Sinotrisus nomurai Yin, Li, and Zhao, 2010 (Fig. 1B)

Sinotrisus nomurai Yin, Li, and Zhao 2010b: 251; Yin et al. 2012: 49 (redescription).

Type Locality. Tianmushan Mountain, Lin’ an City, Zhejiang Province, China; elevation 1,400 m.

Additional Material Examined. Two ƋƋ: China, Sichuan, Luzhou City, Gulin County (古蔺县), Honglong Lake (红龙湖森林公园), 28°07 ′ 17″N, 105°46 ′ 53″E, 1,620 m, 30.iv.2017, ant nest in rotten wood, Lu QIU leg. (Five ants of the genus Tetramorium Mayr are pinned under the specimens); 1 Ƌ: China: Zhejiang Prov., Linan County, West Tianmushan (西天目山), 12.v.2012, 1,450 m, Wen-Xuan Bi leg. (Five Lasius ants are pinned under the specimen).

Comments. Sinotrisus nomurai was originally described based on two male adults captured in a colony of Lasius ants from the West Tianmu Mountain in Zhejiang, eastern China. The specimen collected in 2012 at West Tianmushan confirms this beetle-ant association. This species is recorded from the eastern part of Sichuan, roughly 1,350 km west of the type locality, and within a nest of Tetramorium ants. Adults were collected during April and May. The population from Sichuan can be readily determined as conspecific with that from the type locality by the unique male sexual characters of this species (Fig. 1B), i. e., enlarged antennomere VI distinctly broader than antennomeres V and VII, deep transverse impression on the vertex and connecting foveae, mesotibiae with an acute apical spur, and large, elongate, and apically bent projection on the ventral margin of the metatrochanter.

Distribution. China: Zhejiang, Sichuan (new provincial record).