The Paraguayan fat-tailed mouse opossum (''Thylamys macrurus'') is a species of

opossum Opossums () are members of the marsupial order Didelphimorphia () endemic to the Americas. The largest order of marsupials in the Western Hemisphere, it comprises 126 species in 18 genera. Opossums originated in South America and entered North A ...

in the family Didelphidae. It is found in forested areas of Brazil and Paraguay.

Description

It is known only from a few specimens. For two listed specimens, one had a head-and-body length of about 135 mm and a tail length of about 140 mm, while the other had a head-and-body length of about 120 mm and a tail length of about 155 mm. Most of its

fur A fur is a soft, thick growth of hair that covers the skin of almost all mammals. It consists of a combination of oily guard hair on top and thick underfur beneath. The guard hair keeps moisture from reaching the skin; the underfur acts as an ...

is gray, but the shoulder areas are reddish gray, and the

ventral Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

is pure white or creamy white. There is also a ring of black fur surrounding each

eye An eye is a sensory organ that allows an organism to perceive visual information. It detects light and converts it into electro-chemical impulses in neurons (neurones). It is part of an organism's visual system. In higher organisms, the ey ...

. The

surface of the tail is white. The

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fus ...

surface of the tail is gray for the first one third to one half of its length (going from the base to the tip); the remainder of the

surface of the tail is white. The tail is hairless except for about its first ten mm (going from the base to the tip). Although the genus Thylamys is characterized by fat storage in the tail, there is no evidence that this species stores fat in its tail.

References

Opossums Marsupials of Brazil Mammals of Paraguay Near threatened animals Near threatened biota of South America Mammals described in 1818 Taxa named by Ignaz von Olfers Taxonomy articles created by Polbot {{marsupial-stub