Kiore.com

Kiore are the smallest and lightest of the three rats species we have most to do with.

There are three species of rats with whom humans have a close association. They are the Norway rat (Rattus norvegicus), black rat (Rattus rattus), and kiore (Rattus exulans). Kiore, at less than one third the body weight and two thirds the length of the Norway rat, is the smallest of the three. It must have been confused with a large mouse as one scientist named it Mus Exulans.

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Adults are 11 to 15 centimetres long from the nose to the base of the tail. The tail is about the same length as the body, and has rings like giant fingerprints that help it grip when climbing.

Two ways of telling them from other rats are that the feet have a dark patch on the outside of the hind feet near the ankle and female kiore have 8 nipples, while black rats have 10 and Norway rats 12.

The kiore has a pointy nose, large ears, a slender body, and small, delicate feet. The back hair is reddish brown with a much lighter underside.