Pseudacteon pullum Michailovskaya, 1995

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 : 220-222

11. Pseudacteon pullum Michailovskaya

( Figs. 14A–F , 15A–F , 25C–D )

Pseudacteon pullum Michailovskaya, 1995: 2 (♂).

Diagnosis. Female. Frons ( Fig. 16A ) brown, with 24–26 setulae; apical seta of palpus longer than maximum width of palpus; fore tarsomere 5 longer than tarsomere 1; setal palisade extends more than 1/2 (0.60) length of mid tibia; tergite VI triangular, each side with 2 long and 4–5 short setulae; sternite VI divided into two irregular formed pieces, each with 2 long and 2–3 short setulae. Male. Setal palisade extends to or less than 1/2 (0.60) length of mid tibia.

Female. Body length 1.24 mm. Frons ( Fig. 14A ) brown, with 24–26 setulae. Supra-antennal setae as strong as adjacent frontal setae, lower pair being closer together and as high as lower fronto-orbital setae. Lower interfrontal seta near eye margin, but not directly under lower fronto-orbital seta. Lower fronto-orbital setae even nearer eye margin and lower on frons than upper supra-antennal setae. Second row of frontal setae a little concave, with upper interfrontal setae clearly further apart than either is from an upper fronto-orbital seta. Flagellomere 1 brown and subglobose. Palpus pale brown, with long setae, apical one longer than maximum width of palpus. Labrum and labella pale yellow.

Thorax brown. Scutellum with two pairs of setae, posterior twice length of anterior. Legs yellowish brown to brown, hind femora being darkest. Ratios of lengths of fore tarsomeres about 0.79: 0.67: 0.62: 0.61: 1, with all five bearing a setal palisade ( Fig. 14C ). Setal palisade extends more than 1/2 (0.60) length of mid tibia ( Fig. 14D ). Setulae below basal half of hind femur shorter and weaker than those of anteroventral row of outer half ( Fig. 14E ). Wing ( Fig. 14B ) length 1.06–1.08 mm, width 0.56 mm, width/length 0.52. Costal index 0.38. Costal ratios 1.40:1. Costal cilia 0.05 mm long. Costa with 12–14 dorsal setulae. Alula with 2 setae. Veins brown, thin veins being paler. Membrane brownish gray. Haltere pale yellow.

Abdominal tergites brown and tergites 1–5 with sparse minute setulae only. Tergite VI ( Fig. 25C ) about triangular, each side with 2 long and 4–5 short setulae. Sternite VI ( Fig. 25D ) divided into two irregular pieces, each with 2 long and 2–3 short setulae. Oviscape arched. The dorsum of the oviscape with about 10 small setulae each side, three of those near apex are a little longer ( Fig.14F ).

Male. Frons (fig. 15A) brown, with 20–22 setulae. Supra-antennal setae as strong as adjacent frontal setae, lower pair being closer together and as high as lower interfrontal setae. The latter near eye margin, almost directly under lower fronto-orbital setae. Lower fronto-orbital setae even nearer eye margin and clearly lower on frons than upper supra-antennal setae. Second row of frontal setae a little concave, with upper interfrontal setae further apart than either is from an upper fronto-orbital seta. Flagellomere 1 brown and subglobose. Palpus pale brown, with long setae, apical one longer than maximum width of palpus. Labrum and labella whitish yellow.

Thorax brown. Scutellum with two pairs of setae, posterior twice length of anterior. Legs yellowish brown to brown, hind femora being darkest. Ratios of lengths of fore tarsomeres about 0.98: 0.66: 0.66: 0.59: 1, with all five bearing a setal palisade ( Fig. 15C ). Setal palisade extends to or less than 1/2 (0.60) length of mid tibia ( Fig. 15D ). Setulae below basal half of hind femur shorter and weaker than anteroventral setulae of outer half ( Fig. 15E ). Wing ( Fig. 15B ) length 0.81–0.82 mm, width 0.39 mm, width/length 0.48. Costal index 0.39–0.40. Costal ratios 1.36–1.37: 1. Costal cilia 0.055–0.056 mm long. Costa with 10–12 dorsal setulae. Alula with 2 setae. Veins brown, thin veins being paler. Membrane brownish gray. Haltere pale yellow.

Abdominal tergites brown, with sparse setulae at rear. Male terminalia brown and anal tube whitish yellow. Left side of epandrium with 5–6 long setulae ( Fig.15F ).

Distribution. China (Jilin, Liaoning), Russia.

