Phylogeny of the tribe Antirrhineae (Scrophulariaceae) based on morphological and ndhF sequence data

Abstract

Phylogenetic relationships within the tribe Antirrhineae (Scrophulariaceae) are analysed and discussed on the basis of parsimony analyses of morphological and ndhF gene sequence data. The results indicate that the tribe Antirrhineae consists of four major groups of genera, the Anarrhinum clade, the Gambelia clade, the Maurandya clade, and the Antirrhinum clade. The Anarrhinum clade, consisting of the Old World bee-pollinated genera Anarrhinum and Kickxia, is sister to the rest of the tribe. The Gambelia clade consists of the New World genera Gambelia and Galvezia, which are very closely related and pollinated by hummingbirds. The Maurandya clade consists of one subclade including Maurandya and a number of related bee- or hummingbird-pollinated New World genera and another subclade with the Old World bee-pollinated genera Asarina and Cymbalaria. The Antirrhinum clade consists mainly of bee-pollinated Old World genera, such as Antirrhinum, Linaria, Chaenorhinum, and their segregates, but also includes the New World genera Mohavea and Howelliella, of which the latter is known to be partly pollinated by hummingbirds. It is concluded that hummingbird-pollination has evolved independently within Antirrhineae at least three times from bee-pollinated ancestors.