CHINA: Yunnan: male, Nabanhe N. R., Mandian, 12.I.2004, Li Li-Zhen & Tang Liang leg. (SHNU); male and female, Nabanhe N. R., Nabancun, N22°10.032, E100°39.359, alt. 720m, 6.V.2009, Hu Jia-Yao & Yin Zi-Wei leg. (SHNU); Hunan: male, Wufeng Town, Houhe N. R., 20. IX.2003, Ohbayashi Nobuo leg. (SHNU)

China (Yunnan, Hunan), Vietnam, Thailand, Borneo, Indonesia.

Holotype. China: Hainan: male, glued on a card with labels as follows: “China: Hainan Prov., Ledong County, Jianfengling N. R., alt. 900m, 16.IV.2010, Feng & Yuan leg.” “Holotype / Dianous fengtingae / Tang & Li” [red handwritten label] (SHNU). Paratypes. male and 4 females, same data as for the holotype. (SHNU); female, Changjiang County, Bawangling, alt. 1000m, 14.XI.2006, Li Li-Zhen leg. (SHNU); 4 females, Changjiang County, Bawangling, alt. 450–650m, 13.IV.2010, Zhu Jian-Qing leg. (female in cPut, female in cRou, rest in SHNU).

Body entirely black, head, pronotum, elytra and basal abdominal tergites with a blue metallic lustre. Antennae blackish brown, with club segments lighter. First two segments of maxillary palpi brownish yellow, last segment brown. Legs blackish with tibiae and tarsi slightly lighter, femora yellowish in basal third.

BL: 4.5–4.9mm; FL: 2.5–2.6 mm.

Proportions of holotype: HW: 63.5, PW: 47, PL: 53, EW: 61, EL: 67.

Head 1.04 times as wide as elytra; interocular area gently inclined inward forming a shallow and broad concavity; punctures round, distinctly delimited, slightly larger on median area than near dorsal margins of eyes, diameter of large punctures about as wide as widest cross section of 2nd antennal segment, interstices smooth, mostly smaller than half diameter of punctures. Antennae when reflexed exceeding posterior margin of pronotum; length of segments from base to apex: 10.0: 7.0: 17.5: 11.0: 9.0: 8.0: 8.0: 7.0: 7.0: 8.0: 10.0.

Pronotum 1.28 times as long as wide, widest slightly before middle and constricted at base; punctures round, partially slightly confluent, distinctly larger than those on frons, interstices smooth, mostly smaller than half diameter of punctures.

Elytra nearly rectangular; punctation on average slightly coarser than that of pronotum, punctures on humeral area mostly distinctly delimited, and those on inner 2/3 portion of elytra (especially those on posterior half) obliquely confluent, interstices similar to those on pronotum.

Length of metatarsi from base to apex: 11.5: 8.5: 5.5: 3.5: 10.5.

Abdomen subcylindrical; 3rd to 6th segments with broad and densely punctate paratergites, paratergites of tergite 4 narrower than greatest width of hind tibia; 7th tergite with an apical membranous fringe; punctures on 3rd tergite as large as one eye facet, interstices smooth.

Male. Seventh sternite (Fig. 29) with a distinct posteriomedian emargination, 8th sternite (Fig. 30) with a broad triangular emargination posteromedially; 9th sternite (Fig. 31) with the apicolateral portion serrate, posterior margin slightly emarginate; 10th tergite (Fig. 32) with the posterior margin broadly rounded. Median lobe of aedeagus (Fig. 18) with an acutely pointed and setose apex (Fig. 19), parameres extending far beyond the apex of median lobe.

Female. Sternite 8 (Fig. 33) pointed posteromedially; valvifer (Fig. 34) with the posterior margin serrate; 10th tergite (Fig. 35) with the posterior margin truncate.

China (Hainan).

The new species is similar to Dianous tonkinensis (Puthz, 1968) from South Asia and Dianous lividus (L. Benick, 1929) from Philippines and Indonesia. It may be distinguished from both by the coarser and less confluent punctation on pronotum and especially on elytra.

