Body moderately large to large (6–12 mm), mostly dark brown; ventral surface reddish brown; dorsal surface dull and glabrous.

Labroclypeus subtrapezoidal, wider than long, widest at base, lateral margins moderately convex and convergent to strongly rounded anterior angles, anterior margin weakly sinuate medially, margins moderately reflexed; surface weakly convex, moderately shiny, finely and densely punctate; frontoclypeal suture indistinctly incised, flat and weakly curved medially; ocular canthus short and triangular, impunctate, with a single terminal seta. Frons dull, with sparse, fine punctures, with single erect setae beside each eye. Antenna yellowish, with 10 antennomeres; club composed of 4 antennomeres in male, straight, rarely longer than 1.5 times as the remaining antennomeres combined; club in female composed of 3 antennomeres, as long as the remaining antennomeres combined. Mentum elevated and slightly flattened anteriorly.

Pronotum moderately wide and strongly convex, lateral margins evenly convex, more strongly narrowed anteriorly towards sharp and slightly produced anterior angles. Anterior margin of pronotum slightly convex, with fine complete marginal line. Posterior angles blunt or strongly rounded. Surface finely and densely punctate, except minute setae glabrous, lateral and lateral anterior margins sparsely setose. Hypomeron not carinate. Scutellum triangular, finely and densely punctate.

Elytra oblong, widest just behind middle, striae distinctly impressed, finely and moderately densely punctate, intervals distinctly convex, with coarse and dense punctures concentrated along striae, with very minute setae in punctures; epipleural edge robust, ending at weakly curved and slightly blunt external apical angle of elytra, epipleura densely setose, apical border with a broad fringe of microtrichomes (100×).

Ventral surface weakly shiny, finely and densely punctate, metasternum sparsely covered with fine, short, or very minute setae, metacoxa glabrous, with a few single setae laterally; abdominal sternites finely and densely punctuate, with a transverse row of coarse punctures, each bearing a robust seta. Mesosternum between mesocoxae as wide as mesofemur. Pygidium weakly convex and dull, densely punctate, without smooth midline, almost glabrous, but with a few longer setae along apical margin; pygidium without strong sexual dimorphism.

Legs moderately wide; femora finely and sparsely punctate; metafemur wide and moderately shiny or dull, anterior margin acute, posterior margin smooth ventrally and only weakly widened in apical half, posterior margin smooth dorsally, with a few short setae basally. Metatibia moderately wide to wide and moderately long, widest at half of metatibial length, dorsal margin sharply carinate, with two groups of spines; lateral face finely and sparsely punctate; ventral edge finely serrated, with four robust equidistant setae, medial face smooth, apex interiorly near tarsal articulation with a shallow sinuation. Tarsomeres with fine, very dense setae ventrally on distal half, neither laterally nor dorsally carinate, dorsally smooth; metatarsomeres with a strongly serrated ridge ventrally and glabrous; first metatarsomere slightly shorter than two following tarsomeres combined, one third of its length longer than dorsal tibial spine. Protibia short, bidentate; anterior claws symmetrical, basal tooth of both claws bluntly truncate at apex.

Aedoeagus. Phallobasis with a more or less long median ventral extension.

So far seven species from Himalaya and the type species from Myanmar have been formally assigned to Tetraserica (Ahrens 2004; Ahrens and Fabrizi 2009). Most other oriental species (so far grouped with ‘Neoserica’) await taxonomic revision. Tetraserica differs from closely related genera Microserica Brenske, 1894, and Trioserica Moser, 1922, by the lacking ventral carina of hypomeron. From Microserica it also differs by the lacking sexual dimorphism of the pygidium, from Trioserica by the bidentate protibia. In contrast to the Microserica, species of Tetraserica are active at night and are attracted by light.

The genus is distributed almost in the entire Oriental region; we know described species so far assigned to “Neoserica” from Philippines, Indochina, Sumatra, and Borneo (Ahrens 2004). Except in Meghalaya and Himalaya, the genus does not occur on Indian subcontinent south of the Ganges.

Holotype: ♂ [China] “Mt. Daqingshan, Longzhou, Guangxi, 24.IV.1963, 600–700m, leg. Shi Yongshan” (IZAS). Paratype: 1 ♂ [China] “Mt. Daqingshan, Longzhou, Guangxi, 13.IV.1963, 360m, leg. Wang Shuyong” (ZFMK).

Body length: 9.2 mm, length of elytra: 7 mm, width: 5.5 mm.

Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Antennal club 1.1 times as long as remaining antennomeres combined. Eyes small; ratio of diameter/interocular width: 0.53. Ratio of length of metepisternum/metacoxa: 1/1.63. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin with a blunt tooth. Metatibia short and wide, ratio width/length: 1/3.1; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 1A–C. Habitus: Fig. 1D.

Figure 1. 

A–D Tetraserica daqingshanica sp. n. (holotype) E–H T. sculptilis Ahrens sp. n. (holotype) I–L T. wangtongensis sp. n. (holotype). A, E, I aedeagus, left side lateral view C, G, K aedeagus, right side lateral view B, F, J parameres, dorsal view D, H, L habitus (not to scale). Scale: 0.5 mm.

Female unknown.

Body length: 9.2 mm, length of elytra: 7.0–7.3 mm, width: 5.5–5.9 mm.

The new species differs from all other so far known Tetraserica species by the blunt tooth at the posterior margin of the metafemur.

The new species is named after the type locality, Mt. Daqingshan.

Holotype: ♂ “China: Hubei; Dahongshan 1700m, Shuizhou VI-2003 leg. Ying et al.” (ZFMK). Paratypes. 1 ♂ [China] “Hekou, Southeast of Yunnan, 9.VI.1956, 1200m, leg. Panfilov” (IZAS), 1 ♂ [China] “Luxi, Yunnan, 22.V.1980, leg. Li Hongxing” (IZAS).

Body length: 9.1 mm, length of elytra: 7.3 mm, width: 5.4 mm.

Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.6. Antennal club 1.2 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.7. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin with a blunt tooth. Metatibia short and wide, ratio width/length: 1/3.2; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 1E–G. Habitus: Fig. 1H.

Female unknown.

Body length: 9.1–9.8 mm, length of elytra: 7.3–7.4 mm, width: 5.4–6.0 mm.

Tetraserica sculptilis sp. n. is in the external shape and morphology of the male genitalia very similar to T. daqingshanica. It differs only in the shape of the parameres: the left paramere is more narrow in T. sculptilis sp. n., its dorsal margin weakly and evenly curved (Fig. 1E).

From the Latin word sculptilis – modelled, sculptured, with reference to the shape of the aedeagus.

Holotype: ♂ [China] “Wang Tong, to light, 29/4/07” (ZFMK). Paratypes: 1 ♂ [China] “Huangniushi, Mt. Jiulianshan, Jiangxi, 16.VI.1975, leg. Zhang Youwei” (IZAS), 1 ♂ [China] “Luoyang, Lianxian County, Guangdong, 22.VI.1965, leg. Zhang Youwei” (IZAS).

Body length: 9.1 mm, length of elytra: 6.9 mm, width: 5.8 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.6. Antennal club 1.3 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.7. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight, without blunt tooth. Metatibia short and wide, ratio width/length: 1/3.2; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 1I–K. Habitus: Fig. 1L.

Female unknown.

Body length: 8.2–9.1 mm, length of elytra: 6.5–6.9 mm, width: 5.5–5.8 mm.

