Not only is it one of the most distinctive caterpillars of the large Geometridae family of moths but it is also easily identified as an adult moth.
Even if never seen before it’s one of those caterpillars where it doesn’t require a great leap of the imagination to associate it with the adult Magpie Moth (see below).
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For more on Geometrid caterpillars
The bold colours suggest it may be one of several caterpillars that are distasteful to predators. See more on caterpillar survival strategies
The species is fairly common in most of the British Isles and although largely nocturnal may also be disturbed during the day.
The Magpie Moth shown right was attracted to light in our Falmouth garden in July 2011