Hoverflies – Masters of Mimicry? by Luke Wallace

Home , Cheilosia illustrata, Eupeodes, Helophilus pendulus, Hoverfly, Succisa pratensis, Volucella

To date, there have been 283 species many species, there is another and more of hoverfly identified in Britain. They striking evolutionary adaptation: mimicry. By are a fascinating group of flies that are mimicking the appearance and behaviour completely harmless to you or me, but you of the very predators that most insects fear, might not know that to look at them… namely bees, wasps and hornets, they are able to hide in plain sight. Adult hoverflies are not predatory and most feed on the nectar of flowering plants. They Over the months of June, July and have no ability to sting or bite, nor do they August 2015, 40 species of hoverfly were possess any armour to defend themselves. photographed and identified at Bedgebury. One attribute that is in their favour is flight. As Here are some of the species that were the name suggests, hoverflies exhibit extreme found in the Pinetum*, starting with two of agility when flying which means they are the less convincing mimics: able to avoid a lot of predators. However, for

LEFT: Eristalis intricarius – A large hoverfly with a furry appearance and colouration that is not a bad imitation of a bumblebee, but it does not really resemble any species particularly well.

RIGHT: Cheilosia illustrata – A rather poor imitation of a bumblebee, it has to be said. However, it is widespread and common.

*Please note, most hoverfly species do not have common names RIGHT: Volucella bombylans – A convincing mimic of the garden bumblebee Bombus hortorum, this species doesn’t just look like a bumblebee, its larvae actually live and develop in the nests of bumblebees!

MAIN IMAGE: Some hoverflies, such as this Chrysotoxum, appear almost identical to their mimic-hosts at a glance - a wasp in this case!

RIGHT: Volucella inanis – This hoverfly is one of the largest in the UK and does a good impression of a hornet, one of the most ferocious insect predators in our countryside. LEFT: Xylota segnis – This species does not look very similar to the species of sawfly it is trying to mimic. What it does do well is copy the behaviour of the sawflies, scuttling about from leaf to leaf. This species, and the similar Xylota sylvarum, are common in the Pinetum.

MAIN IMAGE: Helophilus pendulus - A colourful and common species in the Pinetum, seen here feeding on devils-bit scabious, Succisa pratensis.

So, next time you see a bee, wasp or hornet in the Pinetum, take a closer look because it could be a trick! To find out more about this fascinating group, ‘Britain’s Hoverflies: An Introduction to the Hoverflies of ABOVE: Sometimes, alas, being a skilled Britain’ by Ball and Morris is a great book. flyer and having a disguise is not always And don’t forget to check out our nature blog at enough to keep you safe, as this poor www.bedgeburypinetum.org.uk/pinetum for Eupeodes corollae found out. The predator all Bedgebury Pinetum’s wildlife sightings. is a species of Asilidae, also known as the Bedgebury’s fantastic biodiversity continues assassin fly! to prosper thanks to your continued interest and membership support.