Phylogenetic analysis of the genus Tordylium (Tordylineae, Apioideae, Apiaceae) inferred from morphological data
8 October 2015
Koca, AsliTordylium is a medium sized genus characterized by an annual habit, 1-3 pinnate leaves, dorsally compressed mericarps, and thickened mericarp margins. Eighteen Tordylium species occur in Turkey, of which seven are endemic. Although the morphology of the genus is well known, evolutionary relationships among its species have never been evaluated. In this research, relationships within Tordylium are investigated using a parsimony analysis based on morphological features from 17 ingroup and 15 outgroup taxa from Turkey. Trees from the cladistic analysis indicate that Tordylium is paraphyletic due to the inclusion of Ormosciadium. The analysis suggests that Hasselquistia, Condylocarpus, and Ainsworthia are included in Tordylium, confirming their taxonomic treatments as synonyms. Within the paraphyletic Tordylium, two major clades are apparent, but these clades are not compatible with the current sub-generic classification. Tordylium lanatum, T. aegyptiacum, and T. elegans, which have dimorphic mericarps, form a monophyletic subclade. Finally, T. aegaeum should be accepted as a distinct species rather than a synonym of T. pestalozzae.