Acrotona (Acrotona) koreana Lee & Ahn 2018, sp. nov.
Creators: name: Lee, Seung-Gyu
name: Ahn, Kee-Jeong
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Staphylinidae
Acrotona
Acrotona koreana

description: Acrotona (Acrotona) koreana Lee & Ahn, sp. nov.
(Figs. 1B, 2 A–F, 3A–H, 4A–H)
Description. Length about 2.0 mm. Body (Fig. 1B) surface fairly glossy and densely pubescent, with fine microsculpture. Body reddish yellow to reddish brown; head almost black; abdominal segments V–VII darker than other parts. Head. Transverse (Fig. 3A), approximately 1.2 times as wide as long, widest across eyes, distinctly narrower than pronotum; eyes very large, about 2.0 times as long as temples; gular sutures moderately separated, diverged basally; cervical carina complete. Antennae (Fig. 3B) long and slender; antennomeres 1–3 elongate, 2 slightly longer than 3, 4–10 subquadrate to transverse, 11 longest, about as long as preceding two combined. Mouthparts. Labrum (Fig. 2A) transverse, slightly emarginate in anterior margin, with ε-sensillum and about nine macrosetae on each side of midline; epipharynx (Fig. 2B) with several sensilla, including two lateral sensory rows on each side of midline; α-sensillum long and setaceous, more than 2.0 times as long as ε-sensillum, β- and γsensilla very short. Mandibles (Figs. 2 C–D) about 1.7 times as long as basal width; right one (Fig. 2C) with small internal tooth; prostheca composed of three portions, second portion longer. Galea and lacinia of maxilla (Fig. 2E) long and slender; lacinia composed of seven spines in distal comb region, two isolated spines present; maxillary palpomere 2 about 2.6–2.8 times as long as wide, 3 about 2.3–2.5 times as long as wide, 4 digitiform, filamentous sensilla not reaching to basal half. Labium (Fig. 2F) with ligula long and slender, divided into two lobes in basal half; prementum with two medial setae narrowly separated; two basal pores close together, about 1.0 times width of basal pore; medial pseudopores absent; several lateral pseudopores, 1 setal pore and 2 real pores present on each side of midline; labial palpomere 1 about 1.3–1.5 times as long as wide, γ-setula contiguous with f-seta, 2 shortest, about 1.2–1.3 times as long as wide, 3 parallel-sided and about as long as 1, about 3.0–3.5 times as long as wide. Mentum (Fig. 2F) trapezoidal, anterior margin emarginate; v-seta very long, slightly closer to u-seta than w-seta. Thorax. Pronotum (Fig. 3C) approximately 1.4 times as wide as long, widest at basal third to half; pubescence directed posteriorly in midline. Metanotal scutum (Fig. 3E) with one long seta and about one to four short setae on each side of midline. Mesocoxal cavities narrowly separated; mesoventral process (Fig. 3F) slightly pointed at apex, distinctly longer than isthmus and metaventral process combined. Elytra longer and slightly wider than pronotum; elytron (Fig. 3H) approximately 1.4–1.5 times as long as wide, postero-lateral margin sinuate; pubescence directed posterior and postero-laterally; hind wings fully developed, flabellum (Fig. 3E) composed of about six long 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 19:24:22:52 (protarsus); 27:28:29:27:50 (mesotarsus); 34:36:35:33:60 (metatarsus); one empodial seta present, shorter than claw. Abdomen. Widest in segments III–IV; surface fairly glossy and densely pubescent, fine and transverse microsculpture; conspicuous macrosetae present in lateral regions; macrochaetal arrangement of tergites II–VI 01-02-12-13-13; tergite VII subquadrate; male tergite VIII (Fig. 4A) with four macrosetae on each side of midline, posterior margin truncate; male sternite VIII (Fig. 4B) with seven macrosetae on each side of midline, posterior margin slightly convex; posterior margin of female tergite VIII (Fig. 4C) similar to male’s; female sternite VIII (Fig. 4D) with six macrosetae on each side of midline, posterior margin broadly round, with long marginal setae and in median region. Aedeagus. Median lobe (Figs. 4 E–F) narrowly ovate and widest in basal fourth, narrow apically and blunt at apex in ventral aspect; apical process elongate and almost straight in lateral aspect. Apical lobe of paramerites (Fig. 4G) elongate and parallel-sided, with four setae; a-seta slightly longer than other setae positioned apically; b- and d-setae subequal in length; c-seta slightly shorter. Spermatheca. Bursa round, without umbilicus; duct relatively slender, coiled and twisted at apex (Fig. 4H).
Type material. Holotype, labeled as follows: ‘ KOREA: Chungnam Prov., Daejeon-si, Seo-gu, Jangan-dong, Mt. Jangtaesan, N36°13'01.0" E127°20'34.6" 222 m, 29 V 2014, SG Lee, JS Lee, leaf litter’. Paratypes, 6 exx. (two on slide), same data as holotype.
Distribution. Korea (South).
Remarks. This species is similar to A. lutulenata (Sharp), but can be distinguished by the characters provided in the key and different shape and structure of the aedeagus and spermatheca.
description: Published as part of Lee, Seung-Gyu & Ahn, Kee-Jeong, 2018, A taxonomic review of Korean Acrotona Thomson with a description of new species (Coleoptera, Staphylinidae, Aleocharinae), pp. 247-263 in Zootaxa 4418 (3) on pages 251-253, DOI: 10.11646/zootaxa.4418.3.3, http://zenodo.org/record/3769610