Andalucia Life Fauna and Flora, Flowers of Andalucia Southern Spain

August 2007, Sawfly Orchid, Orphrys tenthredinifera

sawfly_orchid

The genus Orphrys is a large group of orchids with many subspecies. They are collectively referred to as Bee Orchids because the flowers of some species resemble the furry body of the bumble bee but there is far more to these orchids than that.

Each subspecies resembles a particular insect, a bee, wasp, beetle or, as in this case a sawfly and it is this insect that pollinates the orchid. The mimicry is even carried as far as the orchid producing the same scent as the receptive female insect. This scent is produced when there are active males about but no females. Males, attracted by the scent and visual appearance of the orchid, attempt to copulate with the flower. The pollen sticks to the head or body of the sawfly. As the sawfly moves between flowers the pollen orientates itself so that on arrival it can stick to the stigma of the new orchid. To ensure survival of orchids that most closely resemble the pollinating insect the duped male sawfly sulks and never returns to the same orchid. He may however visit an even more attractive sawfly orchid and be cheated again. Eventually the sawfly gets into such a huff that it will not visit another plant of the same subspecies. As a result only about 10% of an orchid population will be pollinated. This very selective pollination method means that the next generation will produce subspecies that are patterned just a little differently to the parent plants making identification of each subspecies quite difficult at times.

All Orphrys orchids are dormant underground tubers during the summer. In late summer and autumn a basal rosette of shiny, greenish blue leaves grow and in early spring the flower spike emerges carrying multiple flowers. This one was photographed at Grazalema.