Family distributions in the Liliiflorae and their biogeographical implications

The Liliiflorae sensu Dahlgren, Clifford & Yeo (1985) represent ninety-one tribes in between forty-eight and fifty-six families and five orders worldwide, many of which are of restricted distribution, making them an ideal subject for biogeographic study. In order to evaluate the Liliiflorae's usefulness as phytogeographic indicators, Ecogeographic Pattern comparisons (EP) and Parsimony Area of Endemicity (PAE) analyses were applied to Takhtajan's (1969) biogeographic regions, using the Liliiflorae as characters. These procedures involved agglomerative clustering, multi-dimensional scaling and minimum spanning tree and parsimony analyses of the regions. The results indicate that the Liliiflorae have several centres of diversity: N and E Australia, the Cape and Madagascar and the SE Asian and Indian regions. Africa and India showed affinities with northern regions, whereas the southern Oceanian and Australasian regions were associated more with South America, although there were also links to Asia through the spread of both Laurasian and Gondwanan lily taxa into adjacent regions. The Liliiflorae show clear northern and southern taxon associations which may prove useful in the future for the re-evaluation of their past histories, as their traditional phylogenetic relationships are redefined radically by ongoing molecular systematic research.