Systematics and distribution of old world Mendoncia (Acanthaceae: Thunbergioideae)

A taxonomic treatment of the Paleotropical species in the genus Mendoncia is\ud presented in which ten species and one variety are recognized: M. bella, M. combretoides, M. cowanii, M. cowanii var. coursii, M. decaryi, M. delfina, M. flagellaris,\ud M. gilgiana, M. lindaviana, M. phytocrenoides, and M. vinciflora. Two are here described\ud as new to science. Mendoncia is one of five genera in the subfamily Thunbergioideae.\ud Recent molecular studies have shown that Mendoncia is monophyletic. The Paleotropical species form a basal grade from which the monophyletic Neotropical species are derived. Species of the genus consist of woody vines that occur in both Neotropical and Paleotropical wet forests. Paleotropical distribution is throughout tropical Africa, Madagascar, and Mayotte. Mendoncia is characterized by its drupaceous fruit, welldeveloped bracteoles, and climbing habit. Little is known about the ecology of these plants, including pollinators and modes of dispersal. The bracteoles of several species are filled with water that may protect the flowers while in bud and during anthesis. Field observations during this study revealed that flowers are visited by passerine birds and various insects. This is the first synthesis of the genus from throughout the Paleotropics