Tetraserica namnaoensis, Fabrizi, Silvia, Dalstein, Vivian & Ahrens, Dirk, 2019

Fabrizi, Silvia, Dalstein, Vivian & Ahrens, Dirk, 2019, A monograph on the genus Tetraserica from the Indochinese region (Coleoptera, Scarabaeidae, Sericini), ZooKeys 837, pp. 1-155 : 41

Tetraserica namnaoensis sp. n. Figures 14, 51

Type material examined.

Holotype: ♂ "Thailand, Nam Nao, Phetchabua; 16°5'N, 101°40'E; 19.V.1999; leg. K. Masumoto" (ZFMK). Paratypes: 1 ♂ "Thailand, Nam Nao, Phetchabua; 16°5'N, 101°40'E; 19.V.1999; leg. K. Masumoto" (ZFMK), 1 ♂ "Laos Bolikhamxai pr., 18°16'N, 103°11'E, 70 km NEE Vientiane, 27-30.iv.1997, 150 m, Vít Kubáň leg./ Coll. P. Pacholátko / LS52/ 190 Sericini Asia spec." (CPPB), 1 ♂ "X-DA4881 labcode VD107 Thailand, Chiang Dao Hill Resort (100 km N of Chiang Mai) 600 m, 28.v- 8.vi.2009, S. Murzin leg, / Tetraserica spTH_63/ sp THV63" (ZFMK), 4 ♂♂, 1 ♀ "Laos P.D.R.: Xieng Khowang 14-20.May. 1994, K. Miura leg./ coll D. Ahrens" (ZFMK), 1 ♂ "Thai 17-24/5.91 Chiang Dao mts. 19.25'N, 98.52E lgt. D. Kral 1000 m" (NMPC), 1 ♂ "Laos. Xieng Khouang 29.IV.1919. R.V. de Salvazza" (NHMUK).

Description.

Length of body: 9.3 mm; length of elytra: 7.3 mm; maximum 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: 0.77. Ratio of length of metepisternum/metacoxa: 1/1.83. Metatibia moderately long and wide, ratio width/length: 1/3.67; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus: Fig. 14 I–K. Habitus: Fig. 14L.

Variation.

Length of body: 9.3-11.0 mm; length of elytra: 7.3-8.2 mm; maximum width: 5.5-6.8 mm. Female: Eyes as large as in male; antennal club composed of three joints, short, as long as remaining antennomeres combined.

Diagnosis.

Tetraserica namnaoensis sp. n. is very similar to T. shangsiensis Liu et al., 2014 and T. smetsi sp. n. in shape of the aedeagus. The new species differs from these two species by the median lamina of its phallobase being distinctly curved and evenly narrowed from the base to apex, rather than being straight and strongly narrowed after the basal third.

Etymology.

The new species is named after the type locality, Nam Nao (adjective in the nominative singular).