Physopelta (Neophysopelta) quadriguttata Bergroth, 1894

(Figs. 1E–G, 3F, 4F, 5H, 6F, 7F, 8F, 9F, 10F, 11F, 12F, 13E, 14E)

Physopelta quadriguttata Bergroth, 1894: 160 . Syntypes: macropterous 2 ♀, India: Sikkim; MZHF? (Stehlík 2013: 540).

References. Esaki (1926: 157) (distribution); Blöte (1931: 100) (distribution); Kerzhner (2001: 246) (checklist: Palaearctic); Stehlík (2004: 3) (distribution); Miyamoto et al. (2005: 11) (distribution); Rédei et al. (2009: 13) (monograph); Kohno et al. (2012: 400) (monograph); Aukema et al. (2013: 401) (checklist: Palaearctic); Stehlík (2013: 540) (monograph); Zheng & Lin (2013: 15) (distribution); Ito (2015: 55) (distribution); Ishikawa (2016: 478) (checklist: Japan); Zhou & Rédei (2020: 5) (female genitalia).

Material examined. Non-types (macropterous 66 ♂♂ 41 ♀♀) , JAPAN: Ryukyu Islands: Yaeyama Islands: Ishigaki Is., Nosoko Forest Road, 21.iv.1999, light trap, leg. K. Takahashi (1 ♀, TUA) ; Iriomote Is., Hoshidate, 18.xi.2004, light trap, leg. M. Hayashi (1 ♀, TUA) . TAIWAN: Yilan County: “Taiheizan (Taihoku-shû)” [= Datong Township, Mt. Taiping-shan ?], 26.vii.1932, leg. K. Sato (1 ♂, ELKU) ; as above but 24.x.1932 (2 ♀♀, ELKU) . Kaohsiung City: Taoyuan District, Baoshan, near Mt. Jianfu-shan, 23°03'07.6"N 120°44'42.7"E, 1350m alt., 3.iv.2018, light trap, leg. Y. Fukuda, S. Shimamoto & S. Taru (33 ♂♂ 22 ♀♀, TUA) ; Taoyuan District, Mt. Jianfu Shan, 23°02'39.4"N 120°44'42.7"E, 26.iv.2019, leg. S. Shimamoto (15 ♂♂ 4 ♀♀, TUA) . Taipei City: Wulai District, 4.v.1968, leg. Y. Watanabe (1♀, TUA) . Chiayi County: Alishan Township, 17.v.1968, leg. H. Sawada (1 ♂ 1 ♀, TUA) . Nantou County: Ren’ai Township, 24°07'38.4"N 121°15'88.8"E, 19.v.2016, light trap, leg. N. Kaneko and Y. Tamadera (15 ♂♂ 8 ♀♀, TUA) ; Nanshanchi, 16.v.1971, leg. K. Sakai (1 ♂ 1 ♀, TUA) .

Diagnosis. Recognized among other species of Physopelta by a combination of the following characters: only macropterous morph known; body 2.8 times as long as maximum width across fore wings (Fig. 1C–E); calli and disc of pronotum pale brown, with orange margins (Fig. 5H); scutellum brown, with numerous pale callosities; membrane of fore wing pale brown (Fig. 6F); abdominal sternites paler brown with dark brown lunulae on sutures (Figs. 3F, 4F); compound eye more than 0.3 times as wide as vertex in dorsal view; antennomere I shorter than antennomere II; antennomere II nearly clavate; calli in male convex; punctures of scutellum denser in central part than in marginal part, as large as punctures of pronotum; anterior margins of fore wings not parallel to each other in rest; procoxal projection present, horn-shaped, curved, less than 1.5 times as long as its maximum width (Fig. 7F); protrochanteral wrinkles present; male profemur more than 2 times as wide as mesofemur at widest part of each; male protibia lacking tooth at apex, with a single row of denticles throughout its length ventrally; peritreme of scent gland ostiole crescent-shaped, protruding posterolaterad (Figs. 8F, 10F); infolding of ventral rim of genital capsule less convex in middle part (Fig. 9F); outer margin of endophallic reservoir outgrowth emarginate in apical part (Fig. 11F); stem of paramere not emarginate in basal part (Fig. 12F); crown of paramere at apex convex in posterior view; and inner margins of ring sclerites not parallel to each other (Fig. 13E).

Description of genitalia. Genital capsule (Fig. 9F) spherical, semicircular in ventral view, smooth on surface; infolding of ventral rim less convex in middle part. Phallus (Fig. 11F) oblong; capitate process membranous; basal plate and phallotheca coriaceous; conjunctiva with two pairs of partly sclerotized conjunctival appendages; endophallic reservoir with a pair of outgrowths; outer margin of outgrowth emarginate in apical part. Paramere (Fig. 12F) longer than its maximum width across crown; stem not emarginate in basal part; crown at apex convex in posterior view.

Female terminalia (Fig. 13E) triangular in anterior view; valvulae VIII and IX combining to form an ovipositor, fused with valvifers VIII and IX, respectively; ring sclerites coriaceous in marginal part, membranous in central part, protruding inward, with inner margins not parallel to each other. Spermatheca (Fig. 14E) membranous; apical receptacle spherical; intermediate part in width uniform; spermathecal duct apically widened.

Remarks. In terms of general appearance, Physopelta (Neophysopelta) quadriguttata strongly resembles Ph. (N.) redeii, but the former can be distinguished from the latter by the body form, which is 2.8 times as long as maximum width across the fore wings. In contrast, Ph. (N.) redeii has the body 2.5 times as long as the maximum width across the fore wings.

The teratological from in pronotum is found in Ph. (N.) quadriguttata (Figs. 1G, 5H). The calli of this individual is more convex in the left part than in the right part. In Neophysopelta, sexual dimorphism in the swelling degree of the calli and similar dimorphism between larger and smaller male has been known as mentioned in the previous section. In this individual, the left and right parts of the calli represents dimorphism between larger male and female/smaller male, respectively.

Distribution. Japan: Ryukyu Islands (Ishigaki Island, Iriomote Island) (Miyamoto et al. 2005; Kohno et al. 2012; Ito 2015; present study); Taiwan (main island) (Esaki 1926; Kerzhner 2001; Rédei et al. 2009; Stehlík 2013; Zheng & Lin 2013; present study); China (Stehlík 2013); India (Bergroth 1894); Laos (Stehlík 2013); Nepal (Stehlík 2004); Thailand (Stehlík 2013); Vietnam (Stehlík 2013).

Host plant. In Taiwan, this species was collected from Mallotus paniculatus (Lam.) Müll. Arg. (Euphorbiaceae), and Dendrocalamus latiflorus Munro. (Poaceae) (Zheng & Lin 2013), but nymphs have not been collected to date. Therefore, the “true” host plant for Physopelta (Neophysopelta) quadriguttata is still unknown.

Biology. Adults are attracted to artificial light (Rédei et al. 2009; Zheng & Lin 2013; present paper).