Rattus
Rattus is a genus of muroid rodents, all typically called rats. However, the term rat can also be applied to rodent species outside of this genus.
Species and description
The best-known Rattus species are the black rat and the brown rat. The group is generally known as the Old World rats or true rats and originated in Asia. Rats are bigger than most Old World mice, which are their relatives, but seldom weigh over in the wild.Taxonomy of ''Rattus''
The genus Rattus is a member of the giant subfamily Murinae.The genus Rattus proper contains 64 extant species. A subgeneric breakdown of the species has been proposed, but does not include all species.