Helochares pallens ( MacLeay, 1825 ), 1935

Jia, Fenglong & Tang, Yu-dan, 2018, A revision of the Chinese Helochares (s. str.) Mulsant, 1844 (Coleoptera, Hydrophilidae), European Journal of Taxonomy 438, pp. 1-27 : 15-20

Helochares pallens ( MacLeay, 1825)

Figs 32–42 , 52

Enhydrus pallens MacLeay, 1825: 35 .

Helochares parvulus Reiche & Saulcy in Reiche, 1854: 9 .

Helochares lewisius Sharp, 1873: 60 .

Helochares dispar Sharp, 1903: 7 .

Helochares laeviusculus Régimbart, 1906: 261 .

Helochares parvulus – Reiche & Saulcy 1856: 359.

Philhydrus pallens – Gemminger & Harold 1868: 482.

Philhydrus parvulus – Gemminger & Harold 1868: 482.

Helochares (s. str.) lewisianus – Zaitzev 1908: 382 (misspelling).

Enochrus (Methydrus) parvulus – Zaitzev 1908: 384.

Enochrus (Lumetus) pallens – Zaitzev 1908: 388.

Helochares (s. str.) pallens – d’Orchymont 1926: 232.

Helochares (s. str.) pallens ssp. laeviusculus – Balfour-Browne 1950: 60.

Diagnosis

Length 2.8–3.4 mm. Yellowish brown with labrum and frons dark ( Fig. 32 ). Dorsum with finer punctures ( Fig. 36 ). Systematic punctures on clypeus slightly stronger than ground punctures. Clypeus never impressed in front of eyes, lateral margin distinctly narrowed anteriorly ( Figs 35–36 ). Maxillary palps yellowish brown, ca 1.2× as long as width of head. Antennae with pedicel slightly shorter than antennomeres 3–6 combined. Mentum slightly impressed anteromedially, never with wrinkles ( Fig. 37 ). Submentum with somewhat even, dense, coarse and strong punctures. Usually eight to nine striae on underside of elytra visible from dorsal side ( Figs 32 , 41–42 ). Mesoventrite without a low transverse ridge medially ( Fig. 39 ). Metaventrite without glabrous area medially. Femora densely pubescent except apical eighth. Apex of parameres not dilated inwards, somewhat narrowly rounded near apex. Membranous inner sac with several small dentiform bulges on each side. Median lobe with sharp apex ( Fig. 52 ).

