Pollination of Two Species of Dalechampia (Euphoriaceae) in Mexico by Euglossine Bees

W. Scott Armbruster, University of California
Grady L. Webster, University of California


The large genus Dalechampia, including over 100 species of great vegitative diversity, has a basically uniform pseudanthial inflorescense. Investigation of two sympatric species is Mexico has shown considerable divergence in pollination adaptations. In D. spathulata, male euglossine bees are attracted by and collect aromatic substances secreted by the extra-floral glad of the inflorescences. In D. magnistipulata, female euglossine bees are attracted by and collect sticky resins secreted by the homologous gland. This study adds a new genus and family to the list of plant taxa exhibiting the male euglossine pollination syndrome which has been so well documented in tropical orchids. It also further elucidates a unique mode of pollinator attraction by resin production which has been reported from only one other plant genus.