The family Ectopsocidae, belonging to the superfamily Homilopsocidea of the suborder Psocomorpha, currently comprises 228 species of six genera in the world (Bess and Lienhald, 2023). This family includes small, generally brown psocids which are sometimes common on foliage and are particularly abundant on dead leaves. This group usually lay eggs in batches on foliage, and nymphs sometimes aggregate under loose webbing (New and Lienhard, 2007).

In Korea, one species, Ectopsocopsis cryptomeriae (Enderlein, 1907), has been recorded in this family (Soysouvanh et al., 2017). In this paper, the genus Ectopsocus is newly recorded from South Korea with Ectopsocus briggsi McLachlen, 1899. We provide pictures and illustration of diagnostic characters, distribution.

Materials and Methods

Sixteen specimens of Ectopsocus briggsi were collected in Ulsan-si, Geoje-si, Jinju-si, and Jeju-do in 2022. The specimens were divided into microtubes for each individual, immersed in 90% ethanol, and kept in a freezer. After storage, the specimens’ entire bodies, wings, and heads were observed using LEICAM205C. Reproductive organs were observed through a LEICADM6B. In order to observe morphological characteristics of reproductive organs, after abdominal division, 10% sodium hydroxide solution was treated in, and then preparats were made using Canadian balsam.

Abbreviations of parts measured are as follows: FW, HW: lengths of right fore- and hind- wings, F, T, t1 and t2: lengths of femur, tibia and tarsomeres 1 and 2 of right hind leg, respectively, Mx4: length of IV palpomere, of right maxillary palpus, f1-fn: lengths of flagellomeres 1-n, of right antenna, ctt1: number of ctenidobothria on t1, IO: minimum distance between compound eyes, D: antero-posterior diameter of right compound eye, d: transverse diameter of right compound eye, all in dorsal view of head, PO: D/d

Terminology and morphological characters of adult, wing venation, and terminalia were followed Yoshizawa (2005) and Li (2002).

Taxonomic Accounts

Family Ectopsocidae Roesler, 1944

Genus EctopsocusMcLachlan, 1899 외다듬이벌레속(신칭)

Ectopsocus briggsiMcLachlan, 1899 외다듬이벌레(신칭) (Figs. 1-2)

Ectopsocus parvulusKolbe, 1882: 451-486.

Ectopsocus briggsiMcLachlan, 1899: 277.

Ectopsocus limbatusNavas, 1909: 156.

Ectopsocus borealisHarrison, 1916: 134.

Ectopsocus punctatusThornton and Wong, 1968: 137.

Description. Female. The segments of the antenna are a total of 13 nodes. The prothorax has black stripes on both sides. The dorsal view of the abdomen has light brownish stripes, and the ventral view is white (Fig. 1B). The forewings' R-M veins are very short or single point, and the around is dark without Areola postica. The periphery of the edge of each vein is also pale dark (Fig. 1D). The subgenital plate has two lobes, and each lobe is curved inward. Each lobe has a total of three setae, one inward and two outwards, and six long setae between the lobes (Fig. 1E). Marginal spine of paraprocts are symmetric (Fig. 1F, G).

Male. The color is similar to the female, but the male is a little darker. The body size is relatively smaller than the female (Fig. 2B, C; Table 1). The clypeus is smaller than the female, but the stripe pattern is clear. Compared to females, rates of IO/d are small (Table. 1). The antennae are longer than females. The clunium is exposed on the dorsal surface of the abdomen. Two prominent areas of black tubercles are present front and back of clunium. The smaller area forms a row which in side view is steep-sided (Fig. 2F).

Specimens examined. 3♂, 8♀ Gyeongsang National University, Gajwa-dong, Jinju-si, Gyeosangnam-do, Korea, 7. ⅶ. 2022, leg. J.Kim; 1♂, 2♀ 3-8 Bangeo-Dong, Dong-gu, Ulsan-si, Korea, 26. ⅵ. 2022, leg. J.Kim; 1♂ 262-5 Galgot-ri, Nambu-myeon, Geoje-si, Gyeosangnam-do, Korea, 30. ⅶ. 2022; 1♂, 1♀ 2479 Yeon-dong, Jeju-si, Jeju-do, Korea, 1. ⅶ. 2022, leg. J.Kim.

Host plant.Dendropanax trifidus (Thunb.) Makino ex H. Hara, Euonymus japonicas (Thunb.), and Trachycarpus fortune (Hook.) H.Wendl. (in this study). Wide range of trees, shrubs and other microhabitats like leaf litters were known as hostplants (Alexander, 2016).

Remark.E. briggsi is distinguished from Ecopsocopsis cryptomeriae by coloration, female’s bilobed subgenital plate, and male’s clunial ornamentation.

Distributions. Korea (New record), Japan, Russia, Mongolia, England, Bulgaria, Cyprus, Serbia, Iran, Israel, Tunisia, Algeria, Spain, Portugal, Nepal, India, Indonesia, Congo, Kenya, Nigeria, Zimbabwe, USA, Mexico, Chile, Venezuela, Micronesia, Norfolk Island, Australia, Tanzania, New Zealand.