Sigmodon hispidus

**Semantic type:** Mammal

**Definition:** From the Sigmodon genus of rodents, Sigmodon hispidus was the first animal model to be used in polio research. It has a stout body, small ears and a dark coat that can be dark brown or mixed buff and black, with a tail length that is 35% of its total body length. As its name suggests, this breed has a proclivity for cotton in its nesting, and is a natural Hanta viral reservoir.

**Synonyms:** - Hispid Cotton Rat