Gymnures, also called Hairy Hedgehogs or Moon Rats, are mammals belonging to the subfamily Hylomyinae, in the family Erinaceidae and the order Insectivora. Although more closely related to moles, they look like very large rats.
Although its closest relative is the hedgehog, full grown specimens more closely resemble large rats, or the North American opossum, (Didelphis virginianis), with which it shares similar habits and ecological niches (an example of parallel evolution).
The gymnure's body plan is believed to resemble that of the earliest mammals, with a large toothy head about 1/3rd the length of the total body, a naked furless tail for balance and thermoregulatory purposes, and a plantigrade stance.
They also have an outstanding sense of smell, and tactile response in the snout region. The related starnose moles have noses so innervated that they can readily detect and discern microscopic texture features.
Gymnures keep territories, and individuals are solitary except when breeding. The gymnure has a very strong scent, typically described as a rancid garlic or onion smell, which is produced by its territory marking scent glands. Several creatures similar in form and niche, such as the opossum and solenodon smell similar to the gymnure.