CHROMOSOMAL REARRANGEMENTS IN ROCK WALLABIES, PETROGALE (MARSUPIALIA, MACROPODIDAE) .5. CHROMOSOMAL PHYLOGENY OF THE LATERALIS-PENICILLATA GROUP

Cladistic analysis of G-banded karyotypes was conducted on 11 Petrogale taxa from the lateralis/penicillata group with the genus Thylogale as an outgroup. Within the eastern Petrogale radiation (the penicillata complex), no homoplasy-free phylogenies could be generated and each tree contained character reversals, multiple origins and/or introgression of some chromosome characters. On the basis of the significance of some chromosome rearrangements and the genic relationships of taxa, one tree is favoured as being the most likely, although it is not the most parsimonious. In the lateralis/penicillata group the number of chromosome characters available was insufficient to accurately resolve the inter-relationships of the two complexes. However, the data are consistent with the eastern Petrogale radiation being a monophyletic group that excludes members of the Petrogale lateralis complex. The inter-relationships of the three subspecies of P. lateralis that were examined were not resolved by the chromosome data, although the karyotypes of both P. l. purpureicollis and P. l. 'Macdonnell Ranges' can be readily derived from that of P. l. lateralis.