Elasmostethus amabilis, Yamamoto, 2003

Elasmostethus amabilis View in CoL sp. n.

( figs. 4, 15-16, 23, 30, 36)

Elasmostethus sp.1 : Sato, 1998: 373.

Type material. – Holotype 3, Kogen-onsen , Kamikawa, Hokkaido, Japan, 24.viii.2001, A. Yamamoto ( SEHU) . – Paratypes: Hokkaido: 23, same locality as holotype, 14.vi.1998, A. Yamamoto ; 33, same locality as holotype, 6.viii.2001, A. Yamamoto ( OMO) ; 23 2♀, same data as holotype ( SEHU) ; 33 2♀, Motomachi, Maruseppu , 30.vii.2000, Y. Kida ( OMO) ; 13, Nukabira , Kamishihoro, 2.vi.1951, S. Kato ( NIAS) ; 43, Toyokura , Otaru, 9.vi.2002, I. Tadaki ( OMO) . Honshu: 193 21♀, Hikinuma, Ibigawa , Shiobara, Tochigi Pref., 18.vi.1988, K. Sato ( TPMU) ; 13, Mt. Hakusan , Ishikawa Pref., 29- 31.viii.1960, T. Hidaka ( NIAS) ; 13, Mt. Daisen , Tottori Pref., 13.x.1987, T. Komatsu ( SEHU) .

Description. – Body ovoid, noticeably small; dorsal surface pale green with red markings, densely dark punctate; ventral surface greenish yellow, reddish on posterior end. Head pale green, irregularly punctate except around eyes and with a pair of fuscous, narrow stripes on basal part of tylus. Antenna green, with brownish segment III, fuscous IV and V. Rostrum greenish yellow with fuscous apex, reaching to middle or hind coxae. Pronotum pale green, reddish along posterolateral margin, densely punctate except for calli; humeral angle slightly projected, infuscate posteriorly. Scutellum pale green, tinged with red basally, densely punctate; apex pale, impunctate. Corium translucent, pale green, with some red along claval and membranal margin, densely punctate; base of vein R+M narrowly blackish; apical corner slightly infuscate; clavus red, densely punctate; membrane hyaline, with a triangular, fuscous marking at middle of costal margin. Femur greenish yellow, slightly darkened apically and with a small basal tubercle in male; tibia green, brownish apically; tarsus brown, infuscate on apex of tarsomere II; apex of claw fuscous. Abdominal terga entirely black, except for broadly greenish yellow lateral margins; lateral yellow area usually as broad as connexivum; posterior margin of segment VII reddish yellow. Connexiva greenish yellow, reddish on apex of segment VII. Sterna greenish yellow, impunctate; each segment with a pair of fuscous spots laterally; segment VII reddish on apical corners. Pendergrast’s organs semicircular ( fig. 36).

Male genitalia: Sides of genital capsule strongly rounded; ventral rim projecting strongly, deeply emarginate at middle, furnished with a pair of lower tufts and with a pair of black teeth at each side of the lower tufts; upper tufts absent; infolding of dorsal rim with a pair of long setal tufts at each side of middle ( figs. 15- 16); paramere with narrow triangular outer projection strongly reflexed caudad ( fig. 23); phallotheca with a large dorsal diverticulum; dorsal lobe of conjunctival sheath developed and divided into 5 lobules; extreme right lobule (in the figure) somewhat reduced ( fig. 30).

Female genitalia: Posterior margin of genital segments VIII rounded and lacking median emargination; posterior corner of segment IX protruding slightly beyond posterior margin of segment VIII ( fig. 36).

Dimensions. – 3/ ♀: Body length 8.19-10.01 (8.80)/8.37-10.01 (9.06); width of head including eyes 1.73-1.86 (1.78)/1.69-1.86 (1.77); length of antennal segment I 0.79-1.00 (0.87)/0.69-0.83 (0.76), II 1.38- 1.73 (1.57)/1.07-1.31 (1.20), III 0.83-1.04 (0.94)/ 0.72-0.90 (0.82), IV 1.35-1.59 (1.48)/1.17-1.45 (1.29), V 1.17-1.41 (1.31)/1.10-1.24 (1.16); width of pronotum 3.80-4.62 (4.20)/3.86-4.59 (4.29), width of scutellum 2.07-2.55 (2.30)/2.14-2.66 (2.41), length of scutellum 2.38-3.04 (2.67)/ 2.48-3.04 (2.79); length of fore femur 1.69-2.04 (1.86)/1.55-1.83 (1.69), fore tibia 1.73-2.00 (1.87)/ 1.59-1.79 (1.70), middle femur 1.79-2.14 (1.97)/ 1.76-2.04 (1.87), middle tibia 1.73- 2.07 (1.93)/1.73-2.07 (1.87), hind femur 2.48-3.00 (2.76)/2.21-2.69 (2.43), hind tibia 2.48-3.04 (2.77)/ 2.21-2.69 (2.45).

Etymology. – The name is an adjective; from Latin ‘amabilis’ (= cute), referring to the small habitus.

Distribution. – Japan (Hokkaido, Honshu).

Biology. – Sato (1998) found many adults on Toisusu urbaniana (Seemen) ( Salicaceae ) in Kuroiso, Tochigi Pref., Honshu. Recently I found many eggs and young instar nymphs on this plant in Kamikawa, Hokkaido, and confirmed this host association. This species mainly occurs in the montane zone in Hokkaido and Honshu and can be found in the streamside forest. The adults are often attracted to light.

Remarks. – This new species is similar to E. interstinctus in appearance. It can be recognized by the remarkably smaller body, the broad yellow lateral margins of the abdominal terga, the strongly projecting ventral rim of the male genital capsule and the lack of the upper tufts ( figs. 15-16), the shape of the paramere ( fig. 23), and the female genital segment IX that protrudes beyond the posterior margin of VIII ( fig. 36).