Towards a phylogenetic classification of the Ocotea complex (Lauraceae): an analysis with emphasis on the Old World taxa and description of the new genus Kuloa

Abstract

Abstract Ocotea is one of the largest genera in the Lauraceae (c. 400 spp.), and it has been known to be paraphyletic with respect to most other genera of the New World Lauraceae for almost 20 years. In the traditional circumscription, Ocotea contains not only Neotropical species, but also about 45 species from the African region, including Macaronesia, Madagascar, and the Comoro and Mascarene Islands. Only a few of the species have been included in previous molecular systematic analyses. Here we present a phylogenetic analysis, based on ITS and psbA-trnH sequences of 168 Lauraceae species, including 151 taxa from the Ocotea complex, among them 26 of the 45 Palaeotropical species currently placed in Ocotea. Our results show that the Old World species belong to two well-supported and morphologically distinguishable clades, one of which is placed unresolved among the Neotropical clades of the Ocotea complex, whereas the other is sister to Cinnamomum section Cinnamomum. The two clades can also be differentiated based morphologically. As a step towards a phylogenetic classification, we recognize the second group as the new genus Kuloa.