Orius (Orius) nigromaritus, 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 : 396-398

Orius (Orius) nigromaritus sp. nov.

( Figs 3–4 , 11–14, 18 , 34–45 , 62 )

Type material. HOLOTYPE: ♁, NEPAL: MAKAWANPUR DIST.: Chitwan National Park, Machan Wildlife Resort , 27°32′07″N 84°44′17″E, sweep-netting male flowers of Mallotus sp. (probably M. philippensis ), 7–9 Nov. 2006, T. Yasunaga et al. ( NMTU) (AMNH_PBI 00380639).

Additional material examined. NEPAL: same data as for holotype, 2 ♀♀ ( TYCN).

Differential diagnosis. Recognized by its distinct sexual dimorphism ( Figs 3 vs. 4); very tiny size and shiny black body in male ( Fig. 3 ); bulbous male antennal segment II; dark femora except for pale extreme apex of metafemur; and generally slender paramere lacking denticule. Similar in tiny size and shape of paramere to O. takaii Yasunaga, 2000 currently known only from Okinawa Island of the Japanese Ryukyus; however, this Ryukyuan species has larger body and slender antennal segment II, and does not exhibit sexual dimorphism in coloration and size ( YASUNAGA 2000).

Description. Male. Macropterous. Body almost entirely black, very tiny in size; dorsal surface shining, with densely distributed pale, simple, semierect setae. Head shiny fuscous, rather short. Antenna yellowish brown, very short; segment II somewhat bulbous, much shorter than head width across compound eyes, about as long as eye height in lateral view (as in Fig. 35 ); segment III slightly shorter than IV. Labium shiny fuscous, reaching but not exceeding apex of procoxa. Pronotum and scutellum uniformly shiny fuscous, with distinct upright corner seta at each angle; calli rather narrow; pleura blackish brown; metathoracic scent efferent system as in Fig. 42 , with narrow peritreme. Hemelytron uniformly shiny fuscous; membrane pale smoky brown, semitransparent. Coxae and legs almost completely fuscous; protibial teeth rather sparsely and partly irregularly arranged; apex of metafemur narrowly yellow; pretarsal structures as in Figs 37–38 . Abdomen shiny fuscous. Male genitalia ( Figs 18 , 40–41 ): Paramere C-shaped, lacking denticule ( Fig. 40 ); conus sulcate apically ( Figs 41 , 62 ); basal 1/4 of flagellum thickened.

Female. Macropterous. Color pattern as in conventional Orius species and body generally paler and obviously larger than male; antenna slender; labium shiny pale brown; peritreme of metathoracic scent efferent system narrow ( Fig. 45 ; hemelytron widely pale brown except for fuscous cuneus. Female genitalia ( Fig. 63 ): Copulatory tube tiny, rather bulbous, with apical segment cleft, or grooved.

Measurements (mm). Male (holotype). Total length of body 1.29; head width across compound eyes 0.30; lengths of antennal segments I – 0.07, II – 0.17, III – 0.11, IV – 0.13; basal width of pronotum 0.58; maximum width across hemelytron 0.59; and lengths of metafemur 0.37, metatibia 0.38 and metatarsus 0.11.

Female (n=1). Total length of body 1.62; head width across compound eyes 0.32; lengths of antennal segments I – 0.10, II – 0.19, III – 0.17, IV – 0.18; basal width of pronotum 0.66; maximum width across hemelytron 0.71; and lengths of metafemur 0.46, metatibia 0.48, and metatarsus 0.11.

Etymology. From Latin, niger (black) combined with maritus (husband, man, male), indicating the black male adult of this new species; noun in apposition.

Biology. This anthocorid was found from inflorescence of Mallotus sp. ( Euphorbiaceae ), most probably identical to M. philippensis (Lam.) Muell.Arg. ( Fig. 12 ) grown in southern plain (subtropical climate zone) of Nepal ( Fig. 11 ). No other information on its feeding habit or life cycle is available.

Comments. Two available female specimens (collected together with the holotype male but herein excluded from the type series) are currently regarded to represent this new species, based on a concordance in shape of the metathoracic scent efferent system ( Fig. 45 ) and color pattern of the legs ( Fig. 4 ). Nonetheless, a definitive treatment will depend on acquisition of sufficient material and evidence through further field investigation.

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 34–45. Scanning electron micrographs of Orius nigromaritus sp. nov. (34–42 – ♁; 43–45 – ♀). 34–36, 44 – anterior body, left lateral view; 37 – protarsus; 38 – metatarsus; 39 – hind leg; 40 – male genital segment with paramere; 41 – basal parts of conus and flagellum; 42, 45 – scent efferent system, 43, left lateral habitus.

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.