This study explores the floral biology and reproduction mode of Ambrosina bassii L. that belongs to a monospecific genus of the subfamily Aroideae (Araceae). The species has a limited distribution and the number of mature plants within natural populations is low. Reproductive success of this species is limited due to low fructification and seed rates, however there is a positive relationship between the plant vigour and its investment to the reproduction. In stable habitats, there are more flowering plants than in newly colonized habitats, where the frequency of juvenile non-mature plants is higher. The knowledge of these biological and reproductive characters constitutes the first data useful for the preservation and the management of this rare, endangered and protected species on Corsica.