Material examined

CHINA: Guangdong: 3 ♂♂, 2 ♀♀, 28 spec., Xuwen, 27 Apr. 1985, Zhihe Huang leg.; 2 ♂♂, 4 ♀♀, 34 spec., Lianjiang, 25 Apr. 1985, Wu Wu leg.; 2 ♀♀, Lianjiang, Shiling, 12 Apr. 1985, Zhihe Huang leg.; 1 ♀, Shiling, 12 Apr. 1985, Wu Wu leg.; 1 ♂, Lianjiang, Shiling, 24 Apr. 1985, Wu Wu leg.; 3 spec., Guangzhou, Aug. 1938, Zhelong Pu leg.; 12 spec., Guangzhou, Henan, 24 May 1957, Zhelong Pu leg.; 2 spec., Guangzhou, Henan, 1 Mar. 1958, Zhelong Pu leg.; 9 spec., “Hainan”, 17 Jul. 1957, Zhelong Pu leg.; 4 spec., “Hainan”, 16 Jul. 1957, Cuiying Li leg.; 2 spec., “Hainan”, 17 Jul. 1957, Cuiying Li leg.; 6 spec., Yingde, 5 Aug. 1962, Ping Lin leg.; 3 spec., Lechang, 12 Aug. 1962, Ping Lin leg.; 34 spec., Xinhui, Aug. 2001, Xiaoli Tong leg.; 8 spec., Xingning, Luofu Mount, Huangmao peak, 1 Jul. 2004, Fenglong Jia leg.; 2 spec., Xingning, Luofu Mount, Tieshan, 1 Jul. 2004, Fenglong Jia leg.; 6 spec., Lianzhou, Dadong Mount, 25–28 Jul. 2008, Yun Wang leg.; 16 spec., Fengkai, Heishiding, 3 Jun. 2001, light trap, Fenglong Jia leg.; 3 spec., Fengkai, Heishiding, 20–22 Apr. 2014, Fenglong Jia, Renchao Lin and Yudan Tang leg.; 3 spec., Fengkai, Heishiding, 2 Jul. 2011, Lijun Yang leg.; 2 spec., Fengkai, Heishiding, 10 Apr. 1985, Wu Wu leg.; 3 spec., Fengkai, He’erkou, 3 Jul. 2011, Lifeng Yang leg.; 2 spec., Fengkai, He’erkou town, 55 m a.s.l., 22 Apr. 2014, Fenglong Jia, Renchao Lin and Yudan Tang leg.; 8 spec., Guangzhou, Shuzhugang, 3 May 1957, Zhelong Pu leg.; 3 spec., Heshan, 18 Mar. 1994, Fenglong Jia leg.; 9 spec., Shipai, 5 Aug. 1956, Zhelong Pu leg.; 16 spec., Huaxian, Dapuling, 26 Aug. 1983, Zhihe Huang leg.; 2 spec., Raoping, summer of 1961; 46 spec., Danxia Mount, nursery, 8 Jun. 2012, Fenglong Jia leg.; 1 spec., Danxia, Yangyuan Mount, Huiyuan pool, 8 Jun. 2012, Fenglong Jia leg.; 5 spec., Danxia Mount, paddy field in the north of Yangyuanshi, 23 Apr. 2012, Fenglong Jia and Junlei Liao leg.; 1 spec., Danxia Mount, 23–26 Apr. 2013, Fenglong Jia leg.; 13 spec., Zhuhai, 24 Jun. 2011, Fenglong Jia leg.; 4 spec., Zhuhai, mountain behind campus of Sun Yat-sen University, 5–8 Jul. 2011, Fenglong Jia leg.; 6 spec., Zhuhai, Hengqing Island, 10 Jul. 2006, Fenglong Jia leg.; 6 spec., Zhuhai, Qi’ao Island, 13–15 Jul. 2005, Fenglong Jia leg.; 16 spec., Gaoming, Yangmei town, 23–26 Apr. 2006, Fenglong Jia leg.; 18 spec., Guangzhou, Lianhe, 18 May 1964, Jincai Bao and Zhenyao Chen leg.; 24 spec., Guangzhou, Baiyun Mount, 2 Jun. 1964, Jincai Bao leg.; 27 spec., Guangzhou, Xinshi, 11 May 1964, Chengmu Chen and Zhengwei Huang leg.; 19 spec., Guangzhou, Luhu Lake, 2 Jun. 1964, Zhenyao Chen leg.; 6 spec., Guangzhou, Shipai, 8 May 1964, Zhaojian Liang leg.; 2 spec., Guangzhou, Chisha, 28 Apr. 1964, Zhenyao Chen leg.; 6 spec., Heyuan, Wanlu Pool, 15–17 Aug. 2005, Shuang Zhao leg.; 5 spec., Ruyuan, Longxi, 9 May 1964, Zhenyao Chen leg.; 1 spec., Guangzhou, campus of Sun Yat-sen University, 16 May 1964, Jincai