Tetraserica wangtongensis sp. n. is in the external shape and morphology of the male genitalia similar to T. daqingshanica and T. sculptilis. It differs by the lacking tooth at the posterior margin of metafemur and in the shape of the parameres: the right paramere is straight (in dorsal view) and not curved as in T. daqingshanica and T. sculptilis (Fig. 1J).

Tetraserica wangtongensis sp. n. is named after its type locality, Wang Tong.

Holotype: ♂ “Guangxi, Maoershan, 2011-VI-4/ LW-1066” (ZFMK).

Body length: 8.3 mm, length of elytra: 6.8 mm, width: 3.1 mm.

Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.61. Antennal club 1.2 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.5.

Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin with a blunt tooth. Metatibia short and wide, ratio width/length: 1/2.84; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 2A–C. Habitus: Fig. 2D.

Figure 2. 

A–D Tetraserica maoershanensis sp. n. (holotype) E–J T. fikaceki sp. n. (holotype) K–N T. changjiangensis sp. n. (holotype). A, E, K aedeagus, left side lateral view C, I, M aedeagus, right side lateral view B, H, L parameres, dorsal view F parameres, distal view G parameres, ventral view D, J, N habitus (not to scale). Scale: 0.5 mm.

Female unknown.

Tetraserica maoershanensis sp. n. is in the external shape and morphology of the male genitalia similar to T. daqingshanica and T. sculptilis. It differs by the shape of the parameres: the dorsal lobe of the right paramere is short and does not exceed the length of the ventral lobe (Fig. 2C).

The new species is named after its type locality, Maoershan.

Holotype: ♂ “China, Hainan Isl., 4-6.v.2011 Limushan Mts. Frst administr. Centre (at light) 19°10'30"N, 109°44'33"E, 630m, M. Fikáček, V. Kubeček & L. Li leg.” (NMPC). Paratypes: 2 ♂♂, 1 ♀ [China] “Nankai Mingya, Baisha, Hainan, 25–26.V.2008, 450m, leg. Ba Yibin, Lang Juntong” (HBUM, ZFMK), 1 ♂ [China] “East of Mts. Bawangling, Changjiang, Hainan, 5-7.VI.2008, 750m, leg. Ba Yibin, Lang Juntong” (HBUM).

Body length: 9.7 mm, length of elytra: 7 mm, width: 6 mm.

Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.6. Antennal club 1.2 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.8. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight, without blunt tooth. Metatibia short and wide, ratio width/length: 1/2.7; basal group of dorsal spines of metatibia at first third of metatibial length. Aedeagus. Fig. 2E–I. Habitus: Fig. 2J.

Tetraserica fikaceki sp. n. is in the external shape and morphology of the male genitalia similar to T. wangtongensis. It differs by the shape of the parameres: the dorsal lobe of the right paramere (in lateral view) is curved ventrally (while being straight in T. wangtongensis) (Fig. 2I), the left paramere is reduced in size (Fig. 2E).

Body length: 8.0–9.7 mm, length of elytra: 6.0–7.0 mm, width: 4.8–6 mm. Head of the female paratype is missing.

The new species is named after one of the collectors of the type series, Martin Fikáček (Prague).

Holotype: ♂ “Bawangzhen, Changjiang, Hainan, 5–7.VI.2008, leg. Ba Yibin, Lang Juntong” (HBUM). Paratype: 1 ♂ “Mt. Jianfengling, Hainan, 10.VI.1965” (IZAS).

Body length: 8.4 mm, length of elytra: 6.5 mm, width: 5.4 mm.

Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.63. Antennal club 1.2 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.67.

Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight, without blunt tooth. Metatibia short and wide, ratio width/length: 1/2.74; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 2K–M. Habitus: Fig. 2N.

Female unknown.

Body length: 7.7–8.4 mm, length of elytra: 6.1–6.5 mm, width: 5.0–5.4 mm.

Tetraserica changjiangensis sp. n. differs from the similar T. fikaceki sp. n. by the shape of the parameres: the dorsal lobe of the right paramere (in lateral view) is extremely short (Fig. 2M), the left paramere is distinctly longer and curved externally at the apex (Fig. 2K, L).

The new species is named after its type locality, Changjiang.

Holotype: ♂ “China: Sichuan; Wolong Reserve, Sigulian Shan, 31°09'N, 103°06'E v.2006, 1500–1800m leg. V. Siniaev” (ZFMK). Paratypes: 1 ♂ “Suifu (nr) Sz. China/ DC Graham coll. Aug 25-7, ‘29” (USNM), 1 ♂ “Szechuen China DC Graham/ bet Yachow and Mupin Jun.23-6 ‘29 2000-3000ft.” (USNM), 3 ♂♂ “Minzhuzhen, Lan'gao County, Shaanxi, 4.VII.2003, leg. Yuan Caixia, Liu Yushuang” (HBUM), 1 ♂ “Longju, Wanxian County, Sichuan, 18.VI.1995, 2500m, leg. Wang Shuyong” (IZAS), 1 ♂ “Foping, Shaanxi, 26.VI.1999, 890m, leg. Zhang Youwei” (IZAS), 1 ♂ “Chongqing, Jinfoshan, 2010-VI-13, 713m” (IZAS), 1 ♂ “Xiuqizhen, Chengkou, Chongqing, 13.VII.2003, leg. Yuan Caixia, Liu Yushuang” (HBUM), 1 ♂ “Ningshan, Shaanxi, VIII.1982, light trap” (NUYS), 1 ♂ “Zhongmiao, Bikou, Wenxian County, Gansu, 24.VI.1998, 700m, leg. Yuan Decheng” (IZAS), 1 ♂ “China, Sichuan 12.-14.VII.1995 Baoxing env., cca 50km NNW of Yaan 30°22'N, 102°50'E M. Trýzna et O. Šafranek lgt.” (CPPB).

Body length: 7.6 mm, length of elytra: 5.9 mm, width: 4.8 mm.

Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.6. Antennal club 1.2 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.4.

Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight, without blunt tooth. Metatibia short and wide, ratio width/length: 1/3; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 3A–C. Habitus: Fig. 3D.

Figure 3. 

A–D Tetraserica sigulianshanica sp. n. (holotype) E–H T. damaidiensis sp. n. (holotype) I–L T. shunbiensis sp. n. (holotype). A, E, I aedeagus, left side lateral view C, G, K aedeagus, right side lateral view B, F, J parameres, dorsal view D, H, L habitus (not to scale). Scale: 0.5 mm.

Female unknown.

Body length: 6.6–7.6 mm, length of elytra: 5.1–5.9 mm, width: 3.9–4.8 mm.

Tetraserica sigulianshanica sp. n. differs from the similar T. fikaceki sp. n. by the shape of parameres: the dorsal (= basal) lobe of the right paramere (in lateral view) is long, filiform, and strongly curved (Fig. 3A), the left paramere is much longer than that of T. fikaceki sp. n. (Fig. 2K, L).

The new species is named after its type locality, Sigulian Shan.

