Neuroctenus quercicola Nagashima & Shono, 2003

(Fig. 4E–H)

Material examined. South Korea. Jeollabuk-do: 1 ♂, 1 ♀, Byeonsan Peninsula (35.681333, 126.589028), 20.vi.2021, coll. Minsuk Oh (SNU) . Jeju-do: 3 ♂, 5 ♀, Jeju-si, ‘ Seongpanag’ [=Seongpanak trail, Mt. Halla], 10.ii.1999, coll. Seung-Hwan Lee (SNU) ; 6 ♂, 3 ♀, Jeju-si, Jocheon-eup, Seonheul Gotjawal (33.511696, 126.714689), 18.vii.2021, coll. Wonwoong Kim (SCNU) ; 1 ♂, 1 ♀, same locality, 05.viii.2023, coll. Wonwoong Kim (SCNU); 1 ♂, 6 ♀, Jeju-si, Jocheon-eup, Gyorae National Recreation Forest (33.439092, 126.670338), 18.vii.2021, coll. Wonwoong Kim (SCNU) ; 2 ♂, 1 ♀, same locality, 11.vi.2022, coll. Wonwoong Kim (SCNU); 3 ♂, 3 ♀, same locality, 04.viii.2023, coll. Wonwoong Kim (SCNU); 3 ♀, Seogwipo-si, Namwon-eup, Hannam Experimental Forest (33.333083, 126.652583), 12.vi.2022, coll. W. Kim, S. Park, S. Lee (SNU) .

Distribution. Korea (Jeollabuk-do, Jeju Island), Japan (Honshu, Shikoku) (Nagashima & Shono 2003).

Comments. Nagashima & Shono (2003) reported that this species is frequently found under the bark of evergreen Quercus (subgenus Cyclobanopsis) and Castanopsis species ( Fagaceae). We also collected large number of individuals of various development stages under the bark of recently dead broadleaved trees, such as Quercus acuta Thunb. ( Fagaceae), Castanopsis sieboldii (Makino) Hatus. ( Fagaceae), and Cornus macrophylla Wall. ( Cornaceae) in Jeju Island.

This species is similar with Neuroctenus taiwanicus Kormilev, 1955 in Korea, but can be distinguished by having following characteristics: externally exposed area of male pygopore cordiform; paratergite VIII of females less rounded, almost trapezoidal at both posterolateral corners (Nagashima & Shono 2003).