Bee Respnisble: The link between pollinators and wild orchids

The São Luís mountain in Arrabida was the chosen location for another meeting between LPN and Vileda Ibérica, as part of the Bee Responsible project - an Iberian project coordinated in Portugal by the Liga para a Protecção da Natureza (LPN) and by Ecocolmena in Spain.

In the heart of the Arrábida Natural Park, the group joined our guest guide, Armando Frazão - author of the field guide "Wild orchids of Arrábida" - to start a walking trail and get to know some of the wild orchids existing in the region and their intimate connection with the pollinators.

Although for most orchid species it is already too late to observe them in their flowering state, 12 species from 7 different genera were still identified:

Anacamptis

• Anacamptis pyramidalis

Cephalanthera

• Cephalanthera longifolia

Gennaria

• Gennaria diphylla

Himantoglossum

• Himantoglossum robertianum

Ophrys

• Ophrys apifera
• Ophrys speculum & Ophrys speculum subsp. lusitanica
• Ophrys sphegodes
• Ophrys scolopax subsp. apiformis
• Ophrys bomyliflora
• Ophrys lutea

Orchis

• Orchis italica

Serapias

• Serapias parviflora

Ophrys sphegodes

Serapias parviflora

Ophrys lutea

Ophrys bomyliflora

Ophrys scolopax subsp. apiformis

Cephalanthera longifólia

Ophrys apifera

In general, wild orchids are distinguished from other plants by having flowers with three sepals and three petals, grouped at the top of the stem, above the leaves and positioned in a more or less dense cluster. The central petal is differentiated from the others and is called the 'lip'.

They are extremely beautiful plants when observed up close. As well as having highly specialised floral parts, they stand out in the plant kingdom for their evolutionary strategies.

It is known that each species of orchid is pollinated by a restricted group of insects and in more specific cases by a single species of insect, as is the case with the Ophrys apifera which is pollinated exclusively bees of the apidae family.

In orchids, pollen is not free, but rather clumped together in a structure called pollinids. For the process of pollination to occur, these flowers need the visit of pollinators that "by mistake" carry the pollinids attached to their body until they visit other neighbouring plants.

What strategies do orchids use to attract pollinators?

The lip of flowers of the genus Ophrys mimics female insects of bees, wasps, flies and muskrats to thus attract the males. Because of this connection, some of the specific names of orchids come from the family of their pollinating insect.

As an example, we can make the following connection between pollinators and wild orchid species:

• Anacamptis pyramidalis - pollinated by beetles, bees and butterflies such as Thymelicus acteon.
• Orchis italica & Himantoglossum robertianum - pollinated by the terrestrial bumblebee (Bombus terrestris).
• Ophrys speculum - pollinated by the wasp of the species Dasyscolia ciliata.
• Ophrys lutea - pollinated by solitary bees belonging to the genus Anthophora sp..

It was a lesson in full learning about "Nature in miniature", the fascinating world of wild orchids and their great allies, the pollinators!

To all the group, our thanks for the good mood, sympathy and willingness to learn. Special thanks go to Armando Frazão for his enthusiasm and dedication to the subject and for his willingness to share knowledge.

A well-deserved rest at the end of the trail in the shade of this splendid Portuguese oak.