Wasps appear to be the bane of summer picnics or hot days out in the garden, and yet they are a fascinating and diverse species of insect. Some wasps form complex and highly developed societies, whilst others are purely solitary. The wasp we tend to encounter and swat away is the Common Wasp (Vespula vulgaris), and out of all the species of wasp it is this one that has given wasps in general a bad and fearsome name. Wasps belong to the large insect order Hymenoptera, which also has the bees, ants and sawflies for company. Like bees, wasps are very important pollinators, and they also help to reduce pest species like caterpillars, flies and aphids. There are nearly 8,000 Hymenoptera species in the UK, and despite some of their annoyances to us, they play an important roll in a healthy and balanced ecosystem.
Family Vespidae (Social Wasps)
Family Crabronidae (Crabronid Wasps)
Family Ichneumonidae (Ichneumon Wasps)
Family Braconidae (Brachonid Wasps)
Family Gasteruptiidae (Gasteruptiid Wasps)
Family Eulophidae (Eulophid Wasps)
Family Chrysididae (Ruby-tailed Wasps)
Family Cynipidae (Gall Wasps)

Cynips quercusfolii

Neuroterus numismalis

Andricus foecundatrix

For further reference see the links below:
BWARS Bees, Wasps & Ants Recording Society
Facebook UK Bees, Wasps and Ants Group