Lyrosoma pallidum (Eschscholtz 1829)

Body (Fig. 1) general carabid-shape, yellowish brown to reddish brown, surface glossy with microsculpture. Male. BL: 4.3–5.1 mm. Head as long as wide or slightly wider than long (HL/HW: 0.94–1.00); eyes medium and prominent, separated by about 5 times of eye width; eye about 0.8 times as long as temple; short setae present between facets, shorter than facet diameter; vertex of head without pale mounds; epistomal suture indistinct; epicranial suture more or less Y-shaped; dorsal surface with rather dense isodiametric microsculpture, ventral surface with transverse microsculpture. Antenna filiform, about 3 times as long as HW, antennomere 2 shortest, 3 and 11 longest, 4–7 similar in shape and length, 9–10 with dense sensilla in apical grooves, 9–11 very weakly clubbed. Labrum (Fig. 2) transverse; anterior margin deeply and broadly emarginate; anterior and each anterolateral margin distinctly membranous and transparent; 4–6 long setae and single very long seta present on membranous part of each side of midline; 3–4 spinose setae present on each anterolateral region of membranous part; anterior margin of membranous part with dense micro setae; sclerotized part with two setae on each side of midline and one seta on each anterior corner; surface of sclerotized part with many pores scattered sparsely. Mandibles (Fig. 3) symmetrical, inner regions without tooth; broad at base and pointed at apex; dorsal and ventral surface with many pores on medial area. Maxilla (Fig. 4) with 4 palpomeres; palpomeres 2–4 with distinct setae. Labium (Fig. 5) with 3 palpomeres; palpomeres 1–2 with long setae, last palpomere asetose; ligula caudal fin-like shape and bilobed, each lobe with 7–10 long setae on subapical region; ligula with many pores on medial and subapical regions of each lobe; paraglossa broadly developed, anterior margin with many setae densely distributed. Mentum trapezoidal narrowing apically; anterior margin straight; single long seta present on each anterolateral region; many pores scattered sparsely and microsculpture transverse. Submentum with many pores, short setae present sparsely. Pronotum broad cordiform, wider than long (PL/PW: 0.81–0.84); pronotum widest near anterior third; anterior corners round, posterior corners angled; pronotum without mid-basal fovea; disc with shallow and broad medial-longitudinal depression. Elytra oval and convex, gradually increased to posteriorly in convexity; longer than wide (EL/EW: 1.41–1.59); each elytron with 9 striae; intervals as wide as width of first antennomere, weakly convex and impunctate, dense isodiametric microsculpture present; basal lateral margin weakly serrate; epipleura without distinct punctures. Hind wings absent. Mesoventrite glabrous and sculptured strongly; mesoventral process sharp, contiguous to metaventral process. Metaventrite covering many setae sparsely, metaventral process sharp. Pro- and mesotarsi dilated, tarsomere 1−4 with numerous setae ventrally. Metatarsi simple and long; last tarsomere about 1.8 times as long as tarsomere 4. Tarsal claws simple, basal part with very feeble tooth; two empodial setae present, as long as tarsal claws. Abdominal sternites covering many setae, surface with dense isodiametric microsculpture. Aedeagus (Figs 7–10) without paramere; median lobe long and slender, middle part of apex slightly protruded (Fig. 9); structure of internal sac as in Figs 8 and 10. Female. BL: 4.6–5.2 mm. Basically not differ to male. Pro- and mesotarsi not dilated. Sternite VIII (Fig. 6) with posterior margin emarginate narrowly, a few setae present on marginal region; spiculum ventrale broad, deeply emarginate anteriorly.

Korea (new record), Russia (Kamchatka, Kuriles, Magadan, Sakhalin) and Japan (Hokkaido, Honshu), Figure 11.