Pseudacteon parviflavus, Liu & Disney, 2022

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 : 232-237

19. Pseudacteon parviflavus sp. nov.

( Figs. 23A–F , 26I–J )

Diagnosis. Female. Apical seta longer than maximum width of palpus; tarsomere 5 a little longer 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 reduced to a narrow anterior strip in middle but each lateral quarter bears 2 long and 2 short setulae at rear margin; sternite VI reduced to a anterior strip in middle, and enlarging in both sides, bearing 2 long and 2 short setulae; dorsum of oviscape with about 4–5 minute setulae each side.

Female. Frons ( Fig. 23A ) yellow, with 10–12 setulae. Supra-antennal setae as strong as adjacent frontal setae, upper pair being higher on frons than lower fronto-orbital setae. Lower interfrontal seta directly under lower frontoorbital seta. Second row of frontal setae slightly concave, upper interfrontal setae further apart than either is from an upper fronto-orbital seta. Flagellomere 1 brownish yellow and subglobose. Palpus pale yellow, with 4 long setae, apical one longer than maximum width of palpus. Labrum and labella yellow.

Thorax brown. Scutellum with two pairs of setae, posterior twice length of anterior. Legs yellow. Ratios of lengths of fore tarsomeres about 0.97: 0.79: 0.71: 0.69: 1, with all five bearing a postero-dorsal setal palisade ( Fig. 23C ). Setal palisade terminates 2/3 (0.63) along mid tibia ( Fig. 23D ). Setae below basal half of hind femur a little shorter than those of anteroventral row of outer half ( Fig. 23E ). Wing ( Fig. 23B ) length 0.82 mm, width 0.41 mm, width/length 0.50. Costal index 0.36–0.38. Costal ratios 1.19:1. Costal cilia 0.033–0.034 mm long. Costa with 9–10 dorsal setulae. Alula with 2 setae. Veins brown, membrane brownish gray. Haltere pale yellow.

Abdominal tergites yellow and tergites I–V with sparse minute setulae on posterior margins. Tergite VI ( Fig. 26I ) reduced to a narrow anterior strip in middle but each lateral quarter bears 2 long and 2 short setulae at rear margin. Venter brown. Sternite VI ( Fig. 26J ) reduced to an anterior strip in middle, and enlarging on both sides, each bearing 1–2 long and 2–3 short setulae. Oviscape yellowish brown. The dorsum of the oviscape with about 4–5 minute setulae each side ( Fig. 23F ).

Male. Unknown.

Distribution. China (Guangxi).

Etymology. The species epithet refers to characters of yellowish body color and small size.

Specimens examined. Holotype. ♀, China: Guangxi, Shangsi, Shiwandashan, 18-Aug-2011, Jianfeng Wang ; Paratypes. 3♀, same data as for holotype .

Remarks. The new species is a little similar to P. tianmuensis sp. nov. It differs from the latter by longer setal palisade of mid tibia, shorter setulae of sternite VI and yellowish body colour.

Figures

FIGURES 23A–F. Pseudacteon parviflavus sp. nov., 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.