Resurrection of Talbotia as a monotypic genus in Velloziaceae

Abstract

The recognition of Talbotia as a separate genus has been controversial for over 150 years. We have consolidated information available in the literature and added much information that we have gained in the field and from examination of many cultivated specimens. We have compiled a list of 32 characters from the literature and our observations that clearly differentiate Talbotia from Xerophyta and another six characters where there is a small amount of overlap between Talbotia and a minority of species of Xerophyta. Although there are molecular-based phylogenies available for African Velloziaceae, they either include few species or are based on only a single gene region. In the first case, Talbotia is sister to all five included taxa of Xerophyta and in the second case, Talbotia appears to be related to the shrubby species of Xerophyta rather than the herbaceous ones. This may indicate that further investigation based on more species and more gene regions may reveal that additional genera should be recognised to appropriately reflect the relationships between Old World Velloziaceae. In the meanwhile, we are resurrecting Talbotia as this would not render Xerophyta poly- or paraphyletic and so that the large number of differences between Talbotia and Xerophyta are not obscured by its combination with Xerophyta.