Scoloposcelis koreanus Jung & Yamada, sp. nov.

Scoloposcelis koreanus Jung & Yamada, sp. nov.

(Figs. 1–4, 6–7)

Diagnosis. Body elongate, parallel-sided, and shiny; outer half of clavus, basal half of endocorium and embolium light brown; membrane yellowish brown, almost transparent, remainder of hemelytra black to blackish brown; fore femur with a row of spinules ventrally; mid- and hind femora without spinule; paramere blade-like, sharp at apex; copulatory tube membranous, swollen at apex.

Description. Body (Fig. 1) entirely black, elongate, shiny. Head black, smooth on dorsal surface, sparsely covered with short setae; two pairs of long, erect setae present on sides of tylus; vertex about twice as wide as eye in dorsal view; eyes blackish brown, prominent; ocelli reddish brown. Antennal segment I black, stout, reaching to apex of head, covered with short setae at apex; segment II black, shorter than width of head across eyes, thickened toward apex, covered with suberect setae; segments III and IV yellowish brown, shorter than segment II, covered with suberect setae of variable length; segment IV flattened, a little longer than segment III; lengths of antennal segments I–IV (male/female) 0.12–0.14/0.14–0.15, 0.33–0.36/0.35–0.38, 0.23–0.25/0.25–0.27, and 0.27–0.29/ 0.29–0.33. Labium reaching middle of mesosternum, with very short setae; segment I to basal half of segment III black; apical half of segments III and segment IV yellowish brown; lengths of labial segments II–IV (male/female) 0.21–0.22/0.21–0.22, 0.50/0.52, and 0.33–0.34/0.31–0.35.

Pronotum (Fig. 1) black, trapezoidal, smooth on apical half of dorsal surface, weakly depressed on posterior half, bearing erect setae at anterior and posterior angles; collar dark brown, distinct, with short setae; posterior margin concave, almost twice as long as anterior margin. Scutellum black, smooth, shiny covered with setae. Hemelytra parallel-sided, sparsely covered with silky, white setae; outer half of clavus, basal half of endocorium and embolium light brown, inner basal area of membrane whitish transparent, remainder of hemelytra black to blackish brown; Ostiolar peritreme and evaporatorium brown; ostiolar peritreme crescent, not acute at apex, not reaching anterior margin of metapleuron. Legs covered with short, silky setae; fore femur black, ventrally with row of 10–15 spinules of various size; fore tibia and fore tarsus pale yellow; mid- and hind femora black, without spinules ventrally; mid- and hind tibiae and tarsi pale yellow.

Abdomen dark brown, densely covered with short setae; scissures on abdominal tergite reaching posterior margin of segment III. Uradenia with balloon-shaped secretory body (Fig. 6). Male genitalia with cup-shaped pygophore, covered with long setae posteroventrally; paramere blade-like, sharp at apex, with large groove on middle part (Figs. 4, 7). Female genitalia swollen at apex with membranous, twisted copulatory tube.

Measurements (male/female). Body length 2.20–2.55/2.56–2.90; Head length (excl. neck) 0.33–0.34/0.38– 0.44, width (incl. eyes) 0.40–0.42/0.42–0.43; vertex width 0.20–0.22/0.21–0.22; distance between ocelli 0.11– 0.13/0.15–0.16; anterior pronotal width 0.31–0.35/0.32–0.35; basal pronotal width 0.71–0.82/0.81–0.85; maximum width across hemelytra 0.65–0.79/0.71–0.83.

Type series. Holotype: 3, under the bark of bed log, Quercus acutissima Carruth. (Fagaceae), shiitake mushroom farm, Hoengseong-gun, Gangwon-do, Korea, 4.x.2007, S. Jung leg.; Paratypes: 123, 7ƤƤ, same data as holotype (with glass slide No. SNU# HEM 473–480 for genitalia; Figs. 3–6); 303, 15ƤƤ, shiitake mushroom farm, Hoengseong-gun, Gangwon-do, Korea, 5.iv.2008, S. Jung leg. The holotype and paratypes are preserved at the SNU (Insect collections, Laboratory of Insect Biosystematics, Research Institute for Agricultural and Life Sciences, Department of Agricultural Biotechnology).

Distribution. Korea (middle part).

Remarks. In general appearance, this new species is similar to Scoloposcelis albodecussata. It can be distinguished from the latter (characteristics in parenthesis) by the relatively smaller body size, 2.2–2.9mm (2.5– 2.95mm), vertex being about one and half as wide as the eyes (Fig. 1) (vertex about twice as wide as eye), paramere with large groove, sharp at apex (Figs. 7, g & pt) (paramere with very narrow groove, weakly projecting at apex), relatively longer and twisted copulatory tube, narrowed apically (Fig. 3) (copulatory tube curved, bellows-like, broadened apically), the secretory body (sb) of uradenia as shown on Fig. 6 (Fig. 5 for S. albodecussata).

Recently, this new species was tested using DNA barcoding (partial sequences of the cytochrome c oxidase I; Jung et al. in press). Additionally this new species were also used as a terminal taxon, Scoloposcelis sp., on reconstructing of the molecular phylogeny of the flower bugs based on the complete 18S rRNA and partial 28S rRNA of the D3 region in the nuclear and 16S rRNA in the mitochondria (Jung et al. 2010). The genetic divergences of the above four DNA regions between the sister species also supported a unique species level of this new species among the Anthocoridae.

This new species also resemble S. parallela and S. pulchella, but from which it can be separated by the structure of ventral surface of femora. This new species have the fore femur with a row of spinules and mid- and hind femora without spinule. However, S. parallela have fore- and hind femora with a row of spinules and mid femur smooth, and S. pulchella have fore femur with two rows of spinule and mid- and hind femora smooth. In the structure of male genitalia, this new species can differ from them by the paramere with large groove and sharp at apex (with narrow groove and strongly acute at apex in S. parallela; with wide groove, gradually narrowed toward apex and weakly spinulate in apical half in S. pulchella).

Biology. The new species inhabit between barks of dead oaks, Quercus trees in the middle part of Korea, whereas S. albodecussata occurs under the barks of dead Castanopsis in the Ryukyus, mainly on Ishigaki and Iriomote Islands in Japan (cf. Yamada & Hirowtari 2005). Many specimens, including all adults and nymphs, were collected from the barks of dead oaks, Quercus acutissima Carruth. (Fagaceae), the bed logs of the shiitake mushroom. This new species are mainly found from the bed logs damaged by the shiitake pests such as Camptomyia spp. (Diptera: Cecidomyiidae; Fig. 2). As the congeners are predators of bark beetles and other tiny arthropods that occur under the bark of conifers or deciduous trees (cf., Carayon 1954a, 1956; Muraleedharan & Ananthakrishnan 1974; Péricart 1996; Yamada & Hirowatari 2005), the new species seems to be a natural enemy of the pests in the shiitake mushroom farm.

Etymology. Named after the type locality, the Korean Peninsula.