Caring for Pollinators - Bundesamt für Naturschutz

Ssymank & Kearns Flies – Pollinators on two wings
2.4 Flies –Pollinators on two wings
by Axel Ssymank, Bonn & Carol Kearns, Santa Clara
1. Diptera as pollinators
Diptera, the true flies, are an important, but neglected group of pollinators. Diptera can be
distinguished from other insects by their two membranous front wings and the highly
reduced halteres that represent the remnants of the second pair of wings. They are an
ancient group, and were probably among the first pollinators of early flowering plants.
Fig. 1: Neoascia podacrica, a small
flower fly looking for nectar on a
Euphorbia-flower near a pond
margin.
Fig. 2: The drone-fly, Eristalis tenax, a
harmless flower fly pollinating a garden
Aster.
Fig. 3: Rhingia campestris, a flower
fly with a long snout concealing a
proboscis as long as its body sitting
on a Geranium-flower.
Many people think of flies as pests, and certainly there are many pest species. Fewer people
realize the beneficial activities provided by flies, including pest control, as food for valued
species such as birds and fish, as decomposers and soil conditioners, as water quality
indicators, and as pollinators of many plants.
Fig. 4: Anopheles mosquito,
known as vector for malariadisease.
Fig. 5: Chironomidae – midge
larvae
Fig. 6: Aphid-eating flower fly
larvae (Syrphus spec., Syrphidae)
At least seventy-one of the 150 (Evenhuis et al. 2008) Diptera families include flies that feed
at flowers as adults. More than 550 species of flowering plants are regularly visited by
Diptera (Larson et al. 2001) that are potential pollinations. Diptera have been documented to
be primary pollinators for many plant species, both wild and cultivated.
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