Terata of two legume species with radialized corolla: some correlations in floral symmetry

Abstract

Most papilionoid legumes (Leguminosae) are characterized by zygomorphic flowers. Features of monosymmetry are inherent to all floral whorls. We compare flowers of two species of papilionoid legumes with anomalously radialized corollas. Except for vexilloid mode of all five petals, these flowers were remarkable with their free androecium and (in case of Clitoria ternatea) actinomorphic calyx. The symmetry of the gynoecium remains unaltered. These correlations point at a strong interrelation between perianth and androecium symmetry control, possibly governed by the same genes. A review on floral symmetry in related papilionoid genera indicates that staminal fusion is only possible in case of a discernible adaxial petal (flag). This rule has some exceptions which contribute to the idea of independent recurrent origin of monosymmetry in different leguminous clades.