A revision of the Malagasy endemic genus Chouxia Capuron (Sapindaceae)

A taxonomic revision of the Malagasy endemic genus Chouxia Capuron (Sapindaceae) is presented. CAPURON (1969) originally recognized a single, highly variable species (C. sorindeioides), providing a key to specimens based on indument and leaf size and shape. A careful reevaluation of these and other morphological characters (including leaflet number, venation, and inflorescence structure), and the availability of many new collections, allows the recognition of six species, five of which are described as new. Four of the novelties were known to CAPURON, and the fifth was first collected in 1994. One species occurs in dry deciduous forests in northern Madagascar, whereas all the others are restricted to humid forest in the northeastern part of the island, especially around the Bay of Antongil and N of Sambava. An emended description of the type species is provided to reflect the substantially revised circumscription adopted here.