Laccobius (Microlaccobius) formosus Gentili, 1979

Jia, Fenglong, Gentili, Elio & Fikáček, Martin, 2013, The genus Laccobius in China: new species and new records (Coleoptera: Hydrophilidae), Zootaxa 3635 (4), pp. 402-418 : 413-416

Laccobius (Microlaccobius) formosus Gentili, 1979

( Fig. 19 )

Material examined. Guangdong: 1 male, 1 female (SYSU): Xinyi, 17.vi.1960, Zhelong Pu lgt.; 2 males, 2 females (SYSU): Guangzhou, without additional data; 1 male (SYSU): Fengkai, Heishiding, 20–22.vii.2007, Fenglong Jia lgt. Guangxi: 1 male, 2 females (SYSU): Hechi, 4.xi.1941, Zhelong Pu lgt.; 1 male (SYSU): Yangshuo, 1985, Shoujian Chen lgt. Hainan: 1 female (SYSU): Jianfengling Mts., Tianchi, 11.xi.1983, Zhihe Huang lgt. Hubei: 1 male, 1 female (SYSU): Zigui, Jiutouling, 110 m a.s.l., at light, 5.ix.1994, Fasheng Li lgt.; 2 males, 5 females (NMPC, MSNV): Wutienshan Mts., Yingshan, 5.v.2005, V. Ryjáček lgt. Hunan: 17 males, 17 females (SYSU): Nanyue, Hengshan Mt., 4.ix.1941, Zhelong Pu lgt.; 1 male, 1 female (SYSU): Yizhang, 10–11.ii.1941, Zhelong Pu lgt.; 7 males, 4 females (SYSU): Liyuan, 6.iii.1941, Zhelong Pu lgt.; 1 female (SYSU): Huaihua, Yushuwan, 17.vi.1965, Zhenyao Chen lgt. Jiangxi: 2 males, 2 females (SYSU): Shangrao, Sanqingshan, 15–20.iv.2007, Fenglong Jia lgt.; 4 males, 2 females (SYSU): Jinggangshan Mts., Xiangzhou, 26°35.5ʹN 114°16.0ʹE, 374 m a.s.l., 26.iv.2011, Fenglong Jia & Shuang Zhao lgt.; 1 male, 1 female (NMPC): same locality and date, at light on the bridge above the slowly flowing stony river, M. Fikáček & J. Hájek lgt.; 2 males, 3 females (SYSU): Jinggangshan, Xiangzhou, 2.vii.2011, Weicai Xie, Jinwei Li & Lijun Yang lgt.; 2 males, 2 females (SYSU): Jinggangshan Mts., Baiyinhu, 800 m, 27.iv.2011, Fenglong Jia & Shuang Zhao lgt. Shaanxi: 2 males, 4 females (SYSU): Zhashui, 31.vii.2001, Ling Zhao lgt.

Comments. Widely distributed species reaching from Russian Far East through whole China to Southeast Asia ( Thailand, Vietnam). New for Guangdong, Guangxi, Hainan, Hubei, Hunan, Jiangxi provinces. Laccobius formosus resembles L. fragilis Nakane, 1966 by the morphology of the aedeagus (the latter occurring in Japan, Korea and northern China). However, L. formosus differs from L. fragilis by the following characters: (1) head and pronotum bears very weak shagreen (in contrast, a distinct shagreen consisting of micropunctures is developed on the head and pronotum of L. fragilis ); (2) primary and secondary rows of elytra are rather similar to each other in size of punctures (they differ in size of punctures in L. fragilis ); (3) apex of the median lobe is rounded apically (acute in L. fragilis ); and (4) parameres partly sclerotized and hence regularly expanded at apex (apex of parameres membranous and hence irregularly expanded in L. fragilis ). The aedeagus of a Chinese specimen of L. formosus is illustrated in Fig. 19 .

Laccobius (Microlaccobius) hammondi Gentili, 1984 ( Figs. 20–25 )

