Ontogeny of the Calliandra - massulae (Mimosaceae : Ingeae), and the associated viscin body

摘要

Polyads, called also massulae, are common in the Mimosaceae. Within this family, only in Calliandra (s. 1.) polyads show a remarkable morphological variation: 16-grained lens-shaped massulae in the neotropical Zapoteca (syn. Calliandra p.p.), and highly asymmetric eight-grained massulae in Calliandra (s. str.). As a further specialisation the massulae in Calliandra (s. str.) possess a sticky appendage called a viscin body. The form and ontogeny of this unique two-dimensional construction of the massula is of particular interest. In Calliandra (s. str.) the octad is normally the developmental product of the initiation stage, beginning with one pollen mother cell (PMC). In total, Calliandra (s. str.) possesses eight PMCs in each anther.