Revisiting the gynoecium of Cabralea canjerana and the concept of syncarpy in some species of the clade Melioideae

A reanalysis of the gynoecium of Cabralea canjerana was performed, and compared with floral studies of Guarea kunthiana, Guarea macrophylla, Trichilia catigua, Trichilia elegans and Trichilia pallida, all species belonging to the clade Melioideae. Our study structurally emphasizes the compitum and eusyncarpy. Floral buds and flowers were investigated according to usual techniques in light microscopy and scanning electron microscopy. Cabralea canjerana has a discoid stigma, pollen tube transmitting tract only in the lower part of the style, and a semi-inferior ovary with five carpels and locules and two ovules per locule with axile placentation. Guarea and Trichilia species have discoid and capitate stigmas, respectively, superior ovary, four carpels and locules in the former and three in the latter, two ovules per locule and axile placentation. Both genera have a transmitting tract along the length of the style. Cabralea canjerana and the other species are eusyncarpous, with compitum on the style and upper portion of the ovary.