Two New Species of the Genus Heterakis (Heterakidae) from the Genera Echymipera, Isoodon and Perameles (Peramelidae), Bandicoots from Papua New Guinea and Australia.

PURPOSE: To identify and describe any new nematode species of the genus Heterakis Dujardin, 1845 (Heterakidae Railliet & Henry, 1914) found in bandicoots (Peramelidae Gray, 1825) collected from Australia and Papua New Guinea and held in the South Australian Museum, Adelaide.

METHODS: All the relevant specimens registered in the South Australian Museum were examined as temporary wet mounts, after clearing in lactophenol, using an Olympus BH-2 microscope with differential interference optics. Measurements were made with an eyepiece micrometer and figures drawn using a drawing tube.

RESULTS: Heterakis balamukensis n. sp. was described from Echymipera kabulu (Lesson, 1828) collected from Balamuk station, Bensbach River, Papua New Guinea and Heterakis oweni n. sp. was described from Isoodon macrourus (Gould, 1842) collected from Papua New Guinea, and Queensland, Australia. Heterakis sp. females were identified from I. macrourus from the Northern Territory and Perameles pallescens Thomas, 1923 from Queensland, Australia. A key to the valid species of Heterakis from mammals is given.

CONCLUSIONS: The heterakid fauna of mammals now comprises eight species: the cosmopolitan species Heterakis spumosa Schneider, 1886 as well as H. balamukensis n. sp., H. fieldingi Smales, 1996, H. oweni n. sp. and H. sirawii Smales, 2016 from Australasia, H. dahomensis (Gendre, 1911) from Africa, and H. inglisi Gupta & Trevadi, 1982 and H. yamagutii Gupta & Trevadi, 1982 from India. Two species have been declared species inquirenda; H. equispicularis Uphadyyay, 2017 and H. verrucosa Molin, 1860, while H. rattui Ghambir, Gyaneswori, Tarnita, Indrani & Zenith, 2008 falls as a junior synonym of H. spumosa. No infections of the cosmopolitan species infecting rodent hosts, Heterakis spumosa Schneider, 1866, were found in bandicoots.