Holotype: ♂ “China: E-Yunnan; Damaidi 2500m, Guangnan near Vietnam VII-2003 leg. Li et al.” (ZFMK). Paratypes: China. 1 ♂ “China: E-Yunnan; Damaidi 2500m, Guangnan near Vietnam VII-2003 leg. Li et al.” (ZFMK), 1 ♂ “Jiangfu Famuchang, Jiangle, Fujian, 22.VI.1991, 470m, leg. Yang Longlong” (IZAS), 1 ♂ “Mt. Dawuling, Xinyi, 24.V.2002, leg. Jia Fenglong, No. En-048009” (SYUG), 2 ♂♂ “Luoxiang, Jinxiu, Guangxi, 15.V.1999, 400m, leg. Xiao Hui” (IZAS), 1 ♂ “Mt. Daweishan, Pingbian, Yunnan, 18.VI.1956, 1500m, light trap, leg. Huang Keren etc.” (IZAS), 1 ♂ “Mt. Yaoshan, 6.V.1938”(IZAS), 1 ♀ “Beidou, Napo, Guangxi, 9, 11–13.IV.1998, 550m, leg. Wu Min, Qiao Geixa” (IZAS), 1 ♂ “Nongxin, Napo, Guangxi, 12.IV.1998, 440m, leg. Qiao Gexia” (IZAS), 1 ♂ “Beidou, Napo, Guangxi, 9.IV.1998, 550m, leg. Qiao Gexia” (IZAS). Vietnam. 1 ♂ “N Vietnam (Tonkin) Ha Noi (city) 4.-5.V.1990 Vit. Kubáň leg. (ZFMK), 4 ♂♂, 10 ♀♀ “N-Vietnam Sa Pa env., Lao Cai Prov. 22°19'52"N, 103°50'35"E 1630–1680m 23.–27.V.1999 leg. Fabrizi, Jäger, Ahrens” (ZFMK), 1 ♂, 1 ♀ “N-Vietnam Bac Ha env., Lao Cai Prov. 22°32'05"N, 104°32'32"E 980–1000m 28.–30.V.1999 leg. Fabrizi, Jäger, Ahrens” (ZFMK), 2 ♀♀ “N.-Vietnam Fan Si Pan near Sapa, 1500–1950m 17.–30.VI.1999 A. Kallies leg.” (ZFMK), 1 ♂ “Vietnam N (Sa Pa) Lao Cai Prov., 250km from Hanoi bearing 31°, Sa Pa vill. env. Hoang Lien Son Nat. Res. 21.–23.6.1998 1250m leg. A. Napolov” (CNAR), 8 ♂♂ “Vietnam N (Sa Pa) Lao Cai Prov., 250km from Hanoi bearing 31°, Sa Pa vill. env. Hoang Lien Son Nat. Res. 27.V.–15.VI.1995 1250m leg. A. Napolov” (CNAR), 11 ♂♂ “Vietnam N (Sa Pa) Lao Cai Prov., 250km from Hanoi bearing 31°, Sa Pa vill. env. Hoang Lien Son Nat. Res. 27.5.–3.6.1998 1250m leg. A. Napolov” (CNAR), 1 ♂ “Vietnam N (Sa Pa) Lao Cai Prov., 250km from Hanoi bearing 31°, Sa Pa vill. env. Hoang Lien Son Nat. Res. 16.–20.VI.1998 1250m leg. A. Napolov” (CNAR).

Body length: 7.6 mm, length of elytra: 5.8 mm, width: 4.6 mm.

Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.67. Antennal club 1.3 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.5. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight, without blunt tooth. Metatibia short and wide, ratio width/length: 1/3.21; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 3E–G. Habitus: Fig. 3H.

Body length: 6.9–7.6 mm, length of elytra: 5.1–5.8 mm, width: 4.0–4.6 mm. Female has the antennal club composed of three lamellae, short, as long as the remaining antennomeres combined; eyes as large as those in male.

The new species differs from the other known Tetraserica species by having both parameres simple, not being divided in two lobes.

The new species is named after its type locality, Damaidi.

Holotype: ♂ “Shunbi, Yangbi, Yunnan, 16.VIII.2009, leg. Shi Fuming” (HBUM).

Body length: 8.9 mm, length of elytra: 6.3 mm, width: 5 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.66. Antenna missing in holotype. Ratio of length of metepisternum/metacoxa: 1/1.5. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight, without blunt tooth. Metatibia short and wide, ratio width/length: 1/3.4; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 3I–K. Habitus: Fig. 3L.

Female unknown.

The new species differs from T. damaidiensis in the shape of the parameres: the left paramere is straight instead of being curved dorsally (Fig. 3I), the right paramere is slender in dorsal view, lacking the basal dorsal tooth (Fig. 3J) which is present in T. damaidiensis.

The new species is named after its type locality, Shunbi.

Holotype: ♂ [China] “Nonggang, Longzhou, Guangxi, 15.VI.2000, 330m, leg. Chen Jun” (IZAS).

Body length: 7.5 mm, length of elytra: 5.5 mm, width: 4.6 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes small; ratio of diameter/interocular width: 0.48. Antennal club 1.1 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.48. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight, without blunt tooth. Metatibia short and wide, ratio width/length: 1/3.3; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 4A–C. Habitus: Fig. 4D.

Figure 4. 

A–D Tetraserica longzhouensis sp. n. (holotype) E–H T. yaoquensis sp. n. (holotype) I–L T. longipenis sp. n. (holotype). A, E, I aedeagus, left side lateral view C, G, K aedeagus, right side lateral view B, F, J parameres, dorsal view D, H, L habitus (not to scale). Scale: 0.5 mm.

Female unknown.

Tetraserica longzhouensis sp. n. differs from all other species with straight or slightly convex posterior margin of metafemur by the small eyes, short ventral process of phallobasis being at maximum subequeal to half of the length of the phallobasis, strongly asymmetric phallobasis (dorsal view), right paramere being simple, and left paramere having the ventral lobe shorter than the dorsal one.

The new species is named after its type locality, Longzhou.

Holotype: ♂ [China] “Yao District, Mengla, Yunnan, 11.V.1991, leg. Liu Guangchun, Cai Wanzhi” (NUYS).

Body length: 8.3 mm, length of elytra: 6.5 mm, width: 5.1 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.62. Antennal club 1.6 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.5. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight, without blunt tooth. Metatibia short and wide, ratio width/length: 1/3.2; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 4E–G. Habitus: Fig. 4H.

Female unknown.

Tetraserica yaoquensis sp. n. differs from all other species with straight posterior margin of metafemur by the short ventral process of the phallobasis being subequal to half of the length of phallobasis, right paramere being simple and basiventrally strongly widened towards apex, and left paramere having two lobes.

The new species is named after its type locality, Yaoqu.

Holotype: ♂ “China: E-Yunnan; Damaidi 2500m, Guangnan near Vietnam VII-2003 leg. Li et al.” (ZFMK). Paratypes: 1 ♂ “China, SE-Yunnan Xichou-E env. 1400–1700m, 13.–18.5.95/ 23°11–16'/ 104°41–49' L.+R. Businský lgt.” (CPPB), 1 ♂ [China] “Yunnan 2000–2500m 25.42N 100.08E Cangshan mts. E slope 21.VI.92 David Král leg.” (NMPC), 1 ♂ [China] “Mts. Laoshan, Weihuo, Tianlin, Guangxi, 4.VI.2002, 1400m, leg. Jiang Guofang” (IZAS), 1 ♂ [China] “Luodian, Guizhou, 29.V.1981, 500m, leg. Li Fasheng” (CAU), 2 ♂♂ [China] “Xinyicun, Xichang, Sichuan, 18.V.1974, leg. Han Yinheng” (IZAS), 3 ♂♂ [China] “Meng'e, Xishuangbanna, Yunnan, 19.V.1958, leg. Hong Chunpei” (IZAS, ZFMK).

Body length: 7 mm, length of elytra: 5.3 mm, width: 4.6 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.7. Antennal club 1.2 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.4. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight, without blunt tooth. Metatibia short and wide, ratio width/length: 1/3.3; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 4E–G. Habitus: Fig. 4H.

Female unknown.

