Androniscus dentiger, the rosy woodlouse or pink woodlouse is a species of woodlouse found from the British Isles to North Africa.

Description

A. dentiger is a small woodlouse, at only 6 mm (¼ in) long, and is characteristically pink or orange in colour, with a yellow stripe along the midline of the dorsal surface, which divides in two towards the animal's tail. It has large eyes for its size and a granular exoskeleton.

Ecology

In the British Isles, A. dentiger is found in a wide variety of habitats, including coastal areas, gardens, old quarries and caves. It lives where there is a significant amount of lime available, and is reported to show a preference for Anglican churchyards over Catholic ones because the older, Protestant churches used ox-blood mortar. In the south of its range, A. dentiger is primarily troglobitic, with populations in different cave systems being genetically isolated by the lack of migration between caves. Animals like A. dentiger which prefer to live in caves, but are not restricted to the cave environment may be termed troglophilic. In North America, A. dentiger is only known to occur in greenhouses.

Subspecies

According to some authors, A. dentiger may be considered a complex of sibling species or cryptic species. Six subspecies are recognised: