The genus Eudectus Redtenbacher containing seven species are distributed in the Holarctic region. Four species have been recorded in East Asia (Zerche, 1990, 1993; Herman, 2001; Smetana, 2004). Little is known about the habitat and ecology of Eudectus species, but they are usually found in cold place (Zerche, 1990) and overwinter as a larva (Steel, 1970). Our specimens were collected by a net while they were flying in a group or by sifting leaf litters.

Members of the Eudectus are characterized by the combination of following characters: body parallel-sided, gently convex, covered with coarse punctures and fine pubescence; eyes large and protruded, ocelli distinct; pair of dorsal tentorial pits present deeply; gular sutures divergent posteriorly; labrum transverse; mandible elongate and curved inwardly with large internal tooth; maxillary palpomere 3 oval and expanded, palpomere 4 glabrous, much smaller and slender than 3; pronotum hexagonal, more or less convex and transverse, broader than head, lateral margin crenulated and angulated around middle; postcoxal process tetragonal, protrochantin almost concealed; abdomen more or less broad and flat; tergite III covered with spicules almost all over; anterior three fourth of paratergite III covered with distinctly coriaceous sculpture; pair of oval patches of wing-folding spicules present on medial part of tergite IV; tergite VII with apical palisade fringe; front tarsus broad in male; lateral part of sternite III with oblique carina (Watanabe, 1990; Zerche, 1990).

In this paper, we report E. japonicus Zerche and E. rufulus for the first time in Korea. We also provide habitus photographs, redescriptions of these two species with illustrations of diagnostic features, and a key to Korean species. The specimens for this study are deposited in the Chungnam National University Insect Collection (CNUIC), Daejeon, Korea.

Taxonomic accounts

Genus Eudectus Redtenbacher 넓은가슴네눈반날개속(신칭)

EudectusRedtenbacher, 1857: 245; Zanetti, 1987: 424; Watanabe, 1990: 351; Zerche, 1990: 142; Newton et al., 2000: 342.

Eudectoides Campbell, 1978: 11 (synonymized by Zerche, 1990: 144).

Type species: Eudectus giraudi Redtenbacher

Key to Korean species of the genus Eudectus Redtenbacher

1. Head, thorax and elytra brown to reddish brown, abdomen dark brown (Fig. 1A); antennomere 3 more or less gradually dilated apically and longer than wide, 4–8 less transverse (Fig. 2F); postero-lateral margin of pronotum clearly emarginated (Fig. 2G); metaventrite without marking; median lobe of aedeagus longer than paramere (Figs. 2L–M) ··················· ··························································· E. japonicus Zerche

- Head, thorax and elytra yellowish brown, abdomen brown but basal and apical segments darker (Fig. 1B); antennomere 3 more or less abruptly dilated apically and slightly longer than wide, 4–8 strongly transverse (Fig. 3A); postero-lateral margin of pronotum almost straight or obscurely emarginated (Fig. 3B); metaventrite with dark tri-markings; median lobe of aedeagus slightly shorter than paramere (Figs. 3G–H) ···· ···································································· E. rufulus Weise

Eudectus japonicusZerche, 1990 넓은가슴네눈반날개(신칭)

(Figs 1A, 2)

Eudectus japonicusZerche, 1990: 157; Herman, 2001: 402; Smetana, 2004: 254; Watanabe, 2013: 77.

Description.

Body length 2.5–2.7 mm. Body (Fig. 1A) more or less convex and parallel-sided, covered with coarse punctures and pubescence; reddish brown to dark brown, more or less glossy. Head pentagonal transversely, punctate coarsely and sparsely, about 1.4 times wider than long; eye about 2.0 times longer than temple; distance between ocelli about 1.4 times longer than distance between outside of ocellus and inner margin of eye; antennae (Fig. 2F) relatively short and stout, gradually incrassate distally, reaching to just below pronotum, antennomeres 1–5 more or less glossy; scape robust, about 1.3 times longer than wide; pedicel suboval, about 1.2 times longer than wide, slightly narrower and shorter than scape; antennomere 3 about 1.5 times longer than wide, slightly narrower and longer than pedicel; 4–6 suboval, 7 subpentangular and 8–10 subquadrate, 4–10 slightly transverse and getting larger distally; 4 about 1.14 times wider than long and 0.69 times shorter than 3; 7 about 1.11 times wider than long; 9 about 1.15 times wider than long; 11 about 1.64 times longer than wide. Pronotum subhexagonal transversely, more or less convex medially and deplanate laterally, covered with coarse punctures; lateral margins more or less serrate; widest around middle, about 1.5 times wider than long, about 1.3 times wider and 1.2 times longer than head; anterior and posterior margins crenulated weakly, anterior margin almost straight and posterior one more or less arcuate; anterior angles round and posterior one more or less angulate obtusely; elytra more or less flat, covered with coarse punctures; lateral margins almost straight with weak crenulation and slightly dilated posteriorly; about 1.1 times wider than long, about 1.5 times wider and 1.8 times longer than pronotum; posterior margin truncated.

Male.

