This female Hairy-footed Flower Bee's legs appear to be covered in yellow Cowslip pollen. Cowslips flourish in my unmown lawn, which is a profusion of yellow at present.
She will be making a nest somewhere to lay her eggs, which will be threatened by the Common Mourning Bee, Melecta albifrons below.
Source: Field Guide to the Bees of Great Britain and Ireland by Steven Falk.
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