A new Syphacia species (Nematoda: Oxyuridae) collected from Bunomys spp. (Rodentia: Muridae) in central Sulawesi, Indonesia.

Syphacia (Syphacia) rifaii sp. n. (Nematoda: Oxyuridae) is described from endemic Bunomys chrysocomus and Bunomys prolatus (Rodentia: Muridae) on Sulawesi Island, Indonesia. The new species is closest morphologically to Syphacia (Syphacia) sulawesiensis , parasitic in Rattus xanthurus from Sulawesi Island, by having large vesicular lateral alae in males, but is readily distinguished by having a smaller body, a round cephalic plate in both sexes, the absence of lateral alae in females, a longer relative distance between excretory pore and vulva, and smaller eggs. Syphacia (S.) rifaii is surmised to be a specific parasite of Bunomys spp. and has evolved from a common ancestor with S. (S.) sulawesiensis on Sulawesi Island.