Punctifulvius kerzhneri Schmitz, 1978

(Figs 1A, 2I–K, 7D–F, 8C–G, 9G–L, 10C–F)

Material examined. JAPAN: 3♂, 4♀, Hokkaido, Tokachi, Ashoro, Kyushu Univ. Exp. Forest, on bed logs for cultivation of Shiitake-mushroom, 43.25, 143.55, 5. VIII. 1997, T . Yasunaga (AMNH, TYCN) ; 1♂, 4♀, Honshu, Aomori Pref., Towadako Town, Tsuta, 40.59, 140.96, 23. IX. 1997, T . Ozaki (TYCN) ; 5♀, Gunma Pref., Oze, Tokura, 36.84, 139.25, 7. VIII. 1955, S. Gotoh (TYCN) ; 4♂, 4♀, Wakayama Pref., Tanabe City, Ohtoh, Mengawa, 33.686, 135.596, 15. VI . 1998, T . Yasunaga (TYCN, ZRC) ; 5♂, 3♀, Shikoku, Kochi Pref., Kami City, Befu, Monobe, 33.77, 134.03, 18. VII - 15. Aug. 1998, M. Takai (TYCN) . RUSSIA: 1♂, 2♀, Primorskij Kraj, Khasanskij Dist., Kedrovaja Pad’ Nature Reserve, 22. VIII. 1963, I. M. Kerzhner (holotype ♂ & subsequently identified 1♂, 1♀, ZMAS) ; 1♀, Primorskij Kraj, “Kedrovaja Pad” Nature Reserve, Khasanskij Ditst., Kerzhner 27.VII.1982 (DZUS) .

Diagnosis. Recognized principally by its generally dark brown, ovoid body, without reddish tinge; distinctly punctate dorsum, head and thoracic pleurites; creamy yellow coxae; and pale brown femora each with two obscure, apical annulations; distinct subapical tooth on claw; tumid left paramere with inflated hypophysis and basal thumblike process; relatively elongate, parallel-sided right paramere; V-shaped sclerite in vesica (Fig. 8E); and a pair of weakly sclerotized rings on seminal depository (anterior membranous sac, cf. Fig. 8F). Further diagnostic characters including the male and female genitalic structures were provided by Yasunaga (1999); structures of female posterior wall and first ovipositor are as shown in Figs 8G and 10D–F (first SEM documentation). The final instar nymph is recognized by its generally whitish coloration; widely darkened apical parts of the antennomeres II and III; pale brown, more or less mottled pronotum, mesonotum and wing pads; and sanguineous annulations on abdominal terga (Fig. 2J–K).

Measurements. See Table 1.

Distribution. Japan (Hokkaido, Honshu, Shikoku, Kyushu), Korea (including Jeju Island), Russia (S. Primorsky Territory) (Fig. 12) (Schmitz 1978; Yasunaga 2000; Kim et al. 2019).

Biology. This temperate species is known widely from evergreen and deciduous forests in eastern Asia. Yasunaga (2000, 2001) suggested P. kerzhneri has a univoltine life cycle, and the immature forms are found from late May to early June. Within natural forest zones, rotten logs and decaying woods grown with polypolaceous fungi appear to be the principal habitats of this cylapine. However, it also inhabits bed logs for the cultivation of Shiitake-mushroom, Lentinula edodes (Berk.) Pegler.

Remarks. P. kerzhneri is most similar to P. aquilonius, P. austellus and P. parvus in sharing the entirely fuscous hemelytra (Figs 1A, 5A) and punctate head (Figs 5A, B, 9G). From P. parvus it can be distinguished by the larger body and the presence of a pronotal collar (Fig. 9G). From P. aquilonius it can be distinguished by the lack of longitudinal rib on posterior lobe of pronotum (Fig. 9G).