Bao leg.; 1 ♀, Guangzhou, campus of Sun Yat-sen University, Jul. 1985; 1 spec., Guangzhou, Sun Yat-sen University, 20 Jun. 1958; 1 ♂, Sihui, Dasha, 6 Mar. 1988, Fenglong Jia leg.; 7 spec., Shenzhen, Futian Mangrove, salt-water fish pond, 30 May–1 Jun. 2015, Fenglong Jia and Renchao Lin leg.; 2 ♂♂, 2 ♀♀, 17 spec., Shenzhen, Futian Mangrove, 2–4 Apr. 2015, Fenglong Jia, Renchao Lin, Zhenhua Liu and Kai Chen leg.; 6 spec., Shenzhen, Yapai Mount, 17 May 2012, Fenglong Jia and Junlei Liao leg.; 1 spec., Shenzhen, Nan’ao, 26 May 2011, Xiaodong Wang and Junlei Liao leg.; 1 ♀, Shenzhen, Haifeng Reservoir, 8–11Aug. 2006, Fenglong Jia leg.; 1 spec., Shenzhen, Qiniang Mount, 7 Jun. 2010, Fenglong Jia leg.; 3 spec., Shenzhen, Longgang, 23–25 May 2011, Fenglong Jia leg.; 1 spec., Shenzhen, Neilingding, 3 Jul. 1998, Haidong Chen leg.; 4 spec., Zhanjiang, Chikan, 25 Apr. 1985, Zhihe Huang leg.; 2 ♂♂, Lian County, Dadong Mount, 16 Apr. 1993, Fenglong Jia leg.; 2 spec., Dinghu Mount, 17 Jul. 1964, Tongxu Peng leg.; 5 spec., Puning, 3 Jan. 1959, Zhelong Pu leg.; 6 spec., Puning, autumn 1958, Zhelong Pu leg.; 2 spec., Guangzhou, Kangle village, Apr. 1957, Ping Lin leg.; 1 spec., Shantou, 15 May 1964, Tongxu Peng leg.; 1 spec., Nanxiong, summer 1942, Zhelong Pu leg.; 1 spec., Dong town, 7 Jul. 1960, Zhelong Pu leg.; 1 spec., Xinyi, 7 Jun. 1960, Zhelong Pu leg.; 1 spec., Lian town, Jun. 1945, Zhelong Pu leg.; 1 spec., Qujiang, Guitou, autumn 1942, Mengyi Mo leg. – Yunnan: 3 ♂♂, 2 ♀♀, 45 spec., Yingjiang, 850 m a.s.l., 25 May 1983, Lizhong Hua leg.; 2 ♂♂, 5 ♀♀, 75 spec., Huijiang, 30 Apr. 1939, Zhelong Pu leg.; 11 spec., Chenggong, 24 Apr. 1940; 80 spec., Pohui, 2 Apr. 1939, Zhelong Pu leg.; 1 spec., Jinning, 24 Apr. 1940, Zhelong Pu leg.; 8 spec., Kunming, 28 May 1939, Zhelong Pu leg.; 8 spec., Lufeng village, 26 Mar. 1940, Zhelong Pu leg.; 2 spec., Lufeng village, 25 Jul. 1939, Zhelong Pu leg.; 3 spec., Pingyi, 1 May 1940, Zhelong Pu leg.; 1 spec., Nujiang Valley, 800 m a.s.l., 9 May 1955; 1 spec., Jinping, Mengla, 370 m a.s.l., 30 Apr. 1956, Renke Huang leg. – Chongqing: 2 ♂♂, 3 ♀♀, 52 spec., 8 Mar. 1942, Xiangzhi Chen leg.; 1 spec., 3 Mar. 1940, Zhelong Pu leg. – Sichuan: 2 spec., E’mei, 1 Aug. 1982, Zhihe Huang leg.; 1 spec., Fujiang, Qiongjiang County, Meihe village, 16 Aug. 1957, Wenyi Pei leg. – Hubei: 3 ♂♂, 3 ♀♀, 77 spec., Dabie Mountain range, Qingtaiguan, 31°12.2′ N, 115°42.1′ E, 1–4 Jul. 2014, Zhenhua Liu leg.; 2 spec., Dabie Mountain range, Wujia Mountain, 31°7.6′ N, 115°45.1′ E, 29 Jun. 2014, light trap, Zhenhua Liu leg.; 4 spec., Wuchang, 17–19 May 1961, Zhelong Pu leg.; 1 spec., Wuchang, 19 May 1961, Zhelong Pu leg.; 1 spec., Zigui, Jiulingtou, 110 m a.s.l., 6 Apr. 1994, Fasheng Li leg. – Hunan: 1 ♂, 2 ♀♀, Huaihua, 15 Aug. 1982, Zhihe Huang leg.; 5 spec., Huaihua, 17 Aug. 1982, Zhihe Huang leg.; 11 spec., Tongdao, 19 Aug. 1982, Zhihe Huang leg.; 4 spec., Tongdao, 20 Aug. 1982, Zhihe Huang leg.; 5 spec., Yizhang, 