Taxon classification Animalia Coleoptera Staphylinidae

Atheta (Microdota) formicetorum Bernhauer, 1907 Figs 2, 28, 37, 46, 55, 64, 73

Atheta (Microdota) formicetorum Bernhauer, 1907: 400; Paśnik 2001: 206; Smetana 2004: 385 (as valid species).

Atheta (Amidobia) formicetorum: Sawada 1974: 162 (as valid species).

Material examined.

Syntype, 1♀, labeled as in Fig. 84. NORTH KOREA: 1 ex., Corea sept. Kangvon–do 9-14 X 1991 [North Korea, Gangwon Prov., 9-14.x.1991]. SOUTH KOREA: Chungbuk Prov.: 3 exx., Danyang-gun, Yeongchun-myeon, Mt. Taehwasan, 14. vii– 14.viii.2001, KJ Ahn, SJ Park, CW Shin, FIT;; Chungnam Prov.: 5 exx., Daejeon-si, Dong-gu, Daeseong-dong, Mt. Sikjangsan, Secheon park, 30.vii.2000, MH Kim, mushroom; 10 exx., Gongju-si, Banpo-myeon, Sangsin-ri, Mt. Gyeryongsan, 26.viii.2001, MH Kim, mushroom; Gangwon Prov.: 46 exx., Yangyang-gun, Seo-myeon, Mt. Seoraksan, Osaekyaksu, 16.viii.2000, MH Kim, mushroom; Gyeongbuk Prov.: 51 exx., Sangju-si, Hwanam-myeon, imgok-ri, Mt. Cheongtaesan, 10.ix.2000, MH Kim, mushroom; 11 exx., same data as the former except ‘27.vii.2001’; 3 exx., Uljin-gun, Onjeong-myeon, Mt. Baekamsan, Sinseon valley, 12.viii.1999, HJ Kim, mushroom; Gyeonggi Prov.: 3 exx., Yangju-gun, Jangheung-myeon, Songchu-ri, Mt. Bukhansan, 26. vii– 31.viii.2001, KJ Ahn, SJ Park, CW Shin, FIT.

Description.

Length 1.8-2.5 mm. Body (Fig. 2) subparallel-sided, surface glossy, densely pubescent. Body usually reddish yellow to yellowish brown; head almost black; abdominal segment VI darker than other segments. Head . Slightly transverse, approximately 1.1-1.2 times wider than long, widest across eyes, slightly narrower than pronotum; eyes distinctly large and prominent, about 1.8-2.0 times longer than tempora; infraorbital carina complete; gular sutures moderately separated; cervical carina complete. Antennae (Fig. 28) long and slender, dilated apically; antennomeres 1-3 elongate, 1 longest, 4-10 distinctly transverse, 11 longer than wide, about as long as preceding two combined. Mouthparts. Labrum transverse, anterior margin emarginate; two lateral sensilla and about 11-12 macrosetae present on each side of midline; α-sensillum setaceous, about twice as long as ε-sensillum, β- and γ-sensilla reduced. Mandibles asymmetrical, pointed apically, about 1.6-1.7 times as long as basal width; many denticles present in molar region; right one with small internal tooth, anterior margin serrulate; prostheca developed. Lacinia of maxilla with seven spines in distal comb region, two isolated spines present, distal comb region and isolated spines narrowly separated; maxillary palpus elongate, with pubescence and long setae; palpomere 1 about 1.6-1.8 times longer than wide, 2 about 2.5-2.6 times longer than wide, 3 slightly longer than 2, about 2.6-2.8 times as long as wide, 4 digitiform, filamentous sensilla reaching to apical half. Labium with ligula narrowly long, divided into two lobes in basal half; two medial setae narrowly separated; two basal pores closed together; lateral pseudopores, one setal pore and two real pore present on each side of prementum; palpus elongate, with many setulae; palpomere 1 largest and dilated basally, about 1.5-1.7 times longer than wide, with γ-setula close b-setula, 2 shortest, about 1.4-1.6 times longer than wide, 3 slightly dilated apically, about as long as 1, about 3.0-3.5 times longer than wide. Thorax. Pronotum distinctly transverse, approximately 1.3-1.4 times wider than long, widest in apical third; pubescence directed anteriorly in midline. Metanotal scutum with one long seta and about 3-4 short setae on each side of midline; mesocoxal cavities narrowly separated, mesoventral process pointed at apex, as long as or slightly longer than isthmus and metaventral process combined; length ratio of mesoventral process, isthmus and metaventral process 16:5:10. Elytra slightly wider than pronotum; elytron approximately 1.5-1.6 times longer than wide, pubescence directed posteriorly and postero-laterally; postero-lateral margin almost straight; hind wings fully developed; flabellum composited about four setose lobes. Legs. Slender and long, with dense pubescence and setae; tibiae with two spurs at apex; length ratio of tarsomeres 22:24:25:65 (protarsus); 26:29:29:32:64 (mesotarsus); 35:33:31:30:69 (metatarsus); one empodial seta present, shorter than claw. Abdomen. Parallel-sided, widest at middle, surface fairly glossy and densely pubescent, with imbricate microsculpture; macrochaetal arrangement of tergites II–VI 01-02 (or 12)-12-12-13;; male tergite VII with small and round tubercle in postero-median region; male tergite VIII (Fig. 37) with 4 macrosetae on each side of midline, posterior margin with two outer processes and two inner processes, outer process narrower and longer than inner process; male sternites VI–VII with many pores in anterior margin, VIII with 8 macrosetae on each side of midline, posterior margin convex, crenate in median region; posterior margin of female tergite VIII emarginate; posterior margin of female sternite VIII slightly emarginate at middle, with conspicuous and short marginal setae; minute setae present in median region. Genitalia. Median lobe (Figs 46, 55) elongated oval; apical process convergent at apex in ventral aspect. Apical lobe of paramerites (Fig. 64) small and globular, with four setae, a- and b-setae longer than c- and d-setae, b-seta longest, c- and d-setae short, subequal in length. Spermatheca (Fig. 73) with bursa large and fusiform; umbilicus absent; duct short, round apically.

Distribution.

Korea (South, North) and Japan.

Remarks.

This species is identified for the first time in South Korea. Most specimens were found on mushrooms in forest.