Specimens examined. 1♀ 1♂, Jilin, Yanbian, Wangqing (43°15′26.19″N, 129°55′35.23″E, 380 m), 7-Jul-2014, Jianfeng Wang ; 7♂, Jilin, Tonghua, Jian (41°16′26.57″N, 126°07′03.25″E, 738 m), 23-Jul-2014, Jiangfeng Wang ; 8♂, Jilin, Baishan, Fusong (42°02′38.74″N, 127°47′31.17″E, 1033 m), 27-Jul-2014, Jianfeng Wang ; 1♀ 1♂ (slides), Jilin, Tonghua, Jian (41°16′26.57″N, 126°07′03.25″E, 738 m), 22-Jul-2014, Jiangfeng Wang ; 5♂, Jilin, Tonghua, Jian (41°16′26.57″N, 126°07′03.25″E, 738 m), 23-Jul-2014, Jiangfeng Wang ; 1♂, Liaoning, Benxi, Mt. Wunv (41°19′58.76″N, 125°25′11.81″E), 8-Jul-2014, Meng Yang ; 10♂, Liaoning, Shenyang, Dongling (41°50′52.58″N, 123°35′42.46″E), 27-Jun-2012, Guangchun Liu ; 16♂, Liaoning, Benxi , Benxi County (41°12′46.92″N,124°40′18.5 2″E), 22-Jun-2016, Jie Han ; 13♂, Liaoning, Dandong, Mt. Baishilazi (41°6′32.49″N, 123°1′37.41″E), 22-Jun-2021, Jianfeng Wang ; 1♀ 1♂, Liaoning, Tieling, Mt.Longshou (42°17′38.48″N, 123°51′46.87″E), 23-Jun-2019, Jiao Zhang ; 1♀ 2♂ (slides), Liaoning, Dandong, Fengcheng, Mt. Fenghuang (40°25′48.28″N, 124°5′33.99″E), 14-Sep-2010, Jianfeng Wang ; 6♀, Liaoning, Dandong, Fengcheng, Mt. Fenghuang (40°25′48.28″N, 124°5′33.99″E), 14-Sep-2010, Jianfeng Wang ; 1♀ (slides), Liaoning, Dandong, Fengcheng, Mt. Fenghuang (40°25′48.28″N, 124°5′33.99″E), 14- Sep-2010, Jianfeng Wang ; 4♂, Liaoning, Shenyang, Dongling (41°50′52.58″N, 123°35′42.46″E), 2-May-2014, Jianfeng Wang ; 1♂ (slide), Liaoning, Shenyang, Dongling (41°50′52.58″N, 123°35′42.46″E), 2-May-2014, Jianfeng Wang ; 6♂, Liaoning, Anshan, Mt. Qianshan (41°0′20.08″N, 123°6′57.81″E), 16-Aug-2018, Jiao Zhang ; 1♂ (slide), Liaoning, Jinzhou, Beizhen, Mt. Yiwulv (41°36′30.72″N, 121°43′7.65″E), 4-Jul-2018, Jiao Zhang .

Remarks. This species is originally described from the male sex. The males of this species are variable, especially, the number of modified setulae in the setal palisade of mid tibia, which range from 4–18 setulae ( Disney & Michailovskaya 2000). It is easily confused with the male of P. formicarum ( Verrall, 1877) . The female of the species looks similar to the female of P. boltupalpatus Michailovskaya, 2000 , it differs from the latter by wider of abdominal tergite VI, irregular sternite VI, larger width/length ratio of wing and larger vein costal ratio.

Figures

FIGURES 14A–F. Pseudacteon pullum 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 15A–F. Pseudacteon pullum Disney et Michailovskaya, male. A. head, anterior view; B. wing, dorsal view; C. fore tarsus, anterior view; D. mid tibia, posterior view; E. hind femur, anterior view; F. terminalia, left view. Scale bar = 0.1mm.

FIGURES 16A–F. Pseudacteon obtusatus Liu et Cai, female.A. head, anterior view; B. wing, dorsal view; C. fore tarsus, anterior view; D. mid tibia, posterior view; E. hind femur, anterior view; F. ovipositor, ventral view. Scale bar = 0.1mm.

FIGURES 25A–J. Tergite VI and sternite VI of females. A–B. P. rudisetosus Disney et Michailovskaya; C–D. P. pullum Michailovskaya; E–F. P. obtusatus Liu et Cai; G–H. P. linzhiensis sp. nov.; I–J. P. shennongjianus sp. nov. Scale bar = 0.1mm.