Weaver, HayleeSmales, L R2015-12-101525-2647http://hdl.handle.net/1885/61109Three new species of Syphacia Seurat 1916 (Oxyurida: Oxyuridae) are described from rodents (Rodentia: Muridae) in Queensland, Australia. Syphacia (Syphacia) helidonensis n. sp. from Pseudomys gracilicaudatus (Gould 1845) can be distinguished from all other species by a suite of characters including an oval-shaped cephalic plate, elongated laterally with dorso-ventral constriction at the level of laterally placed amphids and cephalic papillae, lateral but not cervical alae, and a single pair of postanal papillae. Syphacia (Syphacia) boodjamullaensis n. sp. from Zyzomys argurus (Thomas, 1889) also has an oval-shaped cephalic plate, elongated laterally with dorso-ventral constriction at the level of laterally placed amphids and cephalic papillae, a single pair of postanal papillae, neither cervical nor lateral alae, and spicule 77 m long. Syphacia (Syphacia) carnarvonensis n. sp. from Pseudomys delicatulus (Gould, 1842) with an oval-shaped cephalic plate, elongated laterally with dorso-ventral constriction at level of laterally placed amphids and cephalic papillae and a single pair of postanal papillae, also has both cervical and lateral alae, small body size, males 690-865μm, and eggs 77-86μm long, 24-29μm wide. A key to the species of Syphacia from the Australian Bioregion is given, and the potential for as yet undiscovered species in the region is discussed.Keywords: Muridae; Oxyurida; Oxyuridae; Pseudomys; Pseudomys delicatulus; Pseudomys gracilicaudatus; Rodentia; Syphacia; Zyzomys; Zyzomys argurus Australia; Biogeography; Muridae; Oxyuridae; Pseudomys; Syphacia; Taxonomy; Zyzomys201010.1654/4405.12016-02-24