Paradieuches dissimilis (Distant, 1883), 2019

Vinokurov, N. N., 2019, Paradieuches dissimilis (Distant, 1883) - new genus and new species of seed bug (Heteroptera: Lygaeidae) in the fauna of Russia from the South of the Far East, Russian Entomological Journal 28 (1), pp. 1-4 : 1-4

Paradieuches dissimilis (Distant, 1883)

Figs 1–8 .

Dieuches dissimilis Distant, 1883: 483 ; Lethierry, G. Severin, 1894: 219; Oshanin, 1912: 38; Ishihara T., 1953: 112; Miyamoto, 1957: 73.

Paradieuches dissimilis : Scudder, 1962: 770.

MATERIAL. 1 ♀ — Russia: Kuril Is. , Small Kuril Ridge , western part of Polonsky Is., 1– 8.07.2017, Yu. Sundukov, L. Sundukova, ( ZIN); 1 ♂ — Japan: Hokkaido, Tomakomai Experimental Forestry Station, Iburi District , 18– 22.07.1997, N. Vinokurov, ( IBPC) .

MORPHOLOGY. Female. Body rather narrow, elongated, 3.1 times as long as wide. Body length 5.5 mm, body width behind middle of hemelytra 1.75 mm ( Fig. 1 ). Head, pronotum and scutellum black, dull, hemelytra shiny.

Head extending forward, shorter than wide, with protruding clypeus, very finely punctated. White adpressed pubescence sparse on frons and denser on head sides, between antennae, on clypeus and on underside of head. Ocelli widely separated, located behind eyes. Bucculae low, ending at level of antennal tubercles. Labium reaching middle coxae; Labial segment I reaching prothorax, brown; other segments yellowbrown. Antennae with short pale setae, segments I and II dirty yellow, mesial surface of segment I with prominent spinules basally and apically, segment III black with brown base, segment IV black. Length of antennal segments: I — 0.7, II — 1.1, III — 1.0, IV — 1.1 mm.

Pronotum trapeziform, width at base, with lateral margins straight, smoothly narrowing toward apex, posterior margin deeply emarginate. Pronotal disc black, shallowly depressed behind middle, distinctly punctated, with punctation sparse on elevated callus areas, with very short white hairs located in punctures. Lateral margins of pronotum laminate, yellow along their entire length, wide in posterior half, narrowing anteriorly, with thin black edging.

Thoracic venter dimly lustrous with silvery tinge, deep coarse punctation and very short white setae; scent gland area dull. Fore femora thickened, brown, with one large denticle and two rows of small denticles at middle. Middle and hind femora, all tibiae and tarsi dirty yellow. Tibiae with sparse pale spinules and short setae. Hind tarsomere I twice as long as tarsomeres II and III combined.

Scutellum sparsely punctated. Hemelytra reaching tip of abdomen, weakly concave before middle, weakly dilated in posterior half. Clavus with three rows of brown-black punctures, whitish yellow generally, yellow along inner margin, brownish apically. Corium whitish in basal half, with interrupted black band at middle, apical part brown to dark brown; with two rows of coarse dark punctures along inner margin and with fine, often colourless punctures along veins, distal half with sparse black punctation. Membrane translucent, with 3 yellowish spots basally, yellow apically, with large bluish black spot at middle.

Abdomen black, with rather dense short adpressed golden hairs.

REMARKS. For comparison, I examined a conspecific male from Hokkaido Island ( Fig. 2 ). Body length 5.1 mm, maximal width 1.2 mm, length to width ratio 3.1. Pronotum with concave lateral margins. Coloration paler than in female from the Polonsky Island: legs yellow, pattern on posterior half of corium dark brown, membrane white basally and apically, brownish black at middle.

The genus Paradieuches belongs to the tribe Drymini Stål, 1872 and the subfamily Rhyparochrominae . The genus is known from South-East Asia [ Slater, 1964; Slater, O’Donnel, 1995] and includes only two species: P. lewisi Distant, 1883 , endemic to southern islands of the Japanese archipelago, and P. dissimilis , distributed over the whole genus’ range, in Japan as far northwards as Hokkaido Island, on the Korean Peninsula, and in the South-West and South-East of China [ Tomokuni, 1998; Péricart, 2001].

The endemic genus Hidakacoris Tomokuni, 1998 was also described from the Japanese archipelago. Its only species, T. tsutsii (Hidaka, 1963) is distributed on Honshu, Shikoku, and Kyushu islands. The two genera are very close and reveal great external similarity but they clearly differ in the details of aedeagus morphology [ Tomokuni, 1998].

Of the 11 species of the tribe Drymini occurring on the Kuril Islands, species of the genus Eremocoris Fieber, 1860 , namely E. abietis (Linnaeus, 1758) ( Fig. 9 ), E. insularis Kerzhner, 1977 , and especially E. angusticollis Jakovlev, 1881 ( Fig. 10 ) resemble P. dissimilis in the body length and the shape of the pronotum and particularly lamelliform lateral pronotal margin. However, the mentioned species of Eremocoris clearly differs from P. dissimilis in the bicolored pronotal disc, with a black anterior part and a pale to brown posterior part, and also in the hemelytral membrane having a large white spot near the posterior margin of the corium. By contrast, in species of the genus Paradieuches the pronotal disc is entirely black while the membrane is pale, translucent, with a large black or brown-black, diffusely outlined spot in the middle.

Acknowledgments. I am very grateful to Yu.N Sundukov and L.A. Sundukova (Kurilsky Nature Reserve) for the opportunity of examination of the bugs collected in the South Kurils in 2017 and F. V. Konstantinov (St. Petersburg) for valuable comments and editing the manuscript. This work was financially supported by the Siberian Branch of the Russian Academy of Sciences, project AAAAA – A17-117020110058-4 (2017–2020), and the Russian Foundation for Basic Research, project 18-04-00464 (2018– 2021).

Figures

Figs 1–8. Paradieuches dissimilis: 1–2 — habitus; 3–4 — genital capsule; 5–8 — paramere in various positions; 1 — ♀, Polonsky Is.; 2–8 — ♂, Hokkaido Is.; 1–3 — dorsal view; 4 — lateral view. Рис. 1–8. Paradieuches dissimilis: 1–2 — внеШний вид; 3–4 — генитальнаЯ капсула; 5–8 — парамер в раЗных положениЯх; 1 — ♀, о. Полонского; 2 — ♂, о. Хоккайдо; 1–3 — сверху; 4 — сбоку.

Figs 9–10. Eremocoris spp: 9 — E. abietis, ♀ (Eastern Siberia, South-Eastern Yakutia); 10 — E. angusticollis, ♀ (Kunashir Is.). Рис. 9–10. Eremocoris spp: 9 — E. abietis, ♀ (ВосточнаЯ Сибирь, Юго-ЗападнаЯ ЯкутиЯ); 4 — E. angusticollis, ♀ (о. КунаШир).