An Hypothesis on the Evolution of Herpetostrongylinae (Trichostrongyloidea: Nematoda) in Australian Marsupials, and Their Relationships With Viannaidae, Parasites of South American Marsupials.

Abstract

Herpetostrongylinae is redefined. A Woolleya-like parasite in Gondwanaland didelphoids is proposed as the ancestral stock of the Herpetostrongylinae parasitic in Australian marsupials. Three evolutionary lines are postulated for the radiation within the Herpetostrongylinae, each derived from a form resembling existing species of Woolleya Mawson, 1973, parasitic in Dasyuridae and Thylacinidae: (i) a short lineage restricted to Dasyuridae; (ii) Dasyuridae-Peramelidae and Myrmecobiidae, followed by re-invasion into Dasyuridae; (iii) Dasyuridae-Macropodidae-Potoroidae, Petauridae and Phalangeridea. W. hydromyos Mawson, 1973, and Paraustrostrongylus ratti Obendorf, 1979, are interpreted as secondary transfers of marsupial parasites to recent murid invaders. No evidence was found to support peramelid parasites giving rise to species parasitic in Diprotodontia. Herpetostrongylus and Vaucherus are considered as a distinct phylogenetic unit based on south-east Asia and parasitic in reptiles.