10 Feb. 1941, Zhelong Pu leg.; 6 spec.; Yizhang, 16 Mar. 1941, Zhelong Pu leg.; 24 spec., Yizhang, 1 Apr. 1942, Zhelong Pu leg.; 34 spec., Nanyue, 4 Apr. 1941, Zhelong Pu leg.; 7 spec., Hengshan, Jun. 1941, Zhelong Pu leg.; 3 spec., Qianyang, An’jiang, 20 Jun. 1965, Zhenyao Chen leg.; 2 spec., Xianghuaihua, Yushuwan, 17 Jun. 1965, Zhenyao Chen leg.; 3 spec., Zhuzhou City, Yanling County, Taoyuandong, Mihua village, 25 May 2014, Renchao Lin, Xiaolin Liu and Chang Pan leg. – Guangxi: 75 spec., Yangshuo, 1985, Shoujian Chen leg.; 37 spec., Hechi, 4 Jun. 1941, Zhelong Pu leg.; 13 spec., Nanning, 19–20 Jun. 1977, Zhihe Huang leg.; 3 spec., Longlin, 22 Mar. 1977, Zhihe Huang leg.; 5 spec., Shangsi County, Hualan village pond, 204 m a.s.l., 6. Jul. 2011, Keqing Song leg.; 1 spec., Jingxi, Bangliang, 6 Aug. 2010, Jianhua Huang leg. – Fujian: 2 ♂♂, 8 spec., Fuzhou, Meifeng, 30 Apr. 1963, Shanxiang Lin leg.; 2 spec., Fuzhou, Meifeng, 9 May 1963, Shanxiang Lin leg.; 9 spec., Fuzhou, Meifeng, 19 May 1963, Shanxiang Lin leg.; 10 spec., Fuzhou, Meifeng, 27 May 1963, Shanxiang Lin leg.; 6 spec., Fuzhou, Meifeng, 17 Jun. 1963, Shanxiang Lin leg.; 4 spec., Fuzhou, Meifeng, 26 Jun. 1963, Shanxiang Lin leg.; 11 spec., Fuzhou, Meifeng, 10 Jun. 1963, Shanxiang Lin leg.; 1 spec., Fuzhou, Meifeng, 31 Jun. 1963, Shanxiang Lin leg.; 3 spec., Fuzhou, Meifeng, 2 Jul. 1963, Shanxiang Lin leg.; 1 spec., Fuzhou, Meifeng, no locality, 8 Jul. 1963, Shanxiang Lin leg.; 9 spec., Fu’an, Apr. 1963, Shanxiang Lin leg.; 2 spec., Fu’an, May 1963, Shanxiang Lin leg.; 7 spec., Fuzhou, West Lake, 15 May 1963, Shanxiang Lin leg.; 1 spec., West lake, 21 May. 1963, Shanxiang Lin leg.; 2 spec., Fujian Agricultural College, 3 Jul. 1964, Yuliang Luo leg.; 2 spec., Wuyi Mount, Xiamei village puddle, 17 Jul. 2010, Fenglong Jia leg.; 2 ♂♂, Nanjing, Hexi town, 13 Jul. 2010, Fenglong Jia leg.; 1♀, Xiamen, Jimei, 19 May 1964, Tongxu Peng leg. – Hainan: 2 ♂♂, 5 ♀♀, 35 spec., Yinggeling, 5 Apr. 2008, light trap, Yuxia Yang leg.; 1 spec., Lingshui, Diaoluoshan, 5 Jan. 1963, Zhenyao Chen leg.; 1 spec., Lingshui, Diaoluoshan, 26 Jul. 1963, Yuzhen Liang leg.; 1 spec., Lingshui, Diaoluoshan, 26 Jul. 1963, Jicai Li leg.; 2 spec., Lingshui, Diaoluoshan, 29 Jul. 1963, Jianqiu Tang leg.; 2 spec., Lingshui, Diaoluoshan, 31 Jul. 1963, Baiming Chen leg.; 2 spec., Lingshui, Diaoluoshan, Xiaomei, 29 Jul. 1963, Baige Chen leg.; 1 ♀, Bawangling, 14 Jun. 1964, Zhenyao Chen leg.; 1 spec., Wanning, Jianling, Houlang, 8–9 Apr. 2013, Weicai Xie leg.; 2 spec., Lingshui, 1 Jan. 1964, Tongxu Peng leg.; 2 spec., Jianfengling, 14 Jul. 1983, Zhihe Huang leg.; 4 spec., Jianfengling, 22 Jun. 1983, Zhihe Huang leg.; 1 spec., Jianfengling, 24 Jun. 1964, Zhenyao Chen leg.; 2 ♀♀, Xinglong, 24 Jul. 1957, Cuiying Li leg.; 1 ♂, Xinglong, 3 Jan. 1964, Tongxu Peng leg.; 1 spec., Sanya, 24 Jul. 1957, Zhelong Pu leg.; 1 spec., Wanning, 17 Jul. 1957, Cuiying Li leg.; 1 ♀, Tongshi, 27 Jul. 