PETERMANNIOPSIS ANGLESEAENSIS GEN AND SP-NOV - AN AUSTRALIAN FOSSIL NET-VEINED MONOCOTYLEDON FROM EOCENE VICTORIA

A new species of fossil reticulate-veined monocot, Petermanniopsis ang leseansis gen. and sp. nov., is described from a mummified leaf base f rom the Anglesea Coal Deposit in Victoria, Australia. Cluster analysis and multidimensional scaling ordination of a range of leaf architectu ral and cuticular characters place it closest to the extant Australian monotypic and endemic Liliiflorae family Petermanniaceae from the tem perate rain forests of southeastern Queensland and northeastern New So uth Wales. In contrast, a parsimony analysis of this same data set fai led to resolve its position clearly within a clade representing the st rongly net-veined Dioscorealean taxa. Although the presence of a fossi l with affinities to the Petermanniaceae from Eocene Victoria supports the idea that the group represents an isolated member of the net-vein ed Liliiflorae autochthonous to Australia, this study also highlights the difficulty involved in assigning such fossils to modern monocot gr oups, or even distinguishing between these groups themselves, particul arly in cladistic studies using leaf architecture. Therefore, although most similar phenetically to the Petermanniaceae, the fossil is maint ained as incertae cedis affinis Petermanniaceae. Nevertheless, the pre sence of an Eocene Gondwanan net-veined monocot supports the thesis th at the group is an early evolutionary development in the evolution of the Liliiflorae.