Review of the Taiwanese Laccobius Erichson, 1837 (Coleoptera: Hydrophilidae) with description of a new species Author Liu, Hsing-Che Taiwanese Society of Insect Natural History, No. 8, Wufeng Rd., Hsinchu County 310, Taiwan. Author Fikáček, Martin 0000-0002-2078-6798 Department of Biological Sciences, National Sun Yat-sen University, No. 70 Lien-hai Rd., Kaohsiung City 80424, Taiwan. & Department of Entomology, National Museum, Cirkusová 1740, CZ- 19100 Praha 9 - Horní Počernice, Czech Republic. & Department of Zoology, Faculty of Science, Charles University, Viničná 7, CZ- 12844 Praha 2, Czech Republic. mfikacek @ gmail. com; https: // orcid. org / 0000 - 0002 - 2078 - 6798 mfikacek@gmail.com text Zootaxa 2021 2021-04-20 4963 3 587 599 journal article 7088 10.11646/zootaxa.4963.3.11 37bbbcdd-7455-4fd2-854c-49f010b3b27c 1175-5326 4704278 05C2E47F-426D-42EF-B07E-D586C63B6527 Laccobius ( Glyptolaccobius ) politus Gentili, 1979 光澤flǿ牙ḃ ( Figs 10, 14 , 26 ) Laccobius ( Microlaccobius ) politus Gentili, 1979: 46 . Laccobius (Cyclolaccobius) politus : Gentili (1995: 257) ; Gentili (2003: 414) ; Hansen (1999: 132) . Oocyclus flaveolus Hebauer & Wang, 1998: 41 . Synonymized with L. politus by Gentili (2012) . Laccobius ( Glyptolaccobius ) politus : Jia et al (2019: 72) . Material examined. TAIWAN : NANTOU : 7 spec. , ( NMPC ): 5.5 km SSW of Heshe at Rd. 07 23.55263°N 120.86947°E , 1070m . 16.V.2018 . Fikáček , Liang , Liu & Minoshima. (2018-TW37) ; 15 spec. , ( NMPC ): wet concrete wall at Kaigao Rd. 4.25 km SE of Heshe ; 23.5641°N 120.91837°E . 15.V.2018 . Fikáček , Liang , Liu & Minoshima. (2018-TW34) ; CHIAYI : 1 spec. , ( NMPC ): track down to Yuntan waterfall 3.5 km W of Meishan township 23.5327417 , 120.6557500 ; 850m 1.v.2019 ; Damaška , Fikáček , Liu & Tkoč lgt. (2019-TW13) . NEw TAIPEI : 1 male , 3 spec. ( HCLC , NCHU ): Pingxi District , Wanggu Waterfall [ 望古瀑布 ], 30.III.2020 . on the wet rock, Hsing-Che Liu leg. HSINCHU : 2 males , 5 spec. , ( HCLC ): Emei Township [ 峨眉ė ], Qixing Village [ 七ffl村 ], 24.656664°N 121.023909°E , 151m , 24.VIII.2020 . on wet rock, Hsing-Che Liu leg. TAICHUNG : Heping distr, Bashianshan Mts. , beginning of Bashianshan Forest Rd. , 5.i.2018 24.19808°N 121.00115°E , 722 m , exposed wet concrete/stony wall at side of the road, Fikáček , Liang , Hsiao (2018-TW03) . Published records: New Taipei ( Gentili 1979 , 2003 ; Hebauer & Wang 1998 ); Hualien ( Gentili 1995 ); Keelung , Kaohsiung ( Hebauer & Wang 1998 ); Nantou ( Gentili 2003 , 2012 ). Diagnosis. Body length 1.8–2.0 mm, maximum body width 1.2–1.3 mm . Body oval ( Fig. 10 ), strongly convex. Dorsal back, pronotum and elytra with lateral dark brown margin. Surface of pronotum and elytra with sparse white setae. Legs brown. Male genitalia ( Fig. 14 ): Aedeagus 0.5 mm long. Median lobe slender, wide basally, slightly narrowing towards midlength, apical rounded; parameres slightly shorter than median lobe or as long as median lobe, weakly narrowing at apex, narrowing towards basal, basal truncate. Differential diagnosis. Laccobius politus is similar to Chinese species of L. hainanensis Jia, Gentili & Fikáček, 2013 , L. martini Jia, Song & Gentili, 2013 and L. motuoensis Jia, Chen & Fikáček, 2019 . It can be differentiated from them by the dorsal surface with sparse white setae, median lobe indistinctly constricted subapically, and parameres narrower than median lobe, rounded apically. This species is the only inhabitant of wet rocks in Taiwan , as well as that only representative of the subgenus Glyptolaccobius in Taiwan . Therefore, this species can be easily distinguished from other Taiwanese species. Distribution. China ( Yunnan ), Nepal , Taiwan ( Fig. 27 ) ( Gentili 1979 ; Gentili 2003 ; Hebauer 2006 ; Jia et al . 2013, this paper). Bionomics. All examined specimens were collected on wet rocks ( Fig. 26 ).