Abdominal tergite VIII (Fig. 2H) with more or less emarginated posterior margin; more or less sclerotized setae present on medial part of sternite VII; posterior margin of sternite VIII roundly emarginated weakly (Fig. 2I). Aedeagus (Figs. 2L–M) trilobed and almost symmetrical; median lobe narrowed apically with acute apex rather sclerotized, lateral margin almost straight, much longer than basal bulb and paramere, dorsal surface covered with few scattered punctures; paramere more or less stout, more or less curved inwardly in apical half, covered with scattered punctures.

Female.

Abdominal tergite VIII (Fig.2J) with narrowly truncated posterior margin; posterior margin of sternite VIII more or less prolonged with round apex (Fig. 2K).

Materials examined.

Total 312 specimens. KOREA:Chungbuk Prov.: Cheongju-si, Heungdeok-gu, Biha-dong, Mt. Bumosan, N36˚38´4.8˝E127˚24´43.1˝172 m, 29 IV 2009, YH Kim, YG Ban, SG Lee, sweeping [165♂♂ 144 ♀♀(4♂♂2 ♀♀on slide), CNUIC]; same data except for under bark (1♀, CNUIC); Chungnam Prov.: Nonsan-si, Beolgok-myeon, Surak-ri, Mt. Daedunsan, Surak-valley, N36˚08´04.2˝ E127˚18´29.1˝362 m, 19 IV 2013, SG Lee, JS Lee, MA Cho, leaf litter (1♂, CNUIC); Jeju Prov.: Jeju-si, Chuja-myeon, Is. Hachujado, 22 VIII 2002, YB Cho [original label as ‘Korea, Jejudo Chujado Island (hachujado) VIII. 22. 2002. Y. B. Cho’] (1♀, CNUIC).

Distribution.

Korea, Japan.

Eudectus rufulusWeise, 1877 배무늬넓은가슴네눈반날개 (신칭)

(Figs 1B, 3)

Eudectus giraudi var. rufulus Weise, 1877: 96.

Eudectus rufulus: Weise, 1884: 270; Sharp, 1889: 473; Nakane, 1971: 83; Zerche, 1988: 362; 1990: 146; 1993:343; Watanabe, 1990: 353; 2013: 77; Herman, 2001: 402; Smetana, 2004: 254.

Description.

Body length 2.4–2.6 mm. Body (Fig. 1B) more or less convex and parallel-sided, covered with coarse punctures and pubescence; yellowish brown to brown, more or less glossy. Head pentagonal transversely, punctate coarsely and sparsely, about 1.6 times wider than long; eye about 2.1 times longer than temple; distance between ocelli about 2.0 times longer than distance between outside of ocellus and inner margin of eye; antennae (Fig. 3A) relatively short and stout, gradually incrassate distally, reaching to posterior margin of pronotum, antennomeres 1–5 more or less glossy; scape robust, about 1.4 times longer than wide; pedicel suboval, about 1.2 times longer than wide, slightly narrower but rather shorter than scape; antennomere 3 about 1.1 times longer than wide, slightly narrower and shorter than pedicel; 4–8 subpentangular and 9–10 subquadrate, 4–10 transverse and getting larger distally; 4 about 1.36 times wider than long; 7 about 1.35 times wider than long; 9 about 1.24 times wider than long; 11 about 1.41 times longer than wide. Pronotum subhexagonal transversely, more or less convex medially and deplanate laterally, covered with coarse punctures; lateral margins more or less serrate; widest around anterior two fifth, about 1.5 times wider than long, about 1.3 times wider and longer than head; anterior and posterior margins crenulated weakly; anterior margin almost straight and posterior one more or less arcuate, anterior angles round and posterior one more or less angulate obtusely; elytra more or less flat, covered with coarse punctures, lateral margins almost straight with weak crenulation and slightly dilated posteriorly; about 1.2 times wider than long, about 1.4 times wider and 1.8 times longer than pronotum; posterior margin truncated.

Male.

Abdominal tergite VIII (Fig. 3C) with more or less emarginated posterior margin; more or less sclerotized setae present on medial part of sternite VII; posterior margin of sternite VIII weakly emarginated roundly (Fig. 3D). Aedeagus (Figs. 3G–H) trilobed and almost symmetrical; median lobe slightly shorter than basal bulb and paramere, lateral margin in basal three fourth almost straight and parallel-sided, apical fourth narrowed apically with acute apex; paramere more or less stout, curved inwardly in apical two third, covered with scattered punctures.

Female.

Abdominal tergite VIII (Fig. 3E) with more or less rounded posterior margin; posterior margin of sternite VIII more or less prolonged with round apex (Fig. 3F).

Materials examined.

Total 7 specimens. KOREA: Gangwon Prov.: Pyeongchang-gun, Jinbu-myeon, Mt. Odaesan, Sangwonsa, 15 IX–14 XI 2001, KJ Ahn, CW Shin ex FIT (1♀, CNUIC); Chungnam Prov.: Daejeon-si, Seo-gu, Jangan-dong, Mt. Jangtaesan, N36˚13´03.3˝ E127˚20´36.2˝258 m, 28 III 2012, DH Lee, TK Kim, SG Lee, leaf litter (1♂1♀, CNUIC); Gyeongnam Prov.: Geoje-si, Dongbu-myeon, Geoje Natural Recreation Forest, N34˚47´16.9˝ E128˚37´23.4˝213 m, 14 IV 2011, YH Kim, sifting, flood debris [3♂♂1♀(2♂♂1♀on slide), CNUIC].

Distribution.

Korea, Japan.