Orius (Orius) ekaii, Yasunaga & Yamada & Duwal, 2019

Yasunaga, Tomohide, Yamada, Kazutaka & Duwal, Ram Keshari, 2019, Three new species of the flower bug genus Orius (Hemiptera: Heteroptera: Anthocoridae) from Nepal, Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 59 (2), pp. 391-401 : 393-395

Orius (Orius) ekaii sp. nov.

( Figs 1–2 , 7–8 , 17, 21–33 , 61 )

Type material. HOLOTYPE: ♁, NEPAL: RASUWA DIST.: Langtang Himal National Park , Lama Hotel ~ Thomna, 2,340~ 2,800 m alt., 28°09′32″~10′54”N 85°25’48″~26′29″E, sweep-netting flowers of Quercus semecarpifolia Sm. , 3 Jun 2006, T. Yasunaga ( NMTU) ( AMNH _ PBI 00380638 ) . PARATYPES: NEPAL: RASUWA DIST.: same data as for holotype, 3 ♁♁ ( TYCN); Lama Hotel ~ Rimche, 2,400~ 2,500 m alt., 28°09′32~41″ N 85°25′17 ~48″E, sweep-netting flowers of Quercus semecarpifolia , 8 Jun 2006, T. Yasunaga, 2 ♁♁ 1 ♀ ( TKPM, TYCN).

Differential diagnosis. Recognized by its relatively large size among congeners belonging to the nominotypical subgenus; elongate body with developed forewing membrane; oily shiny, impunctate pronotum; wide peritreme of scent efferent system; uniformly yellowish brown legs; and broadened basal half of flagellum of paramere. Combination of these characters, in addition to its unique arboreal habitat, enables this new species to be distinguished from any other known congeners that belong to Orius s. str. Based on the similarly large size and basally thickened flagellum of the paramere, O. ekaii sp. nov. is most similar to O. tomokunii Yamada & Yasunaga, 2016 described from North Thailand ( YAMADA et al. 2016); the former can be readily distinguished from the latter by more expanded posterior angle of the pronotum, darkened cuneus, and the shape of the paramere (e.g., denticule situated near the base of flagellum and basal half of flagellum thickened as in Fig. 61 ).

Description. Male. Macropterous. Body generally pale brown, large, elongate oval; dorsal surface shining, with uniformly distributed pale, simple, reclining setae. Head shiny fuscous, weakly porrect. Antenna pale brown, thickened; basal half of segment I, apical 1/4–1/3 of segment II, whole segment III, and base of segment IV more or less darkened; segment II slightly shorter than head width across compound eyes, about as thick as protibia. Labium somber brown, reaching but not exceeding apex of procoxa; apical 1/3 of segment III and base of segment IV yellowish brown. Pronotum polished, oily shiny, sparsely and minutely punctate posterior to calli, with distinct upright corner seta at each angle; scutellum uniformly shiny dark brown, flat; pleura dark brown; metathoracic scent efferent system as in Figs 24, 33 , with wide peritreme. Hemelytron shiny pale brown; cuneus almost entirely darkened ( Figs 1–2 ); membrane pale grayish brown, developed, wider than hemelytron. Coxae and legs pale brown; apical part of each coxa slightly pale; protibial teeth reddish brown, rather blunt-tipped; pretarsal structures as in Figs 26–27 . Abdomen shiny dark brown, generally elongate. Male genitalia ( Figs 21 , 28–29 , 61 ): Paramere C-shaped, with denticule situated near base of flagellum ( Figs 28 , 61 ); conus tapered toward apex; flagellum short, with thickened basal half.

Female. Macropterous. Similar in general coloration and shape to male, but body ovoid, antenna slender and hemelytron not significantly infuscate. Female genitalia: Not examined as only a single teneral specimen is available.