Body length: 7.0–7.8 mm, length of elytra: 5.3–5.6 mm, width: 4.4–4.6 mm.

Tetraserica longipenis sp. n. differs from T. yaoquensis by the smaller body, shorter antennal club, and the right paramere being simple, long and narrow.

The species name is derived from the combined Latin words, longus – long and penis – male copulation organ, with reference to the long parameres of the species.

Holotype: ♂ “China, S-Yunnan Prov. Xishuangbanna 23km NW Jinghong Na Ban village 680m 22°10.04'N, 100°39.52'E, 20.V.2008, leg. A. Weigel, LF” (NME). Paratypes. 1 ♂ [China] “Xiaomengyang, Yunnan, 7.V.1957, 850m, leg. Pu Fuji” (IZAS), 1 ♂ [China] “Yunnan, Nabanhe Nature Reserve, Guomenshan, 2009-VI-16/ LW-1230” (ZFMK).

Body length: 7.6 mm, length of elytra: 5.8 mm, width: 5 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.63. Antenna missing in holotype. Ratio of length of metepisternum/metacoxa: 1/1.69. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight, without blunt tooth. Metatibia short and wide, ratio width/length: 1/3.36; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 5A–C. Habitus: Fig. 5D.

Figure 5. 

A–D Tetraserica jinghongensis sp. n. (holotype) E–H T. menglongensis sp. n. (holotype) I–L T. tianchiensis sp. n. (holotype). A, E, I aedeagus, left side lateral view C, G, K aedeagus, right side lateral view B, F, J parameres, dorsal view D, H, L habitus (not to scale). Scale: 0.5 mm.

Female unknown.

Body length: 6.8–7.6 mm, length of elytra: 5.2–5.8 mm, width: 4.1–5.0 mm.

Tetraserica jinghongensis sp. n. differs from all other species with long ventral phallobasal process by the simple left paramere being not separated into lobes, right paramere having no brush of spines and being composed of two lobes: its dorsal lobe is narrow, evenly curved and sharply pointed.

The species name is named after its type locality, Jinghong Na Ban village.

Holotype: ♂ [China] “Menglong, Yunnan, 22.IV.1982, light trap, leg. Jiang Shengqiao” (IZAS).

Body length: 7.6 mm, length of elytra: 5.8 mm, width: 4.3 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.59. Antennal club 1.2 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.64. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight, without blunt tooth. Metatibia short and wide, ratio width/length: 1/3.23; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 5E–G. Habitus: Fig. 5H.

Female unknown.

Tetraserica menglongensis sp. n. differs from T. jinghongensis by the slightly lighter colour, bilobate left paramere, as well as the right paramere having the dorsal lobe shorter than the ventral one (Fig. 5E).

The new species is named after its type locality, Menglong.

Holotype: ♂ “Tianchi, Jianfeng, Hainan, 13.IV.1980, 900m, leg. Wang Shuyong” (IZAS). Paratype: 1 ♂ “Tianchi, Jianfeng, Hainan, 18.IV.1980, 750m, leg. Wang Shuyong” (ZFMK).

Body length: 9.1 mm, length of elytra: 6.9 mm, width: 5.7 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.63. Antennal club 1.3 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.56. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight, without blunt tooth. Metatibia short and wide, ratio width/length: 1/3.24; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 5I–K. Habitus: Fig. 5L.

Female unknown.

Body length: 9.1–10.5 mm, length of elytra: 6.9–8.4 mm, width: 5.7–6.1 mm.

Tetraserica tianchiensis sp. n. differs from T. jinghongensis by dorsal lobe of the right paramere being wide, with a sickle-shaped, large apical hook (Fig. 5J).

The new species is named after its type locality, Tianchi.

Holotype: ♂ [China] “Yunnan, Lianghe, 2011-V-4, N: 24.789, E: 98.264, 1130m/ LW-1316” (ZFMK).

Body length: 9.7 mm, length of elytra: 7.3 mm, width: 5.5 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.59. Antennal club 1.1 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.56. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin with a large sharp hook. Metatibia short and wide, ratio width/length: 1/3.1; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 6A–C. Habitus: Fig. 6D.

Figure 6. 

A–D Tetraserica liangheensis sp. n. (holotype) E–H T. graciliforceps sp. n. (holotype) I–L T. pingjiangensis sp. n. (holotype). A, E, I aedeagus, left side lateral view C, G, K aedeagus, right side lateral view B, F, J parameres, dorsal view D, H, L habitus (not to scale). Scale: 0.5 mm.

Female unknown.

Tetraserica liangheensis sp. n. differs from all other known Tetraserica species by the large and sharp hook at the posterior margin of metafemur.

The new species is named after its type locality, Lianghe.

Holotype: ♂ “China, W Yunnan prov., mts. 60km E Tengchong, 2200m, 19.–22.v.2006, S. Murzin & I. Shokhin” (CPPB). Paratype: 1 ♂ “Yunnan 2200-2500m 24.57N 98.45E 8-16/5. Gaoligong mts. Vit Kubáň leg. 1995” (ZFMK).

Body length: 8.9 mm, length of elytra: 7.2 mm, width: 5.7 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes small; ratio of diameter/interocular width: 0.5. Antennal club 1.2 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.6. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin with a large sharp hook. Metatibia short and wide, ratio width/length: 1/3.2; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 6E–G. Habitus: Fig. 6H.

Female unknown.

Body length: 8.9–9.8 mm, length of elytra: 7.1–7.2 mm, width: 5.5–5.7 mm.

Tetraserica graciliforceps sp. n. differs from T. longzhouensis by the following features: phallobasis in dorsal view is only slightly asymmetric; left and right parameres are simple, without two lobes; posterior angles of the pronotum are strongly rounded.

The species name is derived from the combined Latin words, gracilis – fine, and forceps – forceps, with reference to the fine and simple parameres of the species.