1963, Tongxu Peng leg.; 1 spec., Haikou, 15 Jul. 1957, Zhelong Pu leg. – Jiangxi: 3 ♂♂, 2 ♀♀, 50 spec., Jing’an county, Zaodu town, Nanshan village, 29.01° N, 115.16° E, 315 m a.s.l., 19 Jul. 2014, light trap, Renchao Lin leg.; 4 spec., Jing’an County, Guanyinyan, 29.03° N, 115.25° E, 195 m a.s.l., 20 Jul. 2014, light trap, Renchao Lin leg.; 3 spec., Jing’an County, Daqishan Forestry Centre, 28.67° N, 115.07° E, 350 m a.s.l., 16 Jul. 2014, light trap, Renchao Lin leg.; 102 spec., Jing’an County, Zaodu town, Nanshan village, 29°01′ N, 115°16′ E, 315 m a.s.l., 2 Jul. 2015, light trap, Renchao Lin and Yudan Tang leg.; 10 spec., Jiulianshan, Daqiutian, 30 Aug. 2007, light trap, Hong Pang leg.; 9 spec., Jiulianshan, Daqiutian, 31 Aug. 2007, light trap, Hong Pang leg.; 12 spec., Suichuan County, Nanfengmian Nature Reserve, 26°17′04″ N, 114°03′53″ E, 816 m a.s.l., 18 Jul. 2015, Renchao Lin and Yudan Tang leg. (English labels); 9 spec., Jinggangshan, Jingzhushan, 26°31.01′ N, 114°05.9′ E, 640 m a.s.l., 4 May 2010, Fenglong Jia leg.; 2 spec., Lushan, Poyanghu, 10 Aug. 1963, Zhelong Pu leg.; 2 spec., Jiujiang, 24 Aug. 1963, Zhelong Pu leg.; 1 ♀, Nanchang; 1 ♀, Jinggangshan, Luofu, 25 Apr. 2011, Weicai Xie, Zhenyu Jin and Yun Li leg. – Shaanxi: 1 Ƌ, 1 ♀, 19 spec., Chang’an, Xingguoshi, 19 Aug. 1984, Zhihe Huang leg.; 2 spec., Chang’an, Quwei, 21 Jul. 1984, Zhihe Huang leg.; 2 spec., Xi’an, Chanbahe, 11 May 2011, Fenglong Jia leg.; 1 spec., Chang’an, 19 Aug. 1984, Geqiu Liang leg. – Guizhou: 39 spec., Liupanshui, Panxian, 2 May. 1940; 41 spec., Dushan, 10 May 1940; 2 spec., Guiyang, 6 May 1939, Zhelong Pu leg.; 5 spec., Pingba, Maba, 13 Aug. 1982, Zhihe Huang leg.; 1 spec., Anshun, 4 May 1940, Zhelong Pu leg.; 9 spec., Weng’ang town, Maolan Nature Reserve, 25°15′08″ N, 107°53′56″ E, 814 m a.s.l., 24 Jul. 2015, Renchao Lin and YudanTang leg. – Xizang: 2 spec., Xiachayu, no other data. – Macau: 1 ♂, 2 ♀♀, Ludang City, Ecological Reserve, section one, 4–5 Apr. 2013, light trap, Fenglong Jia & Weicai Xie leg.; 6 spec., Ludang City, Ecological Reserve, section one, 9 May 2013, light trap, Weicai Xie leg.; 8 spec., Ludang City, Ecological Reserve, section one, 9 May 2013, light trap, Jinwei Li leg.; 8 spec., Ludang City, Ecological Reserve, section one, 9 May 2013, light trap, Fenglong Jia leg.; 2 spec., Ludang City, Ecological Reserve, section one, 8 Apr. 2014, light trap, Weicai Xie leg.; 1 spec., Ludang City, Ecological Reserve, section one, 28 Apr. 2014, light trap, Fenglong Jia leg.; 1 ♀, no locality, Apr. 2012, Zhiqiang Li leg. – Hong Kong: 3 ♂♂, 2 ♀♀, 75 spec., Fengkeng, 22°31.695′ N, 114°13.450′ E, 13 m a.s.l., 9 Apr. 2014, light trap, Fenglong Jia, Weicai Xie and Jiahuang Chen leg.; 10 spec., Rongshuao, 22°32.646′ N, 114°14.926′ E, 10 m a.s.l., 11 Apr. 2014, Fenglong Jia, Weicai Xie and Jiahuang Chen leg.; 2 spec., Rongshuao, 11 Jun. 2014, Weicai Xie leg.; 2 spec., Wujiaoteng, 9 Jun. 2014, Weicai Xie leg.

