Common woodlouse

Description:

The woodlouse has a shell-like exoskeleton, which it must progressively shed as it grows. The moult takes place in two stages; the back half is lost first, followed two or three days later by the front. This method of moulting is different from that of most arthropods, which shed their cuticle in a single process. Metabolic rate is temperature-dependent in woodlice. In contrast to mammals and birds, invertebrates are not "self heating": the external environmental temperature relates directly to their rate of respiration.

Habitat:

Though today found worldwide, woodlouse populations in the Americas arrived from Europe by sea alongside humans.

Notes:

Spotted in my backyard