Holotype: ♂ “China: Hunan; Mupu Mt. 1600m, Pingjiang VIII-2003, leg. Li et al.” (ZFMK). Paratypes: China. 1 ♀ “China: Hunan; Mupu Mt. 1600m, Pingjiang VIII-2003, leg. Li et al.” (ZFMK), 2 ♂♂, 1 ♀ “China: Hubei; Dahongshan 1700m Shuizhou VI-2003 leg. Ying et al.” (ZFMK), 1 ♂ “China: S-Yunnan Prov. Xishuangbanna 20km NW Jinghong Man Dian (NNNR) 720m 22°07.80'N, 100°40.05'E, 26.v.2008, light trap, leg. A. Weigel” (NME), 1 ♂ “Jingdong, Yunnan, 30.V.1956, 1170m, leg. Krischanovskna” (IZAS), 2 ♂♂ [China] “Jingdong, Yunnan, 22.V, 1.VI.1956, 1170m, leg. Zagulaev, Polov” (IZAS), 2 ♂♂ [China] “Mt. Junzishan, Shizong, Yunnan, 14,16.VII.2006, leg. Mao Benyong etc.” (HBUM), 1 ♂ “Jingdong, Yunnan, 29.IV.1957, 1200m, leg. Zagulaev” (IZAS), 1 ♂ [China] “Yunnan, Honghe, Hekou, Binlangzhai Shuiku, 2011-V-14/ LW-1076” (IZAS), 4 ♂♂ [China] “Jingdong, Yunnan, 26,30.V.1956, 1170m, leg. Krischanovskna, light trap” (IZAS), 3 ♂♂ [China] “Jingdong, Yunnan, 1,3.VII.1956, 1170m, leg. Krischanovskna, light trap” (IZAS), 8 ♂♂ [China] “Jingdong, Yunnan, 2,5,8,12,20,21,28.VI.1956, 1170m, leg. Krischanovskna, light trap” (IZAS), 1 ♂ [China] “Jingdong, Yunnan, 17.V.1957, 1200m, leg. Montschadskij” (IZAS), 1 ♂ [China] “Jingdong, Yunnan, 8.IV.1957, 1200m, leg. Montschadskij” (IZAS), 7 ♂♂, 1 ♀ [China] “Jingdong, Yunnan, 10.V.1957, 1200m, leg. Montschadskij” (IZAS), 1 ♂ [China] “22 km Northeast of Jingdong, 12.V.1957,leg. Montschadskij” (IZAS), 4 ♂♂ [China] “Jingdong, Yunnan, 23,31.V.1956, 1170–1300m, leg. Ivanov, light trap” (IZAS), 2 ♂♂ [China] “Jingdong, Yunnan, 3.VI.1956, 1170m, leg. Zagulaev” (IZAS), 4 ♂♂ [China] “Jingdong, Yunnan, 30.VI.1956, 1170m, leg. Zagulaev” (IZAS), 1 ♂ [China] “Dongjiafen, Jingdong, Yunnan, 27.VI.1956, 1250m, leg. A. Shnitnikov” (IZAS), 1 ♂ [China] “Fulong, Fangcheng, Guangxi, 23.V.1999, 200m, leg. Ke Xin” (IZAS), 1♂ [China] “Fulong, Fangcheng, Guangxi, 25.V.1999, 200m, leg. Zhang Xuezhong” (IZAS), 1 ♂ [China] “Hongqi Forestry Farm, Shangsi, Guangxi, 28.V.1999, 300m, leg. Zhang Xuezhong” (IZAS), 3 ♂♂ [China] “Banbaxiang, Fangcheng, Guangxi, 16.V.2000, 550m, leg. Li Wenzhu” (IZAS), 2 ♂♂ [China] “Huanian (Eshan, Yunnan), 15.VI.(19)83, No.312,319” (IZAS), 3 ♂♂ [China] “Mengla, Jinping, Yunnan, 17,20.IV.1956, 370m, leg. Huang Keren et.al.” (IZAS), 2 ♂♂ [China] “Menglun, Yunnan, 22.IV.1982, leg. Jiang, light trap” (IZAS), 1 ♂ [China] “Menglun, Yiwubanna, 8.VII.1964, 650m, leg. Zhang Baolin” (IZAS). Myanmar. 1 ♂ “Burma (Myanmar) E Shan state Kengtung (Kyaingtong) J. Rejsek 14.–15.6.1997” (ZFMK). Vietnam. 1 ♂ “N Vietnam (Tonkin) Ha Noi (city) 4.–5.V.1990 Vit. Kubáň leg. (ZFMK), 1 ♂ “Vietnam, Cuc Phong, 100km SE of Hanoi; V-1993; leg. Michio Hori” (ZFMK), 1 ♂ “Vietnam N. Tonkin Cuc-Phong Nat. Park 2.–12.V.1991 E. Jendek leg.” (ZFMK), 45 ♂♂, 44 ♀♀ “N-Vietnam Bac Ha env., Lao Cai Prov., 22°32‘05‘'N, 104°17‘32‘‘E 980-1000m 28.–30.V.1999 leg. Fabrizi, Jager, Ahrens” (ZFMK), 1 ♂ “N. Vietnam: Sontay, 400m, 20.V.1963 leg. Le Van Dyk” (Coll. Kabakov), 1 ♂ “N. Vietnam: Sonla Songma, 500m, 3.V.1990 leg. Schorkov” (Coll. Kabakov), 1 ♂ “N. Vietnam: 40km NE Thainguyen, 300m, 8.V.1963, leg. O. Kabakov” (Coll. Kabakov), 1 ♂ “S. Vietnam (Cat Tien) 120 km NNE Ho Chi Minh, Cat Tien Nat. Park 30.5.–15.6.1995 leg. A. Napolov” (CNAR), 17 ♂♂ “Vietnam N (Sa Pa) Lao Cai Prov., 250km from Hanoi bearing 31°, Sa Pa vill. env. Hoang Lien Son Nat. Res. 27.5.–3.6.1998 1250m leg. A. Napolov” (CNAR, ZFMK), 2 ♂♂ “Vietnam N (Sa Pa) Lao Cai Prov., 250km from Hanoi bearing 31°, Sa Pa vill. env. Hoang Lien Son Nat. Res. 27.V.-3.VI.1998 1250m leg. A. Napolov” (CNAR, ZFMK), 1 ♂ “Vietnam N (Sa Pa) Lao Cai Prov., 250km from Hanoi bearing 31°, Sa Pa vill. env. Hoang Lien Son Nat. Res. 16.–20.VI.1998 1250m leg. A. Napolov” (CNAR), 3 ♂♂ “Vietnam N (Sa Pa) Lao Cai Prov., 250km from Hanoi bearing 31°, Sa Pa vill. env. Hoang Lien Son Nat. Res. 25.VI.–5.VII.1998 1250m leg. A. Napolov” (CNAR), 3 ♂♂ “Vietnam N (Sa Pa) Lao Cai Prov., 250km from Hanoi bearing 31°, Sa Pa vill. env. Hoang Lien Son Nat. Res. 21.–23.6.1998 1250m leg. A. Napolov” (CNAR), 3 ♂♂ “Vietnam-N (Na Hang) 160km from Ha Noi, NE env. of Na Hang, 26.5.–6.6.1996 150–200m leg. A. Napolov & I. Roma” (CNAR), 1 ♂ “X-DA3434 - Vietnam, N. Vietnam: Hanoi Prov., Ba Vi National Park (at light) 21–24.vi.2012 L. Bartolozzi, S. Bambi, F. Fabiano, E. Orbach” (MZUF). Thailand. 2 ♂♂, 3 ♀♀ “Thailand, Nam Nao, Phetchabua; 16°5'N,101°40'E; 19.V.1999; leg. K. Masumoto” (ZFMK), 1 ♂, 1 ♀ “Phu Rua NP (900m alt.), Loei P., NE Thai. 26–30.IV.2006 Takakuwa, M. leg.” (ZFMK), 3 ♂♂, 1 ♀ “N. Thailand, Chiang Mai, Erawan Resort; 22.IV.1992; leg. Kazuo Kawano” (ZFMK), 1 ♂, 2 ♀♀ “N. Thailand, Nan, Wiang Sa; 14.V.1993; leg. S. Ohmomo” (ZFMK), 1 ♂ “839493 Tetraserica ThaiSpMU09_1 Thailand S. Murzin 28./31.5.2009 Chiang Dao Hill resort (100km N of Chiang Mai) 600m/ 839493” (ZFMK), 1 ♂, 2 ♀♀ “Thailand bor. Chiang Dao env., 21.5.–4.6.1995 lgt. M. Snizek” (ZFMK), 2 ♂♂ “NW Thailand 24.-27.4.1991 Chom Thong leg. Pacholátko/ TS98” (CPPB), 1 ♂ “Thai 11–15.V.1998 Nan-Pha Khab Pacholátko & Dembický leg.” (CPPB), 1 ♂ “NW Thailand, 1991 Chow Thong, 24.–27.4. 18.26N, 98.41E L. Dembicky leg.” (NHMW), 1 ♂ “Thailand Chiangmai Prov.; Fang (Agr Exp. Station), 600 m 14.VI.1965” (BPBM), 2 ♂♂, 1 ♀ “N. Thailand: Angkhai village, Samoeng Dist. Chiang Mai Prov., 9–11.v.1999 K. Masumoto leg,” (ZFMK), 1 ♂ “N. Thailand: Chiang Mai Pref., Ban Angkhai, Samoeng Dist., 750 m, 15–20.V.1998 K. Matsumoto leg.” (ZFMK). Laos. 1 ♂ “Laos, 21°09'N, 101°19'E Louangnamtha pr. Namtha → Muang Sing, 5-31.v.1997, 900-1200m Vit Kubáň leg./ LS11” (CPPB), 1 ♂ “Laos centr., 27.IV.–1.V.1997, 70km NE Vientiane Ban Phabat env., 150m, N18°16.1', E103°10.9' E. Jendek & Šauša leg.” (CPPB), 1 ♂ “Laos, Bolikhamxai pr. 18°16'N, 103°11'E 70km NEE Vientiane, 27-30.iv.1997, 150m, Vit Kubáň leg.” (CPPB), 2 ♂♂ “N. Laos Louang Namtha 1.5.1996 I. Pjushtch lg” (ZFMK), 35 ♂♂, 19 ♀♀ “Laos P.D.R. Xieng Khowang 14–20. May 1994 K. Miura leg.” (ZFMK), 2 ♂♂ “NE-Laos: Hua Phan prov.; Ban Saleui, Phou Pan (Mt.) 20°12'N, 104°01'E 11.iv.–15.v.2012, 1300–1900 m leg. C. Holzschuh → ZFMK Ankauf 2012/13” (ZFMK), 5 ♂♂ “Laos, La Oudomxay 16.6.2005, ex. coll. Sabatinelli” (ZFMK), 4 ♂♂ “Laos-N, Louang Namtha circ. 04.05.1996, I. Pjushtch lg” (ZFMK).

Body length: 10.0 mm, length of elytra: 7.5 mm, width: 6.0 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.6. Antennal club 1.2 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.6. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin with a blunt tooth. Metatibia short and wide, ratio width/length: 1/2.9; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 6I–K. Habitus: Fig. 6L.

Tetraserica pingjiangensis sp. n. differs from all other Tetraserica species with a blunt tooth at the posterior margin of metafemur by the long and narrow left paramere.

The new species is named after its type locality, Pingjiang.

Body length: 8.8–10.0 mm, length of elytra: 6.9–7.5 mm, width: 5.4–6.0 mm. Female has the antennal club composed of three lamellae, short, as long as remaining antennomeres combined; eyes are as large as those in male.

Holotype: ♂ [China] “Yunnan, Wanding, 2011-IV-29, N: 24.086, E: 98.072, 900m/ LW-1247” (ZFMK). Paratype: 1 ♂ [China] “Yunnan, Wanding, 2011-IV-29, N: 24.086, E: 98.072, 900m/ LW-1247bis” (IZAS).

Body length: 9.3 mm, length of elytra: 6.9 mm, width: 5.4 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes large; ratio of diameter/interocular width: 0.72. Antennal club 1.5 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.56. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin with a large sharp hook. Metatibia short and wide, ratio width/length: 1/3.13; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 7A–C. Habitus: Fig. 7D.

Figure 7. 

A–D Tetraserica wandingensis sp. n. (holotype) E–H T. tonkinensis (Moser) comb. n. (lectotype) I–L T. xichouensis sp. n. (holotype). A, E, I aedeagus, left side lateral view C, G, K aedeagus, right side lateral view; B, F, J parameres, dorsal view D, H, L habitus (not to scale). Scale: 0.5 mm.

Female unknown.

Body length: 8.8–9.3 mm, length of elytra: 6.9–7.1 mm, width: 5.4–5.6 mm.

Tetraserica wandingensis sp. n. differs from T. liangheensis by the larger eyes (ratio diameter/interocular distance: 0.72 vs. 0.59) and dorsal lobe of the right paramere being very small and bent basally.

The new species is named after the type locality, Wanding.

Lectotype (here designated): ♂ [Vietnam] “Tonkin Montes Mauson April, Mai 2-3000' H. Fruhstorfer/ tonkinensis Mos.” (ZMHB). Paralectotypes: 1 ♀ [Vietnam] “Tonkin Montes Mauson April, Mai 2-3000' H. Fruhstorfer/ tonkinensis Mos.” (ZMHB), 5 ♀♀ [Vietnam] “Tonkin Montes Mauson April, Mai 2-3000' H. Fruhstorfer” (ZMHB).

1 ♂ [China] “Luoxiang, Jinxiu, Guangxi, 15.V.1999, 400m, leg. Li Wenzhu” (IZAS).

Body length: 9.0 mm, length of elytra: 7.0 mm, width: 5.9 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes large; ratio of diameter/interocular width: 0.66. Antennal club 1.2 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.45. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin with a large sharp hook. Metatibia short and wide, ratio width/length: 1/3.25; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 7E–G. Habitus: Fig. 7H.

Body length: 8.7–9.0 mm, length of elytra: 6.7–7.0 mm, width: 5.4–5.9 mm. Female has small eyes (ratio of diameter/interocular width: 0.6) and antennal club composed of 3 antennomeres being as long as the remaining antennomeres combined.

The species is recorded for the first time for China.

Holotype: ♂ “China, SE Yunnan, Xichou - E env. 1400–1700m, 13.18.5.95/ 23°22–26'N/ 104°41–49'E L.+R. Businský lgt.” (CPPB).

Body length: 9.0 mm, length of elytra: 6.7 mm, width: 5.8 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes large; ratio of diameter/interocular width: 0.7. Antennal club 1.2 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.6. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin with a large sharp hook. Metatibia short and wide, ratio width/length: 1/3.4; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 7I–K. Habitus: Fig. 7L.

Female unknown.

Tetraserica xichouensis sp. n. differs from the very similar T. tonkinensis by the smaller dorsal lobe of the right paramere.

The new species is named after its type locality, Xichou.

Holotype: ♂ [China] “Meng'e, Xishuangbanna, Yunnan, 19.V.1958, 1050–1080m, leg. Hong Chunpei” (IZAS). Paratypes: 1 ♂ [China] “Menghai, Xishuangbanna, Yunnan, 19.VII.1958, 1200–1600m, leg. Wang Shuyong” (IZAS), 1 ♂ [China] “Menghun, Xishuangbanna, Yunnan, 18.V.1958, 1200–1400m, leg. Zhang Yiran” (IZAS), 1 ♂ [China] “Yunnan, Huanglianshan, 2012-V-9, 1800m/ LW-1277” (IZAS), 1 ♂ [China] “Meng'e, Xishuangbanna, Yunnan, 19.V.1958, 1050–1080m, leg. Hong Chunpei” (ZFMK).

Body length: 7.4 mm, length of elytra: 5.7 mm, width: 4.3 mm. Body reddish brown. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes large; ratio of diameter/interocular width: 0.7. Antennal club 1.2 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.5. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight. Metatibia short and wide, ratio width/length: 1/3.2; basal group of dorsal spines of metatibia at first third of metatibial length. Aedeagus. Fig. 8A–C. Habitus: Fig. 8D.

Figure 8. 

A–D Tetraserica mengeana sp. n. (holotype) E–H T. changshouensis sp. n. (holotype) I–L T. shangsiensis sp. n. (holotype). A, E, I aedeagus, left side lateral view C, G, K aedeagus, right side lateral view B, F, J parameres, dorsal view D, H, L habitus (not to scale). Scale: 0.5 mm.

Female unknown.

Body length: 7.4–8.6 mm, length of elytra: 5.7–7 mm, width: 4.3–5.9 mm.

Tetraserica mengeana sp. n. differs from all other species with a brush of robust trichome-like spines at the base of the right paramere by the left paramere being split into two filiform branches behind the middle.

The new species is named after its type locality, Meng'e.

Holotype: ♂ [China] “Nanmu Garden, Changshou, Sichuan, 9.VI.1994, 450m, leg. Zhang Youwei” (IZAS). Paratype: 1 ♂ [China] “Mt. Xingdoushan, Lichuan, Hubei, 22.VII.1989, light trap, 810m, leg. Wang Shuyong” (ZFMK).

Body length: 8.8 mm, length of elytra: 6.7 mm, width: 5.3 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.65. Antennal club as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.57. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight. Metatibia short and wide, ratio width/length: 1/3.35; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 8E–G. Habitus: Fig. 8H.

Female unknown.

Body length: 8.0–8.8 mm, length of elytra: 6.0–6.7 mm, width: 5.0–5.3 mm.

Tetraserica changshouensis sp. n. differs from all other species with a brush of robust trichome-like spines at the base of the right paramere by the left paramere being composed of two lobes and the ventral lobe of the right paramere being abruptly and strongly widened at apex.

The new species is named after its type locality, Changshou.

Holotype: ♂ [China] “Hongqi Forestry Farm, Shangsi, Guangxi, 29.V.1999, 300m, leg. Ke Xin” (IZAS). Paratypes: 1 ♂ [China] “Nonggang, Longzhou, Guangxi, 21.V.1982, 240m, leg. Li Fasheng” (CAU), 1 ♂ [China] “Fu'ai, Pingxiang, Guangxi, 17.VI.1976, leg. Zhang Baolin” (ZFMK), 2 ♂♂ [China] “Hong Kong: Lantau I: San Shek Wan; v.1988” (BPBM), 1 ♂ [China] “Hongqi Forestry Farm, Shangsi, Guangxi, 29.V.1999, 300m, leg. Ke Xin” (IZAS), 1 ♂ [China] “Taojiang, Leishan, Guizhou, 5.VII.1988, 1000m, leg. Yang Longlong, light trap” (IZAS).

Body length: 8.1 mm, length of elytra: 6.2 mm, width: 4.6 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes large; ratio of diameter/interocular width: 0.76. Antennal club as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.61. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight. Metatibia short and wide, ratio width/length: 1/3.13; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 8I–K. Habitus: Fig. 8L.

Female unknown.

Body length: 7.0–8.1 mm, length of elytra: 5.6–6.7 mm, width: 4.4–4.8 mm.

The new species differs from the similar T. xichouensis sp. n. by the left paramere being evenly curved without being clearly bent, and having a tiny lateral tooth before apex which is absent in T. xichouensis.

The new species is named after its type locality in Shangsi prefecture (Guangxi province).

Holotype: ♂ [China] “Yunnan, Ruili, 2011-IV-27, N: 24.059, E: 97.955, 825m/ LW-1216” (ZFMK).

Body length: 8.1 mm, length of elytra: 5.8 mm, width: 4.8 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.63. Antennal club 1.2 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.74. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight. Metatibia moderately long and wide, ratio width/length: 1/3.54; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 9A–C. Habitus: Fig. 9D.

Figure 9. 

A–D Tetraserica ruiliensis sp. n. (holotype) E–H T. linaoshanica sp. n. (holotype) I–L T. ruiliana sp. n. (holotype). A, E, I aedeagus, left side lateral view C, G, K aedeagus, right side lateral view B, F, J parameres, dorsal view D, H, L habitus (not to scale). Scale: 0.5 mm.

Female unknown.

Tetraserica ruiliensis sp. n. differs from all species with straight posterior margin of metafemur, long ventral phallobasis process, and right paramere without brush of spines by the right paramere being simple, not composed of two lobes.

The new species is named after its type locality, Ruili.

Holotype: ♂ [China] “Mts. Linaoshan, Langping, Tianlin, Guangxi, 28.V.2002, 1400m, leg. Jiang Guofang” (IZAS).

Body length: 8.8 mm, length of elytra: 6.6 mm, width: 5.2 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.63. Antennal club as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.5. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight. Metatibia moderately long and wide, ratio width/length: 1/3.69; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 9E–G. Habitus: Fig. 9H.

Female unknown.

Tetraserica linaoshanica sp. n. differs from all Tetraserica species with a brush of robust trichome-like spines at the base of the right paramere by the left paramere possessing a small lateral basal tooth.

The new species is named after its type locality, Mt. Linaoshan.

Holotype: ♂ [China] “Huyu County, Ruili, Yunnan, 11.VI.1956, 1400m, leg. Zhou Benshou” (IZAS).

Body length: 9 mm, length of elytra: 7 mm, width: 5.3 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large; ratio of diameter/interocular width: 0.63. Antennal club 1.3 times as long as remaining antennomeres combined. Ratio of length of metepisternum/metacoxa: 1/1.55. Metafemur dull, anterior margin acute, without submarginal serrated line; anterior row of setae-bearing punctures absent; posterior margin straight. Metatibia moderately long and wide, ratio width/length: 1/3.47; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus. Fig. 9I–K. Habitus: Fig. 9L.

Female unknown.

Tetraserica ruiliana sp. n. differs from all Tetraserica species with a brush of robust trichome-like spines at the base of the right paramere by the dorsal lobe of the right paramere convexly widened and elongate.

The new species is named after its type locality, Ruili.

Holotype: ♂ [China] “Cangchang, Anhua, Hunan, 15.VII.2004, leg. Wang Jiliang” (HBUM). Paratypes: 2 ♂♂ [China] “Hong Kong: N.T. Taipokau 12.VII.1965 Hand Net/ Lee Kit Ming & Hai Wai Ming Malaise Trap Bishop Museum” (BPBM, ZFMK), 1 ♂ [China] “Hong Kong: N.T. Taipokau 27.VI.1964/ M.J. Voss & Wai Ming Hui Collectors Bishop Museum” (BPBM), 1 ♂ [China] “Hong Kong: N.T. Taipokau 20.VI.1964/ Lee Kit Ming & Hai Wai Ming Light Trap Bishop Museum” (BPBM), 1 ♂, 2 ♀♀ [China] “Shekou, Fu‘an, Fujian, 26.VII.1963, leg. Zhang Youwei” (IZAS), 1 ♀ [China] “Shekou, Fu‘an, Fujian, 27.VII.1963, leg. Zhang Youwei” (IZAS), 2 ♂♂ [China] “Mt. Jiulianshan, Longnan, Jiangxi, 6.VI.1975, leg. Zhang Youwei” (IZAS), 1 ♂ [China] “Sidu, Guidong county, Hunan, 10.VII.2008, 774m, leg. Yang Ganyan” (IZAS), 2 ♂♂, 2 ♀♀ [China] “Qiliqiao, Chong'anxingcun, Fujian, 7,12,13.VII.1963, 840m, leg. Zhang Youwei” (IZAS).

Body length: 7.2 mm, length of elytra: 5.2 mm, width: 4.2 mm.

Labroclypeus surface with a few erect setae. Disc of frons with a few single setae. Smooth area in front of eye approximately 4 times as wide as long. Eyes large; ratio of diameter/interocular width: 0.82. Antennal club 1.4 times as long as remaining antennomeres combined.

Ratio of length of metepisternum/metacoxa: 1/1.5. Metafemur with a serrated continuous line beside anterior margin, with fine sparse punctures behind line each bearing a short seta.

