Acrotona (Acrotona) pseudotenera ( Cameron, 1933 )

Lee, Seung-Gyu & Ahn, Kee-Jeong, 2018, A taxonomic review of Korean Acrotona Thomson with a description of new species (Coleoptera, Staphylinidae, Aleocharinae), Zootaxa 4418 (3), pp. 247-263 : 256-258

Acrotona (Acrotona) pseudotenera ( Cameron, 1933)

( Figs. 1D , 6 A–J)

Atheta (Coprothassa) pseudotenera Cameron, 1933: 215 .

Ischnopoda (s. str.) uncinata Sawada, 1971: 80 .

Acrotona rassii Muona, 1993: 9 .

Acrotona paeksongricus Paśnik, 2001: 205 ; Smetana, 2004: 364; Schülke & Smetana, 2015: 508; Ahn et al., 2017: 292. new synonym.

Acrotona pseudotenera: Smetana, 2004: 365 ; Shibata et al., 2013: 106.

Acrotona (Acrotona) pseudotenera: Schülke & Smetana, 2015: 509 .

Description. Length 2.3–2.7 mm. Body ( Fig. 1D ) surface glossy and densely pubescent, with microsculpture. Body dark brown to black; elytra and legs paler than other parts. Head. Subcircular, approximately 1.0–1.1 times as wide as long, widest across eyes, distinctly narrower than pronotum; eyes slightly large and prominent, about 1.2– 1.3 times as long as temples; gular sutures moderately separated, diverged basally; cervical carina complete. Antennae ( Fig. 6A ) long and slender; antennomeres compactly close together, 1–3 elongate, 2 slightly longer than 3, 4–10 subquadrate to slightly transverse, 11 longest, about as long as preceding two combined. Mouthparts. Labrum transverse, slightly emarginate in anterior margin, with ε-sensillum and about eight macrosetae on each side of midline; epipharynx with several sensilla, including two lateral sensory rows on each side of midline; αsensillum long and setaceous, about 2.0 times as long as ε-sensillum, β- and γ-sensilla very short. Mandibles about 1.5 times as long as basal width; right one with small internal tooth, internal margin slightly serrulate; prostheca composed of three portions, second portion longer. Galea and lacinia of maxilla moderately long and slender; lacinia of maxilla with seven short spines in distal comb region, two isolated spines present; maxillary palpomere 2 about 2.8–3.0 times as long as wide, 3 about 2.5–2.7 times as long as wide, 4 digitiform, filamentous sensilla reaching to basal half. Labium with ligula divided into two lobes in basal half; prementum with two medial setae more or less widely separated; two basal pores widely separated, more than 5.0 times width of basal pore; several medial pseudopores, lateral pseudopores and 1 setal pore and 1 real pore present on each side of midline; labial palpomere 1 about 1.8–2.0 times as long as wide, γ-setula contiguous with b-seta, 2 shortest, about 1.2–1.4 times as long as wide, 3 more or less dilated apically and slightly shorter than 1, about 3.0 times as long as wide. Mentum trapezoidal, anterior margin slightly emarginate; v-seta relatively short, closer to u-seta than w-seta. Thorax. Pronotum approximately 1.4–1.5 times as wide as long, widest in basal third to half; pubescence directed posteriorly in midline. Metanotal scutum with one long seta and about three to six relatively short setae on each side of midline. Mesocoxal cavities narrowly separated, mesoventral process blunt at apex, distinctly longer than isthmus and metaventral process combined; length ratio of mesoventral process, isthmus and metaventral process 20:5:3. Elytra transverse, slightly wider than pronotum; elytron 1.3–1.4 times as long as wide, pubescence directed posteriorly and postero-laterally; postero-lateral margin slightly sinuate; hind wings fully developed, flabellum composed of about six to eight setose lobes. Legs. Slender and long, with pubescence and macrosetae; meso- and metatibiae with different length of two spurs at apex; length ratio of tarsomeres 32:39:36:72 (protarsus); 34:53:49:42:70 (mesotarsus); 68:68:64:53:90 (metatarsus); one empodial seta present, shorter than claw. Abdomen. Widest in segments III–IV; surface glossy and densely pubescent, with imbricate microsculpture; macrochaetal arrangement of tergites II–VI 01-03 (or 13)-13-13-13; male tergite VIII ( Fig. 6B ) with four macrosetae on each side of midline, posterior margin truncate; male sternite VIII ( Fig. 6C ) with seven macrosetae on each side of midline, posterior margin round, with inconspicuous marginal setae; posterior margin of female tergite VIII ( Fig. 6D ) similar to male’s; female sternite VIII ( Fig. 6E ) with four macrosetae on each side of midline, posterior margin broadly round, with long marginal setae, minute setae present in median region. Aedeagus. Median lobe ( Figs. 6 F– H) elongate, widest in basal third to fourth, apical process elongate and subparallel-sided, blunt at apex in ventral aspect. Apical lobe of paramerites ( Fig. 6I ) pointed apically, with four setae; a-seta longest and positioned basally, b- and d-setae relatively long and subequal in length, d-seta shortest and close to d-seta. Spermatheca. Bursa with relatively large umbilicus; duct slightly coiled ( Fig. 6J ).