CHINA: Yunnan: male, Nabanhe N. R., Bengganglahu, 15.I.2004, Li Li-Zhen & Tang Liang leg. (SHNU); female, Nabanhe N. R., Nabancun, N22°09.305, E100°41.291, alt. 620m, 18.XI.2008, Tang Liang leg. (SHNU)

China (Yunnan), Myanmar, Thailand.

Holotype. China: Jiangxi: male, glued on a card with labels as follows:“China: Jiangxi Prov., Yushan County, Mt. Sanqingshan, alt. 1000–1200m, 16.X.2010, Peng, Zhai & Zhu leg.” “Holotype / Dianous zhujianqingi / Tang & Li” [red handwritten label] (SHNU). Paratypes. 14 males and 19 females, same data as for the holotype (1 pair in cPut, 1 pair in cRou, rest in SHNU); male and female, Sanqingshan, alt. 700–1000m, 4.V.2005, Hu Jia-Yao & Tang Liang leg. (SHNU); Guizhou: male and 2 females, Mt. Fanjing, 23.VII.2003, Li Li-Zhen, Hu Jia-Yao & Tang Liang leg. (SHNU)

Body entirely black with a faint plumbeous lustre, elytra sometimes with brassy reflection. Antennae blackish brown. Maxillary palpi with first segment yellowish, second segment light brown and last segment brown. Legs black with a brownish tint, tibiae and tarsi slightly lighter.

BL: 3.7–4.4 mm; FL: 2.1–2.3mm.

Proportions of holotype: HW: 58.0, PW: 44.5, PL: 49.0, EW: 59.0, EL: 63.5.

Head about as wide as elytra; lateral portions of front slightly rising, medial portion concave; punctures round, distinctly delimited, slightly larger on median area than near dorsal margins of eyes, diameter of large punctures about as wide as apical cross section of 3rd antennal segment, interstices smooth, smaller than or as broad as half diameter of punctures. Antennae when reflexed extending to the posterior margin of pronotum; Length of segments from base to apex: 9.0: 6.5: 9.0: 8.0: 8.0: 5.5: 8.0: 6.0: 7.0: 6.5: 9.0.

Pronotum 1.10 times as long as wide, widest slightly before middle and constricted at base; punctures partially confluent, diameter of large punctures about as wide as apical cross section of 2nd antennal segment, interstices smooth, mostly smaller than or about as broad as half diameter of punctures.

Elytra nearly rectangular; punctation similar to that of the pronotum, punctures on humeral area mostly distinctly delimited, those on medial two thirds obliquely confluent, interstices similar to those on pronotum.

Length of metatarsi from base to apex as 18.5: 8.0: 5.5: 4.0: 11.5.

Abdomen subcylindrical; 3rd to 6th segments with broad and densely punctate paratergites, paratergites of 4th tergite as broad as greatest width of hind tibia; 7th tergite with an apical membranous fringe; punctures on 3rd tergite slightly smaller than one eye facet, interstices with very indistinct microsculpture.

Male. Seventh sternite (Fig. 47) with a very shallow emargination posteromedially, 8th sternite (Fig. 48) with a triangular emargination posteromedially; 9th sternite (Fig. 49) with distinct apicolateral projections, posterior margin slightly serrate and almost straight; 10th tergite (Fig. 50) with posterior margin broadly round. Median lobe of aedeagus (Fig. 45) with a triangularly pointed and setose apex (Fig. 46), a pair of distinct expulsion hooks, parameres extending far beyond the apex of median lobe.

Female. Eighth sternite (Fig. 51) pointed posteromedially; valvifer (Fig. 52) with posterior margin finely serrate; 10th tergite (Fig. 53) with the posterior margin broadly pointed.

China (Jiangxi, Guizhou)

In a few specimens the punctation of pronotum and elytra is strongly confluent as in Fig. 9. Two specimens show more a distinct brassy reflection on elytra and blue metallic reflection on basal tergites (Fig. 10).

The new species slightly resembles Dianous cyaneovirens (Cameron, 1930) from India, Nepal, Bhutan and Dianous bracteatus (Champion, 1920) from India, and Nepal. From both it may be easily distinguished by the faint metallic coloration (Dianous cyaneovirens and Dianous bracteatus: strongly metallic green), and from Dianous bracteatus also by darker legs.

