ELECTROPHORETIC COMPARISON OF RUGOPHARYNX LONGIBURSARIS KUNG AND R-OMEGA BEVERIDGE (NEMATODA, STRONGYLOIDEA), WITH THE DESCRIPTION OF R-SIGMA N-SP FROM PADEMELONS, THYLOGALE SPP (MARSUPIALIA, MACROPODIDAE)

An electrophoretic comparison of the nematodes Rugopharynx longibursaris and R. omega, both from Macropus rufogriseus in south-eastern Australia, revealed fixed genetic differences at 4.5% of the 23 enzyme loci examined. The electrophoretic data do not therefore reject the null hypothesis that the two taxa are conspecific. R. longibursaris was found in Tasmania and in the western mainland population of M. rufogriseus, while R. omega occurred only in the eastern mainland population. Implications for the taxonomic status of the western host population are considered. Specimens formerly assigned to R. omega, from Thylogale stigmatica from Queensland, were found to differ at 45.0% of enzyme loci from specimens from M. rufogriseus. Morphological examination revealed differences in the shape of the buccal capsule, the position of the deirid, the morphology of the spicule tip and the presence of a gubernaculum. A new species, R. sigma, is erected for specimens from T. stigmatica, T. thetis and T. calabyi.