What is this caterpillar?
QI am attaching a photo of a caterpillar I found on my geranium. I have never seen one like it before, so could you tell me what it is? Patricia Wyatt, via email
AThis is the larva of the vapourer moth (Orgyia antiqua). Widespread in Britain, it is frequently found in woodlands, hedgerows, parks and gardens.
Eggs are laid in July and August, but caterpillars don’t hatch until the following spring. After pupation, moths emerge in July and August.
Though caterpillars may nibble tender leaves and stems, they are not regarded as pests unless a colony feeds within a small area.
Female moths are virtually wingless and after mating they lay their eggs on the cocoons from which they emerge after pupating. The adult moth, which is foxy brown with two white spots, can be seen flying during the day.
This moth can be confused with the scarce vapourer (Orgyia recens), though this is rare and restricted to a few sites in north England and Scotland.