Holotype. China: Yunnan: male, glued on a card with labels as follows:“Zhonghutiao, Hutiaoxia Coun., Yunnan Prov., 24.IV.2005, Huang Hao leg.” “Holotype / Dianous Huanghaoi / Tang & Li” [red handwritten label] (SHNU). Paratypes. 2 males and 5 females, same data as for the holotype. (1 pair in cPut; rest in SHNU); 2 females, Yushuizhai, Lijiang, alt. 2600m, 14.IV.2003, stream moss, G. de Rougemont leg. (cRou)

Body entirely black with a faint plumbeous lustre. Antennae blackish brown, antennal club slightly lighter than preceding segments. Maxillary palpi brownish. Legs black with a brownish tint, tibiae and tarsi slightly lighter.

BL: 4.6–5.0mm; FL: 2.6–2.7mm.

Proportions of holotype: HW: 59.5, PW: 44.0, PL: 50.5, EW: 66.0, EL: 69.5.

Head 0.9 times as wide as elytra; lateral portions of frons slightly raised, median portion concave; punctures round to elliptic, distinctly delimited, slightly larger on median area than near dorsal margins of eyes, diameter of largest punctures about as wide as basal cross section of 2nd antennal segment, interstices smooth, smaller than or as broad as half diameter of punctures. Antennae when reflexed extending to the posterior margin of pronotum; Length of segments from base to apex as 9.5: 6.5: 14.5: 8.5: 7.5: 6.5: 7.0: 5.5: 6.0: 5.5: 8.0.

Pronotum 1.15 times as long as wide, widest slightly before middle and constricted at base; punctures partially confluent, similar in size to those on head, interstices similar to those on frons.

Elytra nearly rectangular; punctation similar to that of the pronotum, punctures on humeral area mostly distinctly delimited, those on posterior half of elytra strongly confluent, forming a narrowly vorticose sculpture.

Relative length of segments of hind legs from base to apex as 15.0: 8.5: 5.5: 3.5: 14.5.

Abdomen subcylindrical; 3rd to 6th segments with broad and densely punctate paratergites, paratergites on 4th segment as broad as largest width of hind tibia; 7th tergite with an apical membranous fringe; punctures on 3rd tergite distinctly smaller than eye facet, interstices smooth.

Male. Seventh sternite (Fig. 56) with a very shallow emargination posteromedially, 8th sternite (Fig. 57) with a broad emargination posteromedially; 9th sternite (Fig. 58) with distinct apicolateral projections, posterior margin finely serrate and almost straight; 10th tergite (Fig. 59) with a shallow emargination at middle of posterior margin. Median lobe of aedeagus (Fig. 54) with a triangularly pointed and setose apex (Fig. 55), parameres extending far beyond the apex of median lobe.

Female. Eighth sternite (Fig. 60) with posterior margin hardly pointed at middle; valvifer (Fig. 61) with posterior margin serrate; 10th tergite (Fig. 62) with the posterior margin rounded.

China (Yunnan).

The new species is similar to Dianous carinipennis (Bernhauer, 1914) and Dianous nilgiriensis Puthz, 1995, both from India. It can be distinguished from the latter two species by the less confluent punctation on pronotum and with vorticose sculpture on posterior half of elytra.

CHINA: Xizang: 2 females, Nielamu County, Zhangmu Town, Lixin village, 27–28.VII.2010, alt. 2400–2600m, Zhu Jian-Qing leg.

China (Xizang), Nepal.

The species was originally described from Nepal and not unsurprisingly was found in China near the border.

China (Guizhou), Myanmar, Thailand.

No Chinese material was examined by us; a photograph of a paratype (cPut) from Myanmar is provided here.

Holotype: CHINA: Yunnan: female, Baoshan Xian, Gongshan Mts., Lujiaba, 2400m, 10.X.1996, K. Ishii et al. leg.

China (Yunnan).

This species was only known from the female holotype, which is actually deposited in “the collection of the Laboratory of Entomology, Tokyo University of Agriculture”, not in “Shanghai Institute of Entomology, Academia Sinica” (Present name: Shanghai Entomology Museum, the Chinese Academy of Science) as original published paper described.

China (Xizang), India, Nepal, Bhutan.

No Chinese material was examined by us, and a photograph of specimen (cPut) from Nepal is provided here.