Mason, Leafcutter and Orchard Bees Megachilidae

Bees are generally easy to identify to genus level using a simple wing venation based key (such as the FSC Aidgap Key to Bees, Ants and Wasps) if you have a specimen. They are not so easy to identify from photos or to species level.

If you can provide several good quality photos the experts on the HymIS and BWARS forums may be able to identify your Megachilidae, but many are difficult from photos.

Mason and Orchard Bees Osmia spp:
For information about some common Osmia species, see a post on Days on the Claise, with photographs of European Orchard Bee O. cornuta and Red Mason Bee O. rufa. For further information, with good photos and some great observations, see Bees in a French Garden.

European Orchard Bee Osmia cornuta
See post on Days on the Claise for further information, including photographs of male. Below, a female investigates the possibilities of drainage hole in our back door as a potential nest hole, April.

 

A male European Orchard Bee Osmia cornuta stakes out a nest hole on our back door. He has emerged a few days earlier than the females in order that he can be ready the moment they emerge. He identifies holes occupied by females close to emerging by scent, using his antennae. He can be identified as male by his white facial hairs.

Mason, Potter or Wool Carder Bees Anthidium spp:

 Anthidium spp are striking black and yellow bees, very active and fast moving and the males are aggressively protective of their territory, driving off all other insects (they are not threatening towards people though). There are a number of very similar species here. Like all Megachilids they collect pollen on special hairs on their bellies (clearly visible in the photo above). In some species the females also collect balls of fluff by scraping it off the undersides of vine leaves or from woolly plants such as Lambs Ears Stachys. The fluff is used to line nest holes. You can see a photo of a nest here, on Aigronne Valley Wildlife. Other species line the nest with pine resin. Unusually for a bee species, male Anthidiums are bigger than the females. Bees in a French Garden has a good entry on Anthidiums if you want further information.