Systematic relationships within the Litsea complex (Lauraceae): a cladistic analysis on the basis of morphological and leaf cuticle data

Abstract

The systematic relationships within the Litsea complex, consisting of Litsea, Lindera, Neolitsea, Actinodaphne, Dodecadenia, Iteadaphne, Parasassafras, Sinosassafras, Umbellularia and Laurus, are discussed. A cladistic analysis of morphological and leaf cuticle characters resulted in three most parsimonious trees, with Sassafras as sister group to other genera. The cladogram of only cuticular characters does not show clear relationships, but highlights the general integration of Litsea and Lindera. The cladograms show that most genera in the complex are polyphyletic. However, some monophyletic groups also appeared in the cladograms, such as Cylicodaphne–Cupuliformes characterised by a cup-shaped fruit cupule, Sinosassafras–Parasassafras by a minute involucral bracts, Uniumbellatae–Daphnidium by trinerved leaves and Litsea–Aperula by a racemiform inflorescence. Additionally, the cladistics results imply that some groups require further research.