A NEW THOMASOMYS

Among the material collected near Papallacta is a previously unknown murid rodent belonging to the sigmodontine genus Thomasomys Coues. Formerly construed broadly to include southeastern Brazilian taxa (e.g., by Osgood, 1933; Ellerman, 1940; Cabrera, 1961; Pine, 1980), Thomasomys has subsequently been restricted (Voss, 1993; González, 2000) to a smaller but still speciose group that is endemic to tropical Andean cloud forests from Venezuela to Bolivia. Apparently, the center of diversity for the genus includes eastern Ecuador, where the new species described below may occur sympatrically with at least seven other congeners.