Extrafloral Nectaries of Some Australian Phyllodineous Acacias

Abstract

The extrafloral nectaries of 43 phyllodineous Acacia species in the sections Phyllodineae, Plurinerves and Juliflorae were examined; material was collected mainly in south-eastern Queensland. The nectaries were of three types: porate (30 species), non-porate (12 species) and flat (only Acacia macradenia). The structure and anatomy of each type are described, and relationships are established between nectary type and both infrageneric taxa and phyllode length. The belief that nectaries are absent from or rare in acacias from dry regions is not upheld.