Rhabdias singaporensis n. sp. (Rhabditida: Rhabdiasidae) from the lungs of Calotes versicolor (Squamata: Agamidae) from Singapore is described and illustrated. Rhabdias singaporensis n. sp. represents the 77th species assigned to the genus, the eighth of the Asian region, and the second from Singapore. The distinguishing characteristic of the new species is the location of the excretory pore. In all species of Rhabdias for which excretory pore location data are available, the excretory pore is situated just posterior to the level of the nerve ring; in R. singaporensis, it lies near the esophageointestinal junction.