Progress and problems in the assessment of flower morphology in higher-level systematics
- First Online:
- Cite this article as:
- Endress, P.K. & Matthews, M.L. Plant Syst Evol (2012) 298: 257. doi:10.1007/s00606-011-0576-2
- 586 Downloads
Floral features used for characterization of higher-level angiosperm taxa (families, orders, and above) are assessed following a comparison of earlier (precladistic/premolecular) and current classifications. Cronquist (An integrated system of classification of flowering plants. Columbia University Press, New York, 1981) and APG (Angiosperm Phylogeny Group) (Bot J Linn Soc 161:105–121, 2009) were mainly used as the basis for this comparison. Although current circumscriptions of taxonomic groups (clades) are largely based on molecular markers, it is also important to morphologically characterize these new groups, as, in many cases, they are completely novel assemblages, especially at the level of orders and above. Features used in precladistic/premolecular classifications are often much more evolutionarily plastic than earlier assumed. A number of earlier neglected but potentially useful features at higher levels are discussed based on our own and other recent studies. As certain features tend to evolve repeatedly in a clade, it appears that apomorphic features in the strict sense are less helpful to characterize larger clades than earlier assumed, and rather apomorphic tendencies of features are more useful at this level.