Sigmodon mascotensis (Rodentia: Cricetidae)

Abstract Sigmodon mascotensis Allen, 1897 is a cricetid commonly called the west Mexican cotton rat. From 1902 to 1969, it was designated a subspecies of S. hispidus after which, based on chromosomal and cranial characteristics, S. mascotensis was returned to species status. Dorsal pelage is brown and hispid, with ventral areas being whitish. This Mexican endemic rodent breeds throughout the year and inhabits tropical deciduous forest zones of western Mexico, mainly associated with grassy habitats. It is rare in tropical deciduous forest and abundant in grasslands and croplands. It prefers locations with higher percentages of ground cover in woody plants, forbs, and grasses, and lower in litter and bare ground. Preference is for more open and lower canopies. It is important prey for some carnivores, birds, and reptiles.