Pacas: Agoutidae

There are two species of paca: Agouti paca, commonly known as the paca, and Agouti taczanowskii, commonly known as the mountain paca. Though the genus name Agouti may be confusing, pacas and agoutis (family Dasyproctidae) are not in the same family. Pacas are among the largest of all rodents, with a head and body length of 20 to 30.5 inches (50 to 77.4 centimeters) and weight of 13.2 to 31 pounds (6 to 14 kilograms.) Their tail length is 5 to 9 inches (13 to 23 centimeters).

The paca resembles the mountain paca in most features, except the paca is slightly larger, has thinner and harsher fur, shorter nostrils, larger eyes, and thicker claws.

In both species, the upper body fur varies from reddish brown to dark chocolate or smoke-gray. There is a pattern of white or pale yellow irregular spots on the sides, arranged in rows of two to seven. The average number of rows is four. One or two upper rows are shorter and limited to the rear half of the body. Two or more middle rows run from the neck to the rump.