Phylogeny and a revised tribal classification of Menispermaceae (moonseed family) based on molecular and morphological data

The Menispermaceae, a largely tropical family of dioecious and predominantly climbing plants, have been the subject of various molecular studies that confirmed its monophyly and the para- and polyphyly of most of the currently recognized tribes. The newly recognized assemblages have been variously named informally in different studies. Here we present a comprehensive phylogenetic hypothesis of the Menispermaceae based on the analyses of three molecular markers (matK, trnL-F, ndhF) and 41 morphological characters for the most extensive taxonomic and geographic sampling of the family as compared to earlier studies. Phylogenetic relationships were inferred using maximum parsimony, maximum likelihood, and Bayesian approaches. Our results of the combined molecular and total-evidence datasets corroborate earlier findings, with an improved support for major clade contents. A new tribal classification of the Menispermaceae is proposed, in which nine clades are grouped within the subfamilies Chasmantheroideae and Menispermoideae, forming themselves two well-supported clades. Within the Chasmantheroideae, the two clades recovered are here recognized as tribes Burasaieae and Coscinieae; within the Menispermoideae the seven identified clades are recognized as tribes Anomospermeae, Cissampelideae, Limacieae, Menispermeae, Pachygoneae, Spirospermeae, and Tiliacoreae. Of these, Spirospermeae is newly described, while the names, if not the circumscriptions, of the remaining tribes are adopted from earlier treatments. The subfamilies and most tribes here identified are further diagnosed by unique combinations of morphological characters. A few genera not sampled for the molecular analysis are provisionally assigned to the recognized tribes based on their floral, fruit, endocarp, and seed features.