|Publication Type:||Journal Article|
|Year of Publication:||1993|
|Authors:||Posluszny, U., Charlton W. A.|
|Journal:||Aquatic BotanyAquatic Botany|
We propose a hypothesis for the derivation of flowers and reproductive structures in the Alismatidae (Helobiae) which is based on evolution of features of 'flower' and 'inflorescence' in different ways from an ancestral pre-floral condition with a multiaxial reproductive structure. We base this proposition on the existence of many cases of structures with attributes of both 'flower' and 'inflorescence'. In one suite of cases the lateral axes appear to have become flower-like while the main axis has become an inflorescence axis; in another the axes have become inflorescence-like proximally and flower-like distally. Like other evolutionary plans, it can also be read in the reverse direction, and would then imply that features of 'flower' and 'inflorescence' had become re-partitioned in different ways in the group. We interpret as reduced the simpler forms of flower among the group.