Echinopsis ancistrophora group (Cactaceae):
Evolution of floral syndromes, floral scent variation and consequences for pollinators


In cooperation with
Dr. Robert Raguso, University of South Carolina, Columbia, USA
Dr. Lucinda McDade, Academy of Natural Sciences, Philadelphia, USA
Dr. Alicia Sersic & Dr. Andrea Cocucci, Córdoba, Argentina
A remarkable characteristic of the Andean Echinopsis ancistrophora group (Cactaceae) is the variety of combinations of floral traits found in different populations. According to the classic understanding of floral 'syndromes', some members of the E. ancistrophora group may be pollinated by hawkmoths (long, white flowers), others by bees (short, colorful flowers). However, all other possible combinations of characters are found in nature as well, from short, white diurnal flowers to pink and partly nocturnal flowers with 20 cm length, not fitting in the classic syndromes. These findings suggest ongoing adaptations to different pollinator groups in different mountain habitats.

In lab and field studies in 16 populations in Argentina and Bolivia the variation of floral morphology, nectar production, color, anthesis time and floral scent is studied, and the pollination biology of various flower morphs is investigated. The consequences of floral scent variation for potential pollinators are tested in the wind tunnel. Finally, a molecular phylogeny enables to infer the evolution of floral syndromes.
Echinopsis ancistrophora group (63,088 bytes)
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