Belgian Journal of Botany vol:127 issue:2 pages:157-170
In order to clarify the possible relationship between Adoxa and Sambucus, we studied the floral ontogeny of Adoxa moschatellina L. and Sambucus ebulus L. The following ontogenetical differences could be observed between both species: (1) a retardation in the development of the abaxial side of the lateral flowers of A. moschatellina; (2) the initiation of the corolla lobes of S. ebulus upon a ring-like extension and not directly on a flattened floral apex as in A. moschatellina; (3) the formation of a depression in the floral apex as the first step of the gynoecial development in S. ebulus, which was not observed in A. moschatellina. These differences are interpreted as variations of a same basic developmental pattern. Therefore, it is concluded that Adoxa evolved from an ancestor shared with Sambucus (or another Dipsacalean taxon). However, the possibility that the observed differences are the reflection of two different developmental patterns, is not completely ruled out.