Redescription

FORM AND COLOUR. Body length 2.8–3.4 mm, width 1.4–1.7 mm, oblong, moderately convex. Head yellowish to blackish brown, usually frons dark and clypeus yellowish brown ( Fig. 35 ), labrum blackish brown. Pronotum yellowish to reddish brown ( Figs 32, 35–36 ). Elytra same colour but with pronotum sometimes with some black spots. Maxillary palps uniformly yellowish brown. Antennae yellowish brown with club somewhat dark. Labial palps reddish to yellowish brown. Ventral side yellowish brown or dark brown ( Fig. 33 ), legs with apices of femora, tibiae and tarsomeres yellowish brown.

HEAD. Labrum with fine punctures, systematic punctures detectable. Clypeus broad, anterior margin broadly emarginate, slightly expanded in front of eyes, not impressed in front of eyes ( Fig. 35 ), with fine and sparse punctures, systematic punctures slightly coarser than ground punctures. Eyes moderate in size, somewhat emarginate anteriorly, systematic punctures present; interval between eyes ca 4× as wide as one eye. Ground punctures on frons similar to those on clypeus, systematic punctures conspicuous in front of eyes. Maxillary palps long and slender, ca 1.2× as long as width of head, 1 st and 2 nd palpomeres curved inwards, apical palpomere a little shorter than penultimate, slightly bending inwards. Antennae with 9 antennomeres, scape ca 1.5× as long as pedicel, pedicel slightly shorter than antennomeres 3–6 combined, club loosely segmented, with dense pubescence. Mentum ca 1.2× as wide as long, subquadrate, lightly impressed anteromedially, with coarse punctures, never with wrinkles ( Fig. 37 ). Submentum with coarse punctures ( Fig. 37 ).

