Abstract. Ruptitermes arboreus (Emerson) is a litter-feeder soldierless termite that builds arboreal cartonated nests. In this paper, we describe and illustrate arboreal nests of R. arboreus, while also describing a fully clayish nest built upon the trunk of a fallen tree. Additionally, we provided physical and populational parameters for two nests. We also illustrate all castes except alates and record two termitophilous species occurring inside the nests.