Phyllomya sichuana Shima & Zhang, 2022

Shima, Hiroshi, Zhang, Wenxia & Tachi, Takuji, 2022, A systematic study of Old World Phyllomya Robineau-Desvoidy (Diptera: Tachinidae), Zootaxa 5099 (4), pp. 401-449 : 436-440

Phyllomya sichuana Shima & Zhang , sp. nov.

( Figs 1–2 , 87–90 , 98 , 121–122, 126 , 151–152 )

Diagnosis. Head dichoptic; no proclinate orbital setae in male, 2 in female; lower portion of fronto-orbital plate with 1–2 rows of rather sparse, fine, short, white hairs descending to upper 3/4 of parafacial; arista short plumose; thoracic pleura with whitish hairs; 1 presutural and 1 postsutural acrostichal setae; 2 presutural and 3 postsutural dorsocentral setae; 2 katepisternal setae; mid tibia with 1 anterodorsal seta; hind tibia with 3 preapical dorsal setae; male claws and pulvilli longer than 5th tarsomere; costa haired above and below; abdominal venter with pale yellowish-white hairs broadly on 1st sternite and ventromedian portion of syntergite 1+2 to 4th tergite.

Description. Body length: 6.2–10.0 mm.

Male. Head dichoptic, with dense, silvery-white pruinosity, upper fronto-orbital plate slightly grayish, upper occiput grayish; antenna black except dark brown arista; palpus black. Vertex 0.25–0.26 of head width; parafacial slightly narrowed below, subequal in width to postpedicel at mid height; gena about 0.4 of eye height. Inner vertical seta 4/5 as long as eye height; outer vertical seta absent; 1 outwardly-directed prevertical seta, about 3/4 as long as inner vertical seta; no proclinate orbital setae; 7–9 frontal setae; fronto-orbital plate with a few fine, black hairs on upper portion and 1–2 rows of rather sparse, fine, short, white hairs, the latter descending to upper 3/4 of parafacial; gena with a row of fine, short, white hairs on lower margin; postocular setae rather strong on upper portion, not close to posterior eye margin; occiput with several black hairs on upper portion and dense white pile. Base of antenna slightly above level of lower 1/3 of eye height; antenna falling short of lower margin of face by about 1/3 length of pedicel; pedicel with a long seta about twice as long as pedicel; postpedicel long, 3.5–4.0 times as long as pedicel; arista short plumose, total width including plumosity at most 1/2 as wide as postpedicel. Palpus about 4/5 as long as postpedicel. Eye almost bare.

Thorax black, with thin, grayish-white pruinosity on dorsum and rather dense pruinosity on pleura; dorsum with 3 broad longitudinal vittae on presutural area, fused with each other on anterior 2/3, and with a broad median vitta on postsutural scutum. One presutural and 1 postsutural acrostichal seta; 2 presutural and 3 postsutural dorsocentral setae; 2 postsutural intra-alar setae; scutellum with 3 pairs of marginal setae, basal setae as long as scutellum or slightly longer, apical setae about twice as long as scutellum; 2 katepisternal setae; lateral portion of postpronotal lobe and pleura with whitish hairs. Wing evenly and weakly tinged with pale brown; lower calypter translucent white; costa haired above and below; costal spine indistinct; relative lengths of costal sectors 2, 3 and 4 approximately 1.5:4.5:2; bend of vein M 1 about 1.5 times closer to wing margin than to dm-cu crossvein; last section of vein CuA 1 about 2/3 as long as dm-cu crossvein. Legs black, coxae with rather dense, grayish-white pruinosity; pulvilli pale brown; fore tibia with 3–4 anterodorsal and 2 posterior setae; mid tibia with 1 anterodorsal, 2 posterodorsal and 1 ventral setae; hind tibia with 3 preapical dorsal setae; claws and pulvilli longer than 5th tarsomere.

Abdomen nearly cylindrical, black, dorsum with dense, grayish-white pruinosity on anterior 1/2 of 3rd tergite, 2/5 of 4th and 1/3 of 5th tergites, pruinose band interrupted by broad median longitudinal vitta, venter with broader and thinner pruinosity. Hairs on dorsum black, pale yellowish-white on 1st sternite and ventromedian portion of syntergite 1+2 to 4th tergite; syntergite 1+2 with a pair of median discal setae, a pair of median marginal setae and a single lateral discal and lateral marginal seta on each side; 3rd to 5th tergites each with a pair of median discal setae and a row of marginal setae, lateral discal setae absent; 5th sternite with dense, black hairs mixed with pale yellowish hairs on median longitudinal area, postero-interior corner of posterior lobe sharply pointed. Terminalia: Sixth tergite entire, strongly constricted mid-dorsally, without hairs; surstylus slender, evenly narrowed to apex, with several long hairs; cerci in dorsal view rather slender, narrowed to apex, mid-dorsal suture very weak along basal 1/3 and distinct apically, in lateral view weakly constricted at basal 2/5, apical portion weakly curved ventrally; pregonite weakly pointed near middle; postgonite not extending beyond apex of epiphallus; dorsal sclerite of distiphallus curved dorsally at apex, apical membranous portion only slightly shorter than dorsal sclerite.

