Pseudacteon hexasetalis Liu et Wang

Liu, Guang-Chun & Disney, R. Henry L., 2022, Revision of the ant-parasitizing genus Pseudacteon Coquillett (Diptera, Phoridae) from China, Zootaxa 5138 (3), pp. 201-237 : 230-231

17. Pseudacteon hexasetalis Liu et Wang

( Figs. 21A–F , 26E–F )

Pseudacteon hexasetalis Liu et Wang, 2013: 56 .

Diagnosis. Female. Frons with 3 pairs of supra-antennal setae; apical seta longer than maximum width of palpus; tarsomere 5 shorter than tarsomere 1; setal palisade 2/3 length of mid tibia; setulae below basal half of hind femur shorter than those of anteroventral row of outer half; tergite VI with 3–4 short setulae on each side; sternite VI divided into two oval pieces, with some weak setulae; dorsum of oviscape each side with 5 with short setulae apically and 5 setulae basally; venter of oviscape arrow-shaped, with 2 minute setulae.

Female. Head. Frons ( Fig. 21A ) yellowish brown, with 26 frontal setulae. Frons with 3 pairs of supra-antennal setae, lower pair is proclinate, middle and upper ones reclinate; upper pair higher than lower fronto-orbital setae. Flagellomere 1 pear-shaped and arista brown. Palpus pale yellow, with long setae, apical one longer than maximum width of palpus. Labrium and labella pale yellow.

Thorax. Brown. Scutellum with two pairs of setae, posterior twice length of anterior. Legs yellow. Ratios of lengths of fore tarsomeres about 1.05: 1.01: 0.86: 0.85: 1, with all five bearing a postero-dorsal seta palisade ( Fig. 21C ). Setal palisade extends 2/3 length of mid tibia and comprising 19 modified setulae ( Fig. 21D ). Setae below basal half of hind femur a little shorter than those of anteroventral row of outer half ( Fig. 21E ). Wing ( Fig. 21B ) length 0.91–1.02 mm, width 0.41–0.42, width/length 0.41–0.45. Costal index 0.35–0.36. Costal ratio 1.44: 1. Costal cilia 0.05 mm. Alula with 2 setae. Haltere brown.

Abdomen. Tergites brown with minute sparse setulae only. Tergites II–V all very much broader than long, but progressively narrowing from tergite II backwards. Tergite VI with 3–4 short setulae on each side ( Fig. 26E ). Venter grayish brown and segments 1–5 bare. Sternite VI dark brown, with some weak setulae ( Fig. 26F ). Oviscape yellowish brown. The dorsum of the oviscape each side with 5 short setulae apically and 5 setulae basally. The venter of the oviscape arrow-shaped, with 2 minute setulae ( Fig. 21F ).

Male. Unknown.

Distribution. China (Guangxi).

Specimen examined: 1♀ (holotype), Guangxi, Shanglin, Mt. Daming (23°16′48″N, 108°15′36.00″E; 800m), 10-Aug-2011, Dianxing Feng and Jianfeng Wang .

Remarks. The new species is easily distinguished from other species of the genus in having three pairs of supra-antennal setae and by the characters of oviscape.

Figures

FIGURES 21A–F. Pseudacteon hexasetalis Liu et Wang, female. A. head, anterior view; B. wing, dorsal view; C. fore tarsus, posterior view; D. mid tibia, posterior view; E. hind femur, anterior view; F. ovipositor, dorsal view. Scale bar = 0.1mm.

FIGURES 26A–J. Tergite VI and sternite VI of females.A–B. P. yunnanensis sp. nov.; C–D. P. calceoliformis sp. nov.; E–F. P. hexasetalis Liu et Wang; G–H. P. tianmuensis sp. nov.; I–J. P. parviflavus sp. nov. Scale bar = 0.1mm.