Laccobius (Microlaccobius) formosus Gentili, 1979

Liu, Hsing-Che & Fikáček, Martin, 2021, Review of the Taiwanese Laccobius Erichson, 1837 (Coleoptera: Hydrophilidae) with description of a new species, Zootaxa 4963 (3), pp. 587-599 : 588-590

publication ID	https://doi.org/ 10.11646/zootaxa.4963.3.11
publication LSID	lsid:zoobank.org:pub:05C2E47F-426D-42EF-B07E-D586C63B6527
DOI	https://doi.org/10.5281/zenodo.4740350
persistent identifier	https://treatment.plazi.org/id/03C29A73-FFC6-4101-FF4B-A69106C5FE71
treatment provided by	Plazi
scientific name	Laccobius (Microlaccobius) formosus Gentili, 1979
status

Treatment

Laccobius (Microlaccobius) formosus Gentili, 1979 View in CoL 台灣flǿ牙ḃ

( Figs 11, 15 View FIGURES 10–18 , 19 View FIGURES 19–22 , 23 View FIGURES 23–26 )

Laccobius (Microlaccobius) formosus Gentili, 1979: 48 View in CoL .

Material examined. TAIWAN: TAITUNG: 1 male, 3 females, ( NMNS): Lanyu [ae嶼], Yonghsing , 17-19.VIII.1998. H.T.Shih & K.W.Huang. L.I.T, [specimens NMNS ENT 3209-1094 View Materials , 3209-1690 View Materials , 3209-1141 View Materials , 3209-1403 View Materials ] ; 1 male, ( NMNS): Donghe [東河], Jindonglai Forest Road, 4.VIII.2012, Y. T. Wang leg , Light . KAOHSIUNG: 1 male, 6 spec., ( NMNS): Liukuei, Shanping [Oi平], 22-23.IV.2004. C.S.Lin & W.T.Yang, UV light trap, [specimens NMNS ENT 4409-723 View Materials , 4409-737 View Materials , 4409-712 View Materials , 4409-919 View Materials , 4409-734 View Materials , 4409-709 View Materials , 4409-711 View Materials ] ; 1 male, ( HCLC): Liouguei District [六 AE區], Laonong River [Ž濃ë], 22.996017°N 120.638178°E, 229m, 24.VI.2020. Hsing-Che Liu & Uitsiann Ong leg. GoogleMaps HSINCHU: 1 male, 1 female, ( HCLC): Hengshan Township [DZ山ė], Youluo Stream [油ǎë], 24.714584°N 121.141335°E, 172 m, 14.II.2019. Hsing-Che Liu leg. GoogleMaps NANTOU: 1 males, 5 spec., ( NMNS): Puli Township [埔¶ D], Meixi [眉ë], 23.988475°N 121.017601°E, 536m, 12.II.2020. Hsing-Che Liu leg. GoogleMaps ; 9 spec., ( NMPC) 4.4 km W of Puli Township start of the Shikeng Road , 530 m 23.988000, 121.017833 15.II.2020. Fikáček, Hu, Liang & Liu lgt. (2020-TW003) GoogleMaps . PINGTUNG: 1 spec., ( TARI): Neipu [內埔], 26.II.2020. Y.-T. Chung leg. ; 1 male, 2 spec., ( HCLC) Ligang Township [¶ffiė], Erchong River [二AEë], 22.7982°N 120.5011°E, 32m, 26.IV.2020. Hsing- Che Liu leg. GoogleMaps TAINAN: 1 male, ( HCLC): Zuozhen District [左D區], Jiaotan [m潭], 23.V.2020. by light trap, Kunta Ho & Wei-Chai Wang leg. TAICHUNG: 8 spec. ( NMPC): Heping distr,, Bashianshan Mts., Dajiaxi River at Songhe village , 24.17996°N 120.98233°E, 665 m, 5.i.2018, stony river partly with gravel banks: in fine gravel below stones and in green algae mats at the side of the river, Fikáček, Liang & Hsiao lgt. (2018-TW01) GoogleMaps ; 1 spec. ( NMPC): Heping distr., Xueshankengxi River E of Taoshan village, 24.32684°N 120.95377°E, 743 m, 6.i.2018, in gravel and among algae at side of a large stony river, Fikáček, Liang, Hsiao lgt. (2018-TW06) GoogleMaps .

Published records. Taihoku [= Taipei] ( Gentili 1979). Chipon [= Taitung County]; Kaohsiung; Heito [= Pintung County]; Hualien; Ilan [= Yilan] ( Gentili 1989, 1995); New Taipei ( Gentili 2003).

Diagnosis. Body size 2.2–2.7 mm, body width 1.6–1.9 mm. Body oval ( Fig. 11 View FIGURES 10–18 ). head black with preocular yellowish spots, Antennae with 8 antennomeres. Pronotum pale, with a large slightly metallic central dark spot ( Fig. 19 View FIGURES 19–22 ). Elytra surface pale, with dense slightly irregular series of dark spots. Male genitalia ( Fig. 15 View FIGURES 10–18 ): Aedeagus 0.7 mm long. Median lobe slender, rounded and membranous at apex; parameres much longer than median lobe, apex widely rounded and membranous, truncate inwards.

Differential diagnosis. Laccobius formosus Gentili, 1979 is very similar to L. fragilis Nakane, 1966 , from which it only differs in the median lobe broadly rounded at apex.

Distribution. China (Gansu, Guandong, Guangxi, Hainan, Hubei, Hunan, Jiangxi, Liaoning, Sichuan, Shaanxi, Shandong), Russia (Far East), Taiwan ( Fig. 27 View FIGURES 27 ) ( Przewoźny 2020, this paper). In Taiwan, L. formosus is distributed throughout the main island.

Bionomics. All specimens were collected from stony streams ( Fig. 23 View FIGURES 23–26 ).