Type material. Holotype, ♂, labeled as follows: ‘ Holotype, JAPAN Kobe, Hanada 19·XII·32 J.E.A. Lewis, M. Cameron. Bequest. B. M. 1955–147., Atheta pseudotenera Cam. P.M. Hammond det. 1973 HOLOTYPE, a. pseudotenera Cam TYPE , Holotype Atheta pseudotenera Cameron, 1933 det. Maruyama, 2011’. Holotype, ♂, labeled as follows: ‘Korea 1981 Pekson-ri A. Szeptycki; HOLOTYPE Acrotona paeksongricus sp. n. det. G. Paśnik 2000’ [ North Korea , Pyeongannam Prov. , Pyeongseong-si, Baeksong-ri, 1981, A. Szeptycki] .

Material examined. SOUTH KOREA: Chungnam Prov.: 1 ex., Dangjin-gun, Hapdeok-myeon, Soso-ri , N36°49′06.3″ E126°45′43.6”, 7 vi 2006, SJ Park, DH Lee, Sifting ; 3 exx., Dangjin-gun , Sinpyeong-myeon , Maesan-ri , 30 vi 2006, N36°54′07.7″ E126°48′25.4″ 36 m, SJ Park, YH Lim, HW Kim, decaying vegetable . Gangwon Prov.: 1♀, Pyeongchang-gun, Bangnim-myeon, Ungyo 2-ri, Mt. Baekdeoksan , 12 vii–16 vii 2001, KJ Ahn, SJ Park, CW Shin, FIT ; Gyeongnam Prov.: 1♂, Sacheon-si, Jeongdong-myeon, Sucheong-ri , 10 vi 1986, GS Lee . Jeonnam Prov.: 1 ex., Jangseong-gun, Jangseong-eup, Yutang-ri , N35°18′54.8″ E126°48′34.0″ 90 m, 22 v 2007, TK Kim, YH Kim, dung .

Distribution. Korea (South, North), Japan and Europe.

Remarks. This species was first recorded in North Korea by Paśnik (2001) and is recorded here for the first time in South Korea. After comparative study of the syntype of Acrotona pseudotenera (Cameron) and the holotype of Acrotona paeksongricus Paśnik , we conclude that the differences between these two species are insufficient to separate them as different species. A new synonym, A. paeksongricus under A. pseudotenera , is proposed in this study.

Figures

FIGURE 1. Habitus. A, Acrotona (Acrotona) aterrima; B, A. (A.) koreana sp. nov.; C, A. (A.) lutulenta; D, A. (A.) pseudotenera; E, A. (A.) setaria; F, A. (A.) suspiciosa suspiciosa; G, A. (A.) vicaria.

FIGURE 6. Acrotona (Acrotona) pseudotenera. A, antenna; B, male abdominal tergite VIII (dorsal aspect); C, male abdominal sternite VIII (ventral aspect); D, female abdominal tergite VIII (dorsal aspect); E, female abdominal sternite VIII (ventral aspect); F, median lobe of aedeagus (lateral aspect, everted internal sac); G, median lobe of aedegus (lateral aspect, not everted internal sac); H, median lobe of aedeagus (ventral aspect); I, paramere (lateral aspect); J, spermatheca. Scales = 0.1 mm.