Elasmostethus interstinctus ( Linnaeus, 1758 )

Jung, Sunghoon, 2017, Review of the genus Elasmostethus (Hemiptera: Heteroptera: Acanthosomatidae) from the Korean Peninsula, Zootaxa 4320 (2), pp. 351-365 : 353-354

Elasmostethus interstinctus ( Linnaeus, 1758)

Figs. 3, 4, 7, 8, 31, 32, 42, 49, 55

Cimex interstinctus Linnaeus, 1758: 445 (original description). Type locality: Europe.

Elasmostethus interstinctus: Josifov & Kerzhner (1978: 165) (record from North Korea, host plant), Kwon et al. (2001: 376) (bibliography, record from South Korea, distribution), Yamamoto (2003: 53) (in key, redescription, figures, records, distribution, host plants), Göllner-Scheiding (2006: 172) (catalogue, distribution), Aukema et al. (2013: 431) (catalogue, distribution).

Diagnosis. Recognized by abdominal mediotergites V–VII being entirely dark; the posterolateral angles of abdominal segment VII being produced far behind the posterior margin of the pygophore in the male; the presence of two pairs of submedian setal tufts (a shorter, comb-like upper, and a longer lower) on the ventral margin of the pygophore (Figs. 31, 42) and a pair of sclerotized and pigmented denticles ventrolaterally, immediately adjacent to the upper setal tufts ( Fig. 42 : ld); and the posterior margin of the eighth abdominal segment of the female being broadly emarginate in the middle (Fig. 32).

Measurements. ♂ / ♀. Body length 10.31–10.77/10.02–11.60; head width across eyes 1.94/1.81–2.04; lengths of antennal segments: scape 1.03–1.14/0.83–0.99, basipedicellite 1.68–1.80/1.28–1.46, distipedicellite 0.98–1.11/ 0.85–0.97, basiflagellum 1.64–1.72/1.37–1.54, distiflagellum 1.41–1.48/1.06–1.31; humeral width of pronotum 5.28–5.34/5.12–5.78; basal width of scutellum 2.79–2.84/2.76–3.20; length of scutellum 3.36–3.45/3.21–3.71; lengths of profemur and protibia 1.94–2.03/1.54–1.97, 1.80–1.89/1.58–2.00; lengths of mesofemur and mesotibia 2.35–2.36/2.00–2.41, 2.13–2.36/1.88–2.31; lengths of metafemur and metatibia 2.75–2.77/2.43–2.98, 2.81–3.55/ 2.44–3.12.

Material examined. SOUTH KOREA: Gangwon-do : Nodong-ri, Yongpyeong-myeon, Pyeongchang-gun, on Betula pendula , 16.viii.2014, WG. Kim (1 ♀ CNU) ; Mureung-ri, Nam-myeon, Jeongseon-gun, at light, 16.viii.2015, WG. Kim (2 ♂♂ 4 ♀♀ CNU). Gyeongsangbuk-do: Bangchongyo, Seo-myeon, Uljin-gun, 22.vii.2010, JW. Lee (1 ♂ 1 ♀ NIBR) ; Socheon-ri, Buseok-myeon, Yeongju-si, 25.v.2009, MH. Kim (1 ♂ NIBR). NORTH KOREA: Hwanghaenam-do: Mt. Kuwol , Unyul-myoen, M.I. Cho (1 ♂ 1 ♀ CNU) .

Distribution. Europe; Korea, China, Japan, Mongolia, Russia (Far East Territory), Armenia, Azerbaijan, Georgia, Asian part of Kazakhstan, Asian part of Turkey; North America.

Bionomics. The species is apparently associated with members of the plant family Betulacae. One specimen was collected on Betula pendula Roth ( Fig. 55 ) and others were collected at light during the present study. Previously it was recorded from Alnus sp. in Korea ( Josifov & Kerzhner 1978) and from Betula ermanii Cham. in Japan ( Yamamoto 2003).

Remarks. This species is easily confused with E. brevis and E. humeralis ; all of the three species are similar in appearance, and their pygophores are provided with two pairs of setal tufts on their ventral margin ( Figs. 41–43 ). Besides of the genitalia of both sexes, E. interstinctus can be distinguished from E. humeralis by the colour of the mediotergites of abdominal segments V–VII, and from E. brevis by the somewhat more angulate and more protruding humeral angle (Figs. 1–4). In living specimens the anterior portion of the scutellum of this species is provided with a distinct, deep red, more or less semicircular marking ( Fig. 55 ). The abdominal ventrites III–VII are marked with a pair of dark spots mesad of the spiracles (Figs. 7, 8).

Figures

FIGURES 41 – 47. Pygophores of Elasmostethus spp. 41 – 46. posterior view; 47. lateral view; 41. E. brevis; 42. E. interstinctus; 43. E. humeralis; 44, 47. E. yunnanus; 45. E. nubilus; 46. E. rotundus. Lettering: ld = lateral denticle; mp = median process; lt = lower setal tuft; ut = upper setal tuft. Scale bars: 0.5 mm.

FIGURES 54 – 59. Living specimens of Elasmostethus spp. 54. E. brevis; 55. E. interstinctus (on Betula pendula); 56. E. humeralis; 57. E. yunnanus (on Aralia cordata); 58. E. nubilus (on Aralia cordata); 59. E. rotundus.