Measurements (mm). Male (n = 4). Total length of body 2.25–2.40; head width across compound eyes 0.38–0.41; lengths of antennal segments I – 0.09–0.11, II – 0.30–0.36, III – 0.21–0.25, IV – 0.19–0.20; basal width of pronotum 0.85–0.95; maximum width across hemelytron 0.93–0.96; and lengths of metafemur 0.58–0.67, metatibia 0.71–0.76, and metatarsus 0.20–0.22.

Female (n = 1). Total length of body 2.25; head width across compound eyes 0.39; lengths of antennal segments I – 0.10, II – 0.29, III – 0.19, IV – 0.20; basal width of pronotum 0.85; maximum width across hemelytron 1.01; and lengths of metafemur 0.65, metatibia 0.71, and metatarsus 0.19.

Etymology. Named after [the Shramana] Ekai Kawaguchi (1866–1945), a Japanese Buddhist monk and pathfinder famed for his amazing fantastic pilgrimage from India via Nepal to Tibet across the Himalayas, seeking Sanskrit and Tibetan Buddhism scriptures (cf. KAWAGUCHI 1909). He also is known as the first Japanese visitor to Nepal and Tibet. Noun in genitive case standing in apposition.

Biology. This unique arboreal new species was discovered from inflorescence of Quercus semecarpifolia Sm. (Fagaceae) , on which two undetermined species of Anthocoris Fallén, 1814 and more than five species of the Miridae co-occurred, such as Castanopsides katsutai Yasunaga & Duwal, 2008 , C. michaili Yasunaga & Duwal, 2008 , Liocapsus langtang Yasunaga & Schwartz, 2007 , and Psallomorpha quercicola Duwal, Yasunaga & Lee, 2010 (cf. YASUNAGA & SCHWARTZ 2007, YASUNAGA & DUWAL 2008, DUWAL et al. 2010). Orius ekaii most probably fed on a few undetermined thysanopteran species found simultaneously and/or the oak pollen (T. Yasunaga, personal observation).

Figures

Figs 1–6. Habitus images of Nepalese Orius species, live individuals. 1–2 – O. ekaii sp. nov., ♁; 3–4 – O. nigromaritus sp. nov. (3 – holotype ♁, AMNH_PBI 00380639; 4 – ♀); 5–6 – O. paveli sp. nov. (5 – ♁; 6 – ♀).

Figs 7–12. Habitats of Nepalese Orius species. 7–8 – full blossom of Quercus semecarpifolia, on which O. ekaii sp. nov. was found, 9 – sweeping inflorescence of Q. semecarpifolia, 10 – Urtica dioica, with two adults of O. paveli sp. nov. (arrows), 11 – Chitwan National Park in southern Nepal, type locality of O. nigromaritus sp. nov., 12 – male flowers of Mallotus philippensis, considered to be breeding host of O. nigromaritus sp. nov.

Figs 13–21. Dorsal habitus (13–17), and male (18–19, 21) and female (20) genitalia of Nepalese Orius species. 13–14, 18 – O. nigromaritus sp. nov.: 13 – holotype ♁ (AMNH_PBI 00380639); 14 – ♀; 18 – pygophore with paramere. 15–16, 19–20 – O. paveli sp. nov.: 16 – holotype ♁; 17 – ♀; 19 – pygophore with paramere; 20 – female genital segments with copulatory tube, dorsal view. 17, 21 – O. ekaii sp. nov.: 17 – holotype ♁; 21 – pygophore with paramere. Scale bars: 0.5 mm for 13–17; 0.1 mm for 18–21.

Figs 22–33. Scanning electron micrographs of Orius ekaii sp. nov. (22–30, 33 – ♁; 31–32 – ♀). 22–23, 25 – anterior body, left lateral view; 24, 32–33 – metathoracic scent efferent system: 25 – protibia, 26 – protarsi, 27 – metatarsus; 28–29 – male genital segment with paramere, 30 – evaporative area of scent efferent system.

Figs 61–65. Male (61–62, 64) and female genitalia (63, 65) of Nepalese Orius species. 61 – O. ekaii sp. nov., 62–63 – O. nigromaritus sp. nov., 64–65 – O. paveli sp. nov.