Abstract
A new genus and new species of carabid beetle, Yalongaphaenops erwini gen. et sp. nov., is described from mountains SW of Mianning City, Sichuan Province, China. This finding, from one side, extends the known distribution of Chinese hypogean trechines, and from another, it raises the upper limit of their vertical distribution to nearly 4000 m. Photographs of the habitus and major taxonomic characters, including the male genitalia, right mandible, and microsculpture patterns of the integument are supplied. The type locality of the new taxon is mapped. Yalongaphaenops gen. nov. shows some similarities with the genus Shiqianaphaenops Tian, 2016 from eastern Guizhou and the genus Boreaphaenops Uéno, 2002 described from Hubei, China. However, the direct relationships of the new genus remain unclear. Further new discoveries of hypogean trechines in Sichuan are necessary to evaluate possible variation of major characters in allied taxa. Although Y. erwini sp. nov. was collected at an elevation exceeding 3800 m a.s.l., it conforms to the upper limit of the forest zone being approximately on par with the vertical distribution of some high altitude hypogean trechine species in other parts of the globe.