Rugitermes ursulaesp. nov. is described from a sample collected inside a dead branch in a tropical dry forest of Colombia’s Caribbean coast using molecular information and external morphological characters of the imago and soldier castes. Rugitermes ursulaesp. nov. soldiers and imagoes are the smallest among all described Rugitermes species. The imago’s head capsule coloration is dark castaneous, while the pronotum is contrastingly pale yellow. Our description includes soldier characters, such as subflangular elevation and shape of the antennal sockets, that can help in identification of samples lacking imagoes.