Isoodon obesulus

Smales, L. R., Wood, J. A. L. & Chisholm, L. A., 2024, A review and comparison of the nematode assemblages of the Australian golden bandicoot, Isoodon auratus, the quenda, I. fusciventer and southern brown bandicoot, I. obesulus (Peramelidae), from material held in the south Australian museum, International Journal for Parasitology: Parasites and Wildlife 24, pp. 100938-100938 : 100938-

4.4. Isoodon obesulus

Isoodon obesulus , although having a highly fragmented distribution ( Baker and Gynther, 2023, Fig. 1 ), had the most speciose nematode community comprising 14 identified species contained within 12 genera, compared with eight identified species within 10 genera for I. fusciventer . Moreover, the Sorensen’ s index between the two communities was only 27 % similarity. In contrast to I. fusciventer , whose community had high prevalences of both the Seuratidae and the Subuluridae ( Li. inglisi 100 % and La. inglisi 84.1 % prevalence respectively), only the Subuluridae ( La. inglisi 66.3 % prevalence had a similarly high prevalence in the community of I. obesulus . The seuratid Linstowinema cinctum and the dromeostrongylid Peramelistrongylus skedastos had the next highest prevalences at 28.2 % and 18.5 % respectively. The differences in the helminth communities of the two host species are highlighted by the strongylid component. Asymmetracantha tasmaniensis had a prevalence of 25.4 % in I. fusciventer and only 6.5 % in I. obesulus . Mackerrastrongylus mawsonae , prevalence 15.9 % in I. fusciventer , was not found in I. obesulus . Beveridgiella iota , prevalence 9.7 % in I. obesulus was missing from the I. fusciventer nematode community.

Also unique to I. obesulus were the seuratid Li. tasmaniensis and the strongyloidid Parastrongyloides australis . Of the enoplids, Eucoleus longiductus , E. parvulus and E. pseudoplumosus were found in I. obesulus ( Table 5) and only E. longiductus in I. fusciventer ( Table 4). Spratt and Beveridge (2016) reported all three species, E. longiductus , E. parvulus and E. pseudoplumosus from I. obesulus . The collection data from Spratt (2006), however, show that all three species of Eucoleus were described from I. obesulus from New South Wales and Tasmania and E. longiductus was also recorded from Western Australia. This latter record is now known to be from I. fusciventer . The difficulties in identifying capillariids to species are such that the material identified as Eucoleus spp. from both host species could be either one of the listed species or one or more undescribed species. The pneumospirurid, Metathelazia naghiensis Spratt, 1980 , a lung inhabiting species, was not found in this study, and was reported only from histological sections of lungs by Spratt (2002). The onchocercid, Cercopithifilaria johnstoni ( Table 5), a tissue inhabiting species has been recorded previously from I. obesulus (see Spratt and Haycock 1988). The dromeostrongylid, Mackerrastrongylus isoodon , recovered from a Victorian location, is the first recording of the genus in the southern brown bandicoot. There is no simple explanation for this record. Isoodon macrourus , the usual host of M. isoodon , is not found in the collection locality, Anglesea, on the southern Victorian coast. Neither has M. isoodon been reported from Perameles gunnii (Gray) or P. nasuta Geoffroy , long nosed bandicoots, which are sympatric with I. obesulus along parts of Coastal Victoria ( Smales et al., 2023b).

Figures

Fig. 1. Map of Australia showing the distributions of Isoodon auratus (green), Isoodon fusciventer (yellow) and Isoodon obesulus (blue). Abbreviations: NT Northern Territory; NSW New South Wales; Qld Queensland; SA South Australia; Tas Tasmania; Vic Victoria; WA Western Australia. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)