Female. Closely resembling male, but differing as follows: Vertex wider, 0.29–0.32 of head width; outer vertical seta about 1/2 as long as inner vertical seta; 2 proclinate orbital setae, anterior seta stronger and about 2/3 as long as inner vertical seta; antenna shorter, falling short of lower margin of face by about length of pedicel, postpedicel about 3.5 times as long as pedicel; mid tibia usually with 2 anterodorsal setae, rarely 3; claws and pulvilli shorter than 5th tarsomere; abdomen fusiform, with thinner pruinosity, dorsum of 3rd and 4th tergites with whitish pruinosity on anterolateral 1/2–1/3 and 5th tergite without pruinosity; whitish hairs on abdominal venter confined to 1st sternite, ventromedian portion of syntergite 1+2 and narrow anteroventral portion of 3rd tergite. Terminalia: Sixth tergite divided into 2 rather small hemitergites, each with a row of strong setae on posterior margin; 6th sternite long, with whitish hairs mixed with black hairs on posterior portion; 7th tergite divided into rectangular hemitergites, with a few rather long hairs on posterior portion; 7th sternite shorter than 6th, with whitish hairs, mixed with black hairs, on posterior portion; 8th hemitergite short, narrowly fused with hypoproct near middle, curved anteriorly on posterior portion; 8th sternite slightly shorter than 6th.

First instar larva: Body length 0.85–0.95 mm; cephaloskeleton rather broad on apical 1/2, dorsal margin nearly smooth; 2nd thoracic segment with 4–5 anterodorsal rows of fine spinules; 2nd to 6th abdominal segments each with 4–5 posteroventral rows of short fine spinules, 7th segment without posterolateral spinules.

Type material. Holotype ♂: CHINA / Sichuan, Kanding / Xiang, Zheduo Shan / 3000 m, 19–24.viii. / 1993, H. Shima ( IZCAS).

Paratypes: China, Sichuan: 1 ♂, 1 ♀, Jiuzhaigou, Daoban , 2400 m, 3.viii.1993, H. Shima ( IZCAS) ; 2 ♂♂, 1 ♀, Songfan Xian, Huanlong , 7.viii.1993, H. Shima ( IZCAS) ; 4 ♂♂, 6 ♀♀, Kanding Xiang, Yulin , 20.viii.1993, H. Shima & W. Zhang ( KUM) ; 28 ♂♂, 39 ♀♀, same locality and data as holotype, H. Shima, W. Zhang & A. Nakanishi ( BLKU, IZCAS, KUM) .

Etymology. The specific name is derived from Sichuan, the Chinese province in which this species was discovered.

Distribution. China (Sichuan).

Remarks. This species very closely resembles the Japanese species P. takanoi , but can be distinguished from it by the wider gena, mid tibia with only 1 anterodorsal seta in the male and 2 in the female, abdominal venter (and 5th sternite) broadly with whitish hairs and basal scutellar setae weak but distinct.

Figures

FIGURES 1–2. P. sichuana Shima & Zhang, sp. nov., arrows showing long costagial seta. 1. Left wing in dorsal view. 2. Same, detail of wing base.

FIGURES 87–90. Male terminalia of P. sichuana Shima & Zhang, sp. nov. 87. Epandrium, surstylus and cerci, dorsal view. 88. Same, lateral view. 89. Hypandrium, pre- and postgonite and phallus, lateral view. 90. Male 5th sternite, ventral view. Scale bars: 0.1 mm.

FIGURES 95–98. Female terminalia of Phyllomya spp., lateral view. 95. P. procera (Meigen). 96. P. rufiventris Shima & Chao. 97. P. sauteri (Townsend). 98. P. sichuana Shima & Zhang, sp. nov. Scale bars: 0.1 mm.

FIGURES 121–126. Phylomya spp. 121–123. Adult habitus/male head, lateral view. 121–122. P. sichuana Shima & Zhang, sp. nov. 123. P. takanoi Mesnil. 124–126. Female terminalia, lateral view. 124. P. arctogena Shima & Tachi, sp. nov. 125. P. chaoi Shima & Zhang, sp. nov. 126. P. sichuana sp. nov.

FIGURES 151–156. First instar larva and cephaloskeleton of Phyllomya spp., lateral view. 151–152. P. sichuana Shima & Zhang, sp. nov. 153–154. P. takanoi Mesnil. 155–156. P. volvulus (Fabricius).