Nomada spp

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.

is a large genus of bees that parasitise Andrena spp. There are 97 species in France. They are rather wasp like in appearance, often being yellow and black, although there are quite a few red and black species and brown and black species.

Nomada fabriciana female, photographed in March and
identified by Christian Schmid-Egger of HymIS.
It is tremendously helpful with Nomada if you have noticed them trailing a potential host. If you can get a picture of both Nomada and its Andrena host you can probably get IDs for both, as each Nomada species only parasitises one (or occasionally a small number) of Andrena species.

To identify Nomada you need to be able to see:

1. The tegula (the joint at the wing base) - is it yellow or black?
2. The scutellum (the little separate lump on the end of the thorax in front of the abdomen) - how many yellow spots does it have?
3. The hairs on the underside of the hind femur - are they pressed against the leg, or standing up?
4. What combination of yellow, brown and black does the abdomen have (including the difficult to see area near the thorax).
5. Ideally, a full facial view to see what colour the labnum ('top lip') is.

Males are easier to identify than females.

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

Photographed by Loire Valley Nature:
Photos are numbered from left to right, top to bottom. 1-5 N. fabriciana female, in our orchard, March.

6 - 10 Nomada sp, April, Parc de Boussay.

11 Nomada sp, April, the Brenne.

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