I describe a new species of Riama from the Pacific versant of the Andes in extreme southwestern Colombia. Among the species of Riama, the new species most resembles R. vieta, with which it shares rugose dorsal and ventral scales. Unlike R. vieta, the new species has three postoculars and males lack heavy black spots dorsally and black bands ventrally. Males of the new species have seven to eight femoral pores per leg (total number 14–15) and two scales between the femoral pores (anterior cloacal plate scales paired).