Pseudacteon setipalpatus Disney et Michailovskaya

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 : 210-213

5. Pseudacteon setipalpatus Disney et Michailovskaya

( Figs. 6A–F ; 7A–F , 24G–H )

Pseudacteon setipalpatus Disney et Michailovskaya, 2000: 39 .

Diagnosis. Female. Apical seta longer than maximum width of palpus; fore tarsomere 5 longer than tarsomere 1; setal palisade 3/4 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 with 2–3 long and 1–2 shorter setulae at rear margin; sternite VI reduced to a narrow transverse strip, with 3 long setae each side; dorsum of oviscape with 11–12 minute setulae.

Female. Frons ( Fig. 6A ) brown, with 16–22 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 about straight, upper interfrontal setae further apart than either is from an upper fronto-orbital seta. Flagellomere 1 brown and subglobose. Palpus pale brown, with 5 long setae, apical one longer than maximum width of palpus. Labrum and labella pale yellow.

Thorax brown. Scutellum with two pairs of setae, posterior four times length of anterior. Legs brown, fore leg being lighter. Ratios of lengths of fore tarsomeres about 0.98: 0.77: 0.70: 0.59: 1, with all five bearing a posterodorsal seta palisade ( Fig. 6C ). Setal palisade terminates 3/4 (0.75) along tibia ( Fig. 6D ). Setae below basal half of hind femur a little shorter than those of anteroventral row of outer half ( Fig. 6E ). Wing ( Fig. 6B ) length 1.05–1.10 mm, width 0.52–0.54 mm, width/length 0.49. Costal index 0.43–0.44. Costal ratios 1.22:1. Costal cilia 0.070 mm long. Costa with 12 dorsal setulae. Alula with 2 setae. Veins brown, membrane brownish gray. Haltere brown.

Abdominal tergites brown and tergites 1–5 with sparse minute setulae on posterior margins. Tergite VI ( Fig. 24G ) reduced to a narrow anterior strip in middle but each lateral quarter bears 2–3 long and 1–2 short setulae at rear margin. Venter brown. Sternite VI ( Figs. 6F , 24H ) reduced to a narrow transverse strip, with 3 long setae each side. Oviscape brown. The dorsum of the oviscape with about 11–12 minute setulae ( Fig. 6F ).

Male. Frons ( Fig. 7A ) yellowish brown, with about 14–16 setulae. Lower pairs of supra-antennal setae a litter lower than lower fronto-orbital setae, upper pair higher than lower front-orbital setae. Second row of frontal setae clearly concave, upper interfrontal setae further from each other than either is from an upper fronto-orbital seta. Flagellomere 1 brown, subglobose. Palpus pale yellow, with 4 very long setae, apical one 1.5 times longer than maximum width of palpus.

Thorax brown. Scutellum with a pair of setae, posterior twice length of anterior. Legs yellowish brown. Ratios of lengths fore tarsomeres 1: 0.70: 0.70: 0.63: 1, with all five bearing a setal palisade ( Fig. 7C ). Setal palisade extends 2/3 (0.68) length along mid tibia and comprising 28 modified setulae ( Fig. 7D ). Setulae below basal half of hind femur clearly shorter and weaker than those of anteroventral row of outer half ( Fig. 7E ). Wing ( Fig. 7B ) length 1.16 mm, width 0.57–0.58mm, length/width 2.00. Costal index 0.45. Costal ratio 1.1: 1. Costal cilia 0.065 mm. Alula with 2 setae. Haltere brown.

Abdomen. Tergites brown with minute sparse setulae. Venter brown. Male terminalia brown and anal tube pale yellow ( Fig. 7F ).

Distribution. China (Liaoning, Jilin), Russia.

Specimens examined. 1♀, Liaoning, Benxi, Mt. Wunv (41°19′58.76″N, 125°25′11.81″E), 19-Sep-2010, Lina Huang ; 1♀, Jilin, Tonghua, Jian (41°16′26.57″N, 126°07′03.25″E, 738 m), 23-7-2014, Jiangfeng Wang ; 1♂ (slide), Jilin, Baishan, Fusong (42°02′38.74″N, 127°47′31.17″E, 1033 m), 27-Jul-2014, Jianfeng Wang ; 3♀ 11♂, Jilin, Baishan, Fusong (42°02′38.74″N, 127°47′31.17″E, 1033 m), 27-Jul-2014, Jianfeng Wang ; 2♀ (slide), Jilin, Baishan, Changbai county (41°34′03.02″N, 128°17′53.14″E, 1002 m), 29-Jul-2014, Jianfeng Wang ; 5♂, Jilin, Yanbian, Tuan (42°11′17.38″N, 128°10′24.65″E; 1120m), 31-July-2014, Jianfeng Wang ; 1♀ 1♂ (slides), Jilin, Yanbian, Tuan , (42°11′17.38″N, 128°10′24.65″E; 1120m), 31-July-2014, Jianfeng Wang ; 1♀ (slide), Jilin, Yanbian, Wangqing (43°15′26.19″N, 129°55′35.23″E, 550 m), 8-Aug-2014, Jianfeng Wang ; 1♀ 2♂, Jilin, Yanbian, Wangqing (43°10′01.32″N, 129°38′03.18″E; 392 m), 9-Aug-2014, Jianfeng Wang .

Remarks. This species is similar to P. inticlinatus sp. nov. It differs from the latter by the apical seta longer than the maximum width of palpus, and abdomina sternite VI with 2 long setae each side. The male of the species is similar to that of P. trapeziformis Zhang et Liu, 2019 , it differs from the latter by apical seta more than two times of the maximum width of palpus and fore tarsomere 5 as long as tarsomere 1.

Figures

FIGURES 6A–F. Pseudacteon setipalpatus Disney et Michailovskaya, 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, ventral view. Scale bar = 0.1mm.

FIGURES 7A–F. Pseudacteon setipalpatus Disney et Michailovskaya, male. A. head, anterior view; B. wing, dorsal view; C. fore tarsus, posterior view; D. mid tibia, posterior view; E. hind femur, anterior view; F. male terminalia, left view. Scale bar = 0.1mm.

FIGURES 24A–J. Tergite VI and sternite VI of females.A–B. P. quadrisetalis Liu et Cai; C–D. P. trapeziformis Zhang et Liu; E–F. P. inticlinatus sp. nov.; G–H. P. setipalpatus Disney et Michailovskaya; I–J. P. reticulatus sp. nov. Scale bar = 0.1mm.