Characidium chancoense, a new species of South American darter from the Río Cauca drainage, Colombia (Characiformes: Crenuchidae).

Characidium chancoense new species, is described from the transandean upper Río Cauca drainage in Colombia. It can be distinguished from all congeners by its pigmentation pattern that consists of 7-12 vertical bars, most of which are cuneate-shaped with the vertex ending on or just below the lateral-line scale series, except for the last 1-4, which are dorsoventrally elongate rectangular bars that extend well below the lateral line. Characidium chancoense is sympatric with C. caucanum Eigenmann, C. phoxocephalum Eigenmann, C. cf. zebra Eigenmann and C. cf. boavistae Steindachner. Unlike C. caucanum and C. cf. boavistae, C. chancoense does not appear to be sexually dimorphic.