Large Yellow Underwing Moth Noctua pronuba
One of the most common large moths. Night-flying but often disturbed by day.
Wingspan 45-60mm; UK flight time Jun-Oct.
Showing the beautiful yellow underwings
Daytime - saved from drowning in birdbath - clear markings
Daytime - individual with dark markings
The yellow under-wings again
The markings are quite variable but the oval and kidney spots can usually be made out even on the darkest moths.
The moth under the wings
Night photo
Links:
Large Yellow Underwing caterpillar
Large Yellow Underwing eggs
Lesser Yellow Underwing moth