Lyrosoma pallidum (Eschscholtz)

Yoo, In-Seong, Sikes, Derek & Ahn, Kee-Jeong, 2013, A redescripton of Lyrosoma pallidum (Eschscholtz) and distributional range extension of Lyrosoma Mannerheim (Coleoptera, Agyrtidae), ZooKeys 329, pp. 23-32 : 24-27

Lyrosoma pallidum (Eschscholtz) Figs 1-10

Pteroloma pallidum Eschscholtz, 1829: 7.

Lyrosoma ovipenne Lewis, 1893 (synonymy by Schawaller 1998)

Lyrosoma suturale Lewis, 1893 (synonymy by Schawaller 1998)

Lyrosoma chujoi Mroczkowski, 1959 (synonymy by Schawaller 1998)

Lyrosoma ituropense Hlisnikovský, 1964 (synonymy by Schawaller 1998)

Material.

KOREA: Gangwon Prov.: 1♂1♀, Goseong-gun, Hyeonnae-myeon, Daejin-harbor, 38°29'59.1"N, 128°25'46.2"E 9 m, 29 V 2012, IS Yoo, JH Song, seaweeds on seawall; 1♂ (dissected), Sokcho-si, Daepo-dong, Oeongchi-beach, 38°11'01.3"N, 128°36'31.9"E 21 m, 28 V 2012, IS Yoo, JH Song, under seaweeds; RUSSIA: 15♂15♀ (1♂1♀ on slide, 8♂7♀ in 80% EtOH), Kamchatka, Petropavlovsk-kamchatsky, Avacha Bay, 53°01'26.4"N, 158°38'31.3"E, 25 VII 2011, KJ Ahn, IS Yoo, under debris on seashore; 2♂2♀ (7♀ in 80% EtOH), Kamchatka, Petropavlovsk-kamchatsky, Rescue Bay, 52°49'31.8"N, 158°35'51.1"E, 27 VII 2011, KJ Ahn, IS Yoo, seaweeds on rocky shore; 1♀ (in 80% EtOH), Kamchatka, Petropavlovsk-kamchatsky, Rescue Bay, 52°49'31.8"N, 158°35'51.1"E, 27 VII 2011, KJ Ahn, IS Yoo, seaweeds on sandy beach; JAPAN: 44♂54♀ (1♂1♀ on slide, 24♂30♀ in 80% EtOH), Hokkaido, Os hima, Minami-kayabe, Ôfuna, 42°00'01.9"N, 140°52'55.4"E, 7 VI 2012, KJ Ahn, IS Yoo, decaying seaweeds/starfish on seawall; 1♂, Hokkaido, Akkeshi, Tokotan, 15 VI 1994, K. J. Ahn, on rock crevice in high tide; 3♂18♀, Hokkaido Prov., Nemuro City, Hamamatsu, 26 IX 2000, H.-J. Kim, M.-J. Jeon, under stones.

Redescription.

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, mid dle 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.

Distribution.

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