THORAX. Pronotum ca 2 × as wide as long, widest basally; posterior margin slightly bisinuate with median portion widely curved; ground punctures on pronotum similar to those on head, systematic punctures arranged in two transverse rows ( Figs 35–36 ). Prosternum slightly bulging in middle, not carinate ( Fig. 38 ), pubescent, with transverse groove, protruding anteriorly. Mesoventrite only simply convex posteromedially, without a low transverse ridge ( Fig. 39 ). Metaventrite pubescent, with somewhat convex middle portion, without glabrous area. Metepisterna ca 3.5× as long as wide, subparallel. Scutellum triangular, with similar punctures as on elytra. Ground punctures on elytra similar to those on pronotum, with three conspicuous rows of systematic punctures, dorsal surface without striae but 8–9 striae on underside of elytra usually visible from dorsal side ( Figs 41–42 ) (continuous dark lines with black spots on ventral surface of the elytra, not corresponding with real punctures on dorsal elytral surface, and sometimes not clear in old specimens). Epipleura very wide anteriorly, gradually narrowed, reaching level of first visible abdominal sternite. Femora densely pubescent with apical eighth glabrous ( Figs 33, 40 ). Metatarsomeres with dense white hairs ventrally and some long swimming hairs dorsally. Claws of moderate size, rather strongly curved.

ABDOMEN. All visible abdominal ventrites with dense pubescence; first ventrite not carinate ( Fig. 40 ).

AEDEAGUS. Apex of parameres not dilated inwards, somewhat narrowly rounded near apex. Membranous inner sac with several small dentiform bulges on each side. Median lobe with sharp apex, apex spineformed ( Fig. 52 ).

Differential diagnosis

This species may be closest to H. obscurus ( Müller, 1776) based on form and colour. It can be distinguished from H. obscurus by its smaller size, dorsum with fine punctures, striae on the underside of the elytra usually visible in dorsal view, mesoventrite only simply convex posteromedially, without a transverse ridge or process pointed posteriorly, apex of parameres not dilated inwards and median lobe with a spine-formed apex.

Habitat

Wingspread and occupying typical aquatic habitats such as ponds with rotting leaves, margins of puddles and edges of rivers. It usually flies when it is collected from water and its body surface becomes drier during the daytime. Adults have strong photokinesis and sometimes hundreds of individuals appear at light.

Distribution

China (Chongqing, Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hubei, Hunan, Jiangxi, Macau, Shaanxi, Sichuan, Yunnan, Xizang). Afrotropical: Benin, Botswana, Chad, Congo, Ethiopia, Ghana, Guinea, Kenya, Madagascar, Namibia, Rwanda, South Africa, Sudan, Tanzania, Zambia (Balfour- Browne 1951, 1952, 1957; Hebauer 1996). Palearctic: China, Egypt, Israel, Japan, Lebanon, Saudi Arabia (north), Turkey, Yemen. Oriental: Bangladesh, Burma, China, India, Indonesia (Java, Sumatra, Sunda), Malaysia (peninsula), Nepal, Philippines, Sri Lanka, Thailand ( Fikáček et al. 2015; Hansen 1999; Jäch et al. 2012). New record for Chongqing and Macau.

Figures

Figs 32–40. Helochares pallens (MacLeay, 1825). 32–34. Habitus. 32. Dorsal. 33. Ventral. 34. Lateral. 35. Head and pronotum. 36. Pronotum, dorsolateral. 37. Head, ventral. 38. Prosternum. 39. Mesoventrite with legs. 40. Abdomen.

Figs 41–46. – 41–42. Helochares pallens (MacLeay, 1825). Elytra. 41. Dorsal. 42. Ventral. 43, 45. Paratype of H. vitalisi d’Orchymont, 1919. 43. Data of labels. 45. Habitus, dorsal. 44, 46. Paratype of H. fuliginosus d’Orchymont, 1932. 44. Data of labels. 46. Habitus, dorsal.

Figs 47–55. Aedeagi in species of Helochares Mulsant, 1844. 47. H. fuliginosus d’Orchymont, 1932. 48–49. H. songi sp. nov. 50–51. H. atropiceus Régimbart, 1903. 50. From Guangxi. 51. From Hong Kong. 52. H. pallens (MacLeay, 1825). 53–55. H. obscurus (Müller, 1776). 53. From Xinjiang. 54–55. After Hansen (1987).