Material examined. Beijing: Shisanling, 10.viii.1962, Zhelong Pu lgt., with a label “ Laccobius gracilis, Peiping ”; 1 male (IRSNB): Peping [= Beijing], 33 / Collector C.F. Wu // A. d’Orchymont det. Lacc. gracilis var. sculpt . Mots.. Guangdong: 1 male, 1 female (SYSU): Danxiashan Mt., 20.iv.2008, Fenglong Jia lgt.; 3 males, 6 females (SYSU): Lianzhou (Lianxian), Dadongshan, 27.ix.2008, Yun Wang lgt.; 2 males, 2 females (SYSU): Nanling, Dadongshan, 22.vi.2009, Fenglong Jia lgt.; 1 male, 1 female (SYSU): Lianxian (Lianzhou), Dadongshan, 7.ix.1992, Fenglong Jia & Ru Dai lgt.; 5 males, 3 females (SYSU): Guangzhou, Baiyunshan, 18–20.iv.1958, Zhelong Pu lgt.; 2 males, 2 females (SYSU): Xingning, Luofu, Huangmaozhang, 2.vii.2004, Fenglong Jia lgt. Guangxi: 5 males, 5 females (SYSU): Hechi, 4.xi.1941, Zhelong Pu lgt. Guizhou: 3 males, 4 females (SYSU): Rongxian County, Pingyang, Xiaodanjiang River, 685 m a.s.l., 15.ix.2005, Shuang Zhao lgt. Hunan: 1 male, 3 females (NHMW): ca. 25 km N Pingjang City, 113°38ʹ0 5ʺE 28°50ʹ10ʺN, ca. 200 m a.s.l., 20.iii.2003, Schönmann, Komarek & Wang lgt. (CWBS 500); 2 males, 2 females (SYSU): Nanyue (Hengshan Mt.), 2.ix.1941, Zhelong Pu lgt.; 1 female (SYSU): Huaihua, Yushuwan, 17.vi.1965, Zhenyao Chen lgt. Jiangxi: 65 males, 55 females (SYSU): Shangrao, Sanqingshan, 15–20.iv.2007, Fenglong Jia lgt.; 20 spec. (SYSU, MSNV), Jinggangshan Mts., Xiangzhou, 26.iv.2011, Shuang Zhao & Fenglong Jia lgt.; 12 spec. (NMPC, MSNV, SYSU): Jinggangshan Mts., Xiangzhou (forested valley south of the village), 26°35.5ʹN 114°16.0ʹE, 374 m a.s.l., under stones and among sand at the bank of a stony river below the bridge, 26.iv.2011, Fikáček & Hájek lgt.; 1 female (NMPC): same locality and date, rice field and exposed stream directly in the village; 5 spec. (NMPC): same locality and date, at light on the bridge above the slowly running stony river, 17 spec. (NMPC, MSNV): Jinggangshan Mts., Baiyinhu env., 26°36.8ʹN 114°11.1ʹE, 800 m a.s.l., drying-up stream in the stony bed, night collecting in isolated pools in the stream, on the wet rocks with algae, 23–29.iv.2011, Fikáček, Hájek & Kubeček lgt. Shaanxi: 41 spec. (SYSU, MSNV): Xi’an, Dayu, 12.v.2011, Fenglong Jia lgt.; 3 males, 7 females (NMPC, MSNV): Dayu village, Chanhe river ca. 30 km SSE of Xian, 34°01.0ʹN 109°06.9ʹE, 720 m a.s.l., 11.v.2011, M. Balke & J. Hájek lgt.; 1 male (SYSU): Chang’an, Nanwutai, 23.viii.1984, Zhihe Huang lgt. Sichuan: 3 males, 2 females (SYSU): Qingchengshan, 8.viii.1982, Zhihe Huang lgt.

Comments. New for Beijing, Guangxi, and Jiangxi. Laccobius hammondi Gentili is a very common species in China and is very close to L. oscillans Sharp. It may be separated from the latter by the aedeagus, having the median lobe more dilated at the apical third than L. oscillans (compare Figs. 25 and 26 ). Another distinctive character seems to be the pronotal surface, which is strongly shagreened in L. oscillans .

The examined male specimen from Beijing has the aedeagus identical to the specimens from Shaanxi and Jiangxi. Reexamination of the specimens from the Jilin province published as L. oscillans by Gentili (1995) shows that the specimens are actually more similar to L. hammondi than to L. oscillans in the above characters. These data suggest that the previous records of L. oscillans from Beijing, northern China and possibly even Russian Far East may refer to L. hammondi . A revision of the specimens from continental Asia as well as from southern Japan is necessary to understand the real distribution of both L. oscillans and L. hammondi .

The aedeagus of Laccobius (M.) yonanguniensis Matsui, 1993 from the Ryukyu Islands seems to be extremelly similar to that of L. hammondi based on the drawing published by Matsui (1993). Laccobius yonanguniensis is most likely a junior synonym of L. hammondi but we were not able to examine the types of the former species. For that reason, we refrain from establishing this synonymy here.

Laccobius (Microlaccobius) himalayanus Gentili, 1988

Material examined. Yunnan: 1 male (ASHC): Xishuang-banna, 20 km NW Jinghong, Man Dian, 22°07ʹN 100°40ʹE, 730 m a.s.l., 26.v.2008, A Weigel lgt.

Comments. Reaching from Nepal and northwestern India (West Bengal, Meghalaya) to SE Asia ( Laos, Vietnam) and Yunnan.

Figures

FIGURES 17 – 19. Aedeagi, dorsal views. 17: Laccobius hingstoni. 18: L. inopinus. 19: L. formosus.

FIGURES 20 – 26. Laccobius hammondi (20 – 25) and L. oscillans (26). 20 – 21: general habitus (20: dorsal view, 21: lateral view). 22 – 24: aedegus of L. hammondi (22: dorsal view, 23: lateral view, 24 ventral view). 25 – 26: aedeagus with open parameres showing the shape of the median lobe (25: L. hammondi, 26: L. oscillans from Japan, Sapporo env., Kimotetsu).