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.

A total of 333 vials of nematodes collected from three species of Isoodon (representing three individuals of I. auratus, 63 of I. fusciventer and 92 of I. obesulus) held in the Australian Helminthological Collection of the South Australian Museum were examined. Nematodes were identified and the nematode assemblages of the three hosts were compared with each other and with the assemblage of Isoodon macrourus. Two fully identified species were recovered from I. auratus, eight from I. fusciventer and 14 from I. obesulus. None of the species occurred in all three hosts; Labiobulura inglisi (Subuluridae), Peramelistrongylus skedastos (Dromaeostrongylidae) and Asymmetracantha tasmaniensis (Mackerrastrongylidae) all occurred in I. fusciventer and I. obesulus. Only Pe. skedastos was also found in I. macrourus. Sorensen's index of similarity, 27.2 %, showed that I. fusciventer and I. obesulus did not have similar nematode communities and neither were their communities similar to that of I. macrourus, 17.1 % and 39.0 % respectively. Labiobulura inglisi and Linstowinema inglisi were the dominant nematodes in the assemblage of I. fusciventer and La. inglisi was dominant in I. obesulus. The two hosts had nematode assemblages with unique species profiles; one species of Linstowinema in I. fusciventer, three in I. obesulus; a species of Physaloptera in I. obesulus, none in I. fusciventer; four species of strongylid; Asymmetracantha tasmaniensis the most prevalent in I. fusciventer, Peramelistrongylus skedastos the most prevalent in I.obesulus. The size of the geographic range is a probable determinant of the species richness of the nematode assemblages.

A review of the nematode assemblage of the Australian bandicoot, Isoodon macrourus (Peramelidae), from material held in the South Australian Museum with the description of Sprattellus cassonei n. sp. (Mackerrastrongylidae).

A total of 235 vials of nematodes held in the Australian Helminthological Collection of the South Australian Museum from 125 individuals of Isoodon macrourus were examined. The nematode assemblage of I. macrourus, comprising 12 families, including 16 genera and 23 identified species, was compared with the sympatric bandicoot species Perameles nasuta, 20 identified species (Sorensen's index of similarity 0.56) and P. pallescens, 12 identified species (Sorensen's index 0.51). Sprattellus cassonei n. sp. is distinguished from its congeners by having a synlophe with 7-8 ridges with the anterior ventral ridges interrupted, the morphology of the dorsal ray and the branching of the spicule tips. A single male specimen identified as Linstowinema sp. 1. is characterised by seven circles of body hooks, the oesophagus terminating at the level of the seventh circle and robust scale-like spines on the posterior ventral body. A complete description of the species will require additional material, including females. Difficulties in identifying individuals of the genus Mackerrastrongylus to species level are discussed. Overall similarities in the nematode assemblages of the three bandicoot hosts are likely due to shared relationships and similar behaviours.