears that the surstylus in case of P. platypezoidea is more pointed, short and wide, while in P. continentalis it is long, narrower with rounded tip. Additional specimens may help identify more distinctions between these two species.

Figures

Fig. 1. Postoptica continetalis new species male habitus. Scale bar = 1 mm.

Fig. 9. Right antenna of Postoptica continetalis new species from lateral view. Scale bar = 0.1 mm.

Fig. 12. Postoptica continentalis new species, paratype, male genitalia: a, genitalia in the view of Disney’s (1987) Fig.(4); b, right lateral view; c, left lateral view; d, subventral view; e, hypandrium with the thorny sack inside, as if hypandrium would be transparent; f, thorns in higher magnification. Scale bars = 0.2 mm (a–e), 0.1 mm for (f). Abbreviations: e – epandrium; h – hypandrium; s – surstylus; p – surstylar process; a – adeagus.