Eurystylus jingfui Yasunaga, Nakatani & Chérot, 2017

Yasunaga, Tomohide, Nakatani, Yukinobu & Chérot, Frédéric, 2017, Review of the mirine plant bug genus Eurystylus Stål from Japan and Taiwan (Hemiptera: Heteroptera: Miridae: Mirinae), with descriptions of two new species, a new synonymy and a new combination, Zootaxa 4227 (3), pp. 301-324 : 308-311

Eurystylus jingfui Yasunaga, Nakatani & Chérot , n. sp.

Figs. 1 A, 3H–K, 4J–K, 5H, Table 1

Diagnosis. Recognized readily by its almost entirely fuscous body; golden vestiture on dorsum; pronotum lacking a pair of dark spots; rather conventional mirine shape of parameres ( Fig. 4 K); and simple, largely membranous endosoma, only with a primary lobal-sclerite ( Fig. 5 H). Externally most similar to E. costalis Stål ( Fig. 2 F) widely known from continental China, the Oriental Region and Pacific islands; distinguished by its mostly blackish dorsum, shorter labium not exceeding mesocoxa, and simple, largely membranous endosoma.

Description. Male ( Fig. 3 H–I): Body almost entirely fuscous, tumid; dorsum weakly shining, with black and golden vestiture ( Fig. 1 A, but vestiture easily rubbed off during collecting and mounting as in Fig. 3 H, J). Head black; vertex with small, pale spot adjacent to eye; frons with fuscous, velvety spot at base of antennal tubercle. Antenna largely blackish brown, with several pale or whitish parts; basal half of segment II dark reddish brown, with extreme base creamy white; bases of segments III and IV narrowly pale. Labium blackish brown, rather short, not exceeding base of mesocoxa; basal part of segment IV slightly pale. Pronotum weakly shining, with uniformly distributed, black, reclining setae and scattered golden or silvery pubescence (often missing in dry-preserved specimens); collar distinctly demarcated by deep groove especially on lateral sides, with ventral part whitish yellow; scutellum black, with pair of small pale spots near apex; thoracic pleurites dull black, pruinosed, with uniformly distributed, partly bundled, silvery setae except for ventral parts ( Fig. 3 I, K); margins of propleuron, mesoepisternum and metapleuron, and ventral 1/3 of epimeron whitish yellow; scent efferent system creamy white ( Fig. 3 I, K). Hemelytron almost entirely black, with uniformly distributed, dark, simple setae and scattered, golden pubescence; embolium with narrow, pale stripe along lateral margin; cuneus with pale, small spot laterally; membrane pale grayish brown, semitransparent, infuscate posteriad, with clearly fuscous veins. Coxae and legs almost uniformly black; each coxa with pale stripe on outer side; meso- and metatibiae often tinged with red in fresh specimen ( Fig. 1 A), each with creamy mark or ring medially ( Fig. 3 H̄K). Abdomen entirely black, largely with silvery vestiture. Male genitalia ( Fig. 4 J, K; 5H): Parameres of rather conventional mirine shape; hypophysis of left paramere moderately expanded; right paramere nearly straight. Endosoma largely membranous, with a single lobal-sclerite (PL). Female ( Fig. 3 J–K): As in male. Female genitalia: Not examined.

Measurements. ♂ / ♀: Total body length 5.8–7.0/ 7.0̄7.1; width of head across eyes 1.12̄1.20/ 1.20̄1.29; width of vertex 0.48̄0.49/ 0.56̄0.57; lengths of antennal segments ĪIV 1.19̄1.44, 2.50̄2.78, 0.69̄0.80, 0.54̄0.66/ 1.45̄1.52, 2.66̄2.74, 0.82̄0.84, 0.62̄0.63; length of labium 1.69̄2.12/ 2.14̄2.16; mesal length of pronotum including collar 0.96̄0.98/ 0.85̄1.03; basal width of pronotum 2.22̄2.36/ 2.48̄2.61; maximum width across hemelytron 2.37̄2.57/ 2.74̄3.02; and length of metafemur, tibia and tarsus 2.76̄2.88, 3.20̄3.44, 0.68̄0.72/ 3.01̄3.04, 3.56̄3.59, 0.68̄0.72.

Etymology. Named after Dr. Jing-Fu Tsai, our colleague and a promising Taiwanese heteropterist.

Biology. Adults of this new species were collected on inflorescences of Toxicodendron sp. ( Table 1), but immature stages are yet to be confirmed.

Discussion. This new species is readily distinguished from other congeners by the characters mentioned in the key and diagnosis above. The first author collected an undetermined (possibly undescribed) species very similar to E. jingfui from Indonesia (Sumatra), Peninsular Malaysia and Thailand; however, this SE Asian species is distinct in having the conspicuous, white striae on the lateral side of the body (thoracic pleura and proximal abdominal sterna). On the other hand, a male collected from subtropical plain in Nepal ( Fig. 1 A) is most probably conspecific with E. jingfui . Because this specimen is unfortunately teneral and the male genitalia were invisible, we refrain from including its definitive record in the present work.

Holotype ♂: TAIWAN: Kaohsiung City, Maolin District, Shanping Forest Ecological Garden, 22°58'20"N 120°40'44"E, 17 Oct 2015, Y. Nakatani ( AMNH _PBI 00380474) ( TFRI) . Paratypes. TAIWAN: 1♂ 2♀, same data as for holotype ( NIAES, TFRI) ; 2♂ 1♀, same data, except for date 18 Oct 2015 ( NIAES, NMNS) ; 1♂ 1♀, Kaohsiung City, Liouguei District, Zhong-Xing-Long Li, near Mt. Taiyuanshan , 19 Oct 2015, H. Yoshitake ( NIAES, TYCN) ; 5♂ 1♀, Taichung County, Kukuan , 730m, 20–22 Apr 1978, K.S. Lin & K.C. Chou ( NMNS) ; 1♀, Nantou County, Chunyang , Malaise trap (KCN), 11 May – 13 Jul 2004, C.S. Lin & W.T. Wang ( NMNS) ; 1♀, Nantou, Nanshanchi , 14 Apr (no further data, TYCN) .

Figures

FIGURE 1. Habitus images of Eurystylus species. A. Male adult from Chitwan, Nepal, identical to E. jingfui n. sp. B – C. E. ryukyus n. sp., female on Fraxinus griffithii. D. E. sauteri, female on Solidago canadensis, with Taylorilygus apicalis (Fieber) (upper) and Nysius plebeius Distant (middle). E – G. Ditto, male (E, G) and female (F) on Ligustorum japonicum. H, Ditto, head (velvety spots arrowed).

FIGURE 2. Habitus images of adult females and final-instar nymph (B – D) of Eurystylus species. A – B. E. coelestialium (image courtesy of M. Takai). C. E. sauteri Poppius. D. E. ryukyus n. sp. E. E. burmanicus from Chitwan, Nepal. F. E. costalis from Kathmandu Valley, Nepal.

FIGURE 3. Habitus images of dry-preserved specimens for E. sauteri (A – D), E. ryukyus n. sp. (E – G) and E. jingfui n. sp. (H – K).

FIGURE 4. Pygophore (A), left paramere (B, D, F, H, J) and right paramere (C, E, G, I, K) of Eurystylus species. A – C. E. ryukyus n. sp. D – I. E. sauteri. J – K. E. jingfui n. sp.

FIGURE 5. Endosoma and adjacent structures of Eurystylus species. A – C. E. ryukyus n. sp. D – G. E. sauteri Poppius. H. E. jingfui n. sp. I – J. E. coelestialium. Scale bars 0.2 mm.