Metatibia moderately long, ratio width/length: 1/3.25; basal group of dorsal spines of metatibia behind middle; beside dorsal margin in basal half with a blunt carina being partly finely serrate.

Aedeagus. Fig. 10A–C. Habitus: Fig. 10D.

Figure 10. 

A–D Tetraserica anhuaensis sp. n. (holotype) E–H T. leishanica sp. n. (holotype) I–L T. yaoanica sp. n. (holotype). A, E, I aedeagus, left side lateral view C, G, K aedeagus, right side lateral view B, F, J parameres, dorsal view D, H, L habitus (not to scale). Scale: 0.5 mm.

Female unknown.

Body length: 6.8–7.2 mm, length of elytra: 5.0–5.2 mm, width: 3.8–4.2 mm.

T. anhuaensis sp. n. differs in a number of characters from all so far known Tetraserica species: metafemur possessing a serrated continuous line beside anterior margin and fine sparse punctures with short setae behind line; the labroclypeus and frons having a few erect setae on disc; basal group of dorsal spines situated behind the middle of metatibia; metatibia beside dorsal margin in basal half with a blunt carina being partly finely serrate.

The new species is named after its type locality, Anhua.

Holotype: ♂ [China] “Leishan, Guizhou, 28.VI.1988, 800m, leg. Yin Huifen” (IZAS). Paratypes: 1 ♂ [China] “Mts. Fanjingshan, Jiangkou, Guizhou, 13.VIII.1988, 550m, leg. Yang Xingke” (ZFMK), 1 ♂ [China] “Mts. Fanjingshan, Jiangkou, Guizhou, 19.VIII.1988, 550m, leg. Yang Xingke” (IZAS), 1 ♂ [China] “Jiuniutang, Mao‘ershan, Guangxi, 13.VII.1985, 1100m, leg. Liao Subai” (IZAS).

Body length: 6.8 mm, length of elytra: 5 mm, width: 4 mm. Body reddish brown. Labroclypeus surface with a few erect setae. Disc of frons with a few single setae. Smooth area in front of eye approximately 4 times as wide as long. Eyes large; ratio of diameter/interocular width: 0.81. Antennal club 1.4 times as long as remaining antennomeres combined.

Ratio of length of metepisternum/metacoxa: 1/1.68. Metafemur with a serrated continuous line beside anterior margin, with fine sparse punctures behind line each bearing a short seta.

Metatibia moderately long, ratio width/length: 1/3.64; basal group of dorsal spines of metatibia behind middle; beside dorsal margin in basal half with a blunt carina being partly finely serrate.

Aedeagus. Fig. 10E–G. Habitus: Fig. 10H.

Female unknown.

Body length: 6.8–7.7 mm, length of elytra: 5.0–5.6 mm, width: 4.0–4.6 mm.

Tetraserica leishanica sp. n. is similar to T. anhuaensis externally and in the shape of male genitalia. T. leishanica differs by the reddish brown body colour, more slender metatibia (ratio length/width: >3.6), longer metacoxa. It also differs by the shape of the parameres: the left paramere is straight behind the base (while it is curved in T. anhuaensis), with a long basal lobe (basal lobe in T. anhuaensis is short); the right paramere is more strongly curved externally at apex than in T. anhuaensis.

The new species is named after its type locality, Leishan.

Holotype: ♂ [China] “Yaoan, Lianxian County, Guangdong, 28.VI.1965, leg. Zhang Youwei” (IZAS). Paratypes: China. 1 ♂ “Qiliqiao, Chong‘anxingcun, Fujian, 12,13.VII.1963, 840m, leg. Zhang Youwei” (ZFMK), 1 ♂ “Mt. Jiulianshan, Longnan, Jiangxi, 8.VI.1975, light trap, leg. Zhang Youwei” (IZAS), 1 ♀ “Daqiu Forestry Farm, Mt. Jiulianshan, Longnan, Jiangxi, 11.VI.1975, light trap, leg. Zhang Youwei” (IZAS), 1 ♂ “Mt. Jiulianshan, Longnan, Jiangxi, 8.VI.1975, light trap, leg. Zhang Youwei” (IZAS), 1♂ “Changguling Forestry Farm, Mts. Jinggangshan, Jiangxi, 4.VII.1975, light trap” (IZAS), 1 ♂ “Xinzuochang, Boluo, Guangdong, 3.VI.1965, leg. Zhang Youwei” (IZAS), 1 ♂ “Dong'an, Hunan, 20.V.(19)54” (IZAS), 1 ♂ “Guangxi, Shangsi Shiwandashan 2011-VII-7, 263m” (IZAS). Vietnam. 3 ♂♂ “Vietnam-N (Na Hang) 160km from Ha Noi, NE env. of Na Hang, 3.–14.6.1996 150-200m leg. A. Napolov & I. Roma” (CNAR, ZFMK), 1 ♂ “S. Vietnam (Cat Tien) 120 km NNE Ho Chi Minh, Cat Tien Nat. Park 30.5.-15.6.1995 leg. A. Napolov” (CNAR).

Body length: 7.2 mm, length of elytra: 5.4 mm, width: 4.3 mm. Body reddish brown. Labroclypeus surface with a few erect setae. Disc of frons with a few single setae. Smooth area in front of eye approximately 4 times as wide as long. Eyes large; ratio of diameter/interocular width: 0.86. Antennal club 1.3 times as long as remaining antennomeres combined.

Ratio of length of metepisternum/metacoxa: 1/1.68. Metafemur with a serrated continuous line beside anterior margin, with fine sparse punctures behind line each bearing a short seta.

Metatibia moderately long, ratio width/length: 1/3.82; basal group of dorsal spines of metatibia behind middle; beside dorsal margin in basal half with a blunt carina being partly finely serrate.

Aedeagus. Fig. 10I–K. Habitus: Fig. 10L.

Female unknown.

Body length: 6.6–7.9 mm, length of elytra: 4.9–6.0 mm, width: 4.1–4.6 mm. Female has small eyes (ratio of diameter/interocular width: 0.51) and the antennal club composed of 3 antennomeres being as long as the remaining antennomeres combined.

Tetraserica yaoanica sp. n. is very similar to T. leishanica external and in the shape of male genitalia. It differs by the shape of parameres only: basal lobe of the left paramere is short (basal lobe in T. leishanica is long); basal lobe of the right paramere is wide and more than half as long as the paramere (short in T. leishanica).

The new species is named after its type locality, Yaoan.

Figure 11. 

Distribution of Tetraserica species: T. jinghongensis sp. n., T. longipenis sp. n., T. mengeana sp. n., T. menglongensis sp. n., T. ruiliana sp. n., T. sculptilis sp. n., T. shangsiensis sp. n., T. shunbiensis sp. n., T. sigulianshanica sp. n., T. tianchiensis sp. n., T. tonkinensis (Moser), T. yaoanica sp. n., and T. yaoquensis sp. n.

Figure 12. 

Distribution of Tetraserica species: T. anhuaensis sp. n., T. changjiangensis sp. n., T. changshouensis sp. n., T. damaidiensis sp. n., T. daqingshanica sp. n., T. fikaceki sp. n., T. graciliforceps sp. n., T. leishanica sp. n., T. liangheensis sp. n., T. linaoshanica sp. n., T. longzhouensis sp. n., T. maoershanensis sp. n., T. pingjiangensis sp. n., T. ruiliensis sp. n., T. wandingensis sp. n., T. wangtongensis sp. n., and T. xichouensis sp. n.