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Oniscus asellus


Oniscus asellus is one of the largest native woodlice in Britain, at up to 16 mm (0.63 in) long.[3] It is relatively flat, and is a shiny grey in colour,[2] although juveniles are rougher.[3] Pale patches are often visible on the back of Oniscus asellus; these are areas that store calcium, which is then used to reinforce the exoskeleton after a moult.[3] Moulting occurs in two halves, with the rear half moulting before the front half. The exuvia is often consumed by the animal after moulting


Oniscus asellus is the most widespread species of woodlouse in the British Isles, both geographically and ecologically.[2] It is not known from the Mediterranean Basin, but is widespread in Northern and Western Europe, as far east as the Ukraine, as well as in the Azores and Madeira; it has also been widely introduced in the Americas.[


Oniscus asellus, the common woodlouse, is one of the largest and most common species of woodlouse in the British Isles and Western and Northern Europe, growing to lengths of 16 mm and widths of 6 mm

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1 Comment

Maria dB
Maria dB 8 years ago

nice series!

Spotted by

Heerlen, Limburg, Netherlands

Spotted on Oct 7, 2011
Submitted on Feb 19, 2012

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