Moth pollination of the cryptic Cape orchid Monadenia ophrydea

Abstract

Summary Observations at a recently burnt site in the Western Cape Province, South Africa, showed that Monadenia ophrydea Lindl. is pollinated by settling moths. The pollinaria become attached to the ventral surface of the moth's proboscis when it is inserted into the nectar-containing spur. Moth pollination was not initially suspected in M. ophrydea as the flowers are dark beetroot-red, rather than white as found in classic moth-pollinated flowers. The dark-coloured inflorescences of those Monadenia species which flower solely after fire are cryptic among the charred and blackened branches of recently burnt vegetation, possibly to avoid detection by herbivores. The primary attractant to moths in M. ophrydea appears to be a strong cinnamon-like scent produced in the evening. Pollination occurred in over 90% of the flowers at the study site.