This family contains 13 species in 2 genera. Restricted to tropical parts of the New World, it includes some fairly common and sometimes conspicuous forest residents. It is an unfortunate and potentially confusing accident of taxonomy that agoutis do not belong to the family Agoutidae, which instead contains their relatives, the pacas.
Dasyproctids are moderately large, up to around 2 kg in weight. They have slender and graceful bodies supported by very thin and long legs. The hind limbs are notably longer than the forelimbs. The head is large, ears small and rounded but conspicuous, and eyes large. Four digits are found on each forefoot, but the fourth is reduced in size. The hind feet are 3-toed. All digits have sharp, hoof-like claws, and walking and running are digitigrade. Agoutis have a very short tail, while that of acouchis is longer.
The pelage of members of this family is coarse but has a distinct glossy sheen. The hairs over the rump are especially long. Their color varies from nearly black to yellowish brown on the back, with the underparts generally paler, and the long hairs over the rump may be contrastingly colored.
The skulls of agoutis and acouchis are more elongate and not nearly as robust as those of the related pacas. A sagittal crest may be present. The premaxillae and nasals project forward well beyond the incisors. The zygomatic arches are relatively delicate, without any trace of the expanded plate that characterizes pacas. The auditory bullae are not especially inflated, and paroccipital processes are of moderate size also. Dasyproctids are hystricognathous and hystricomorphous; the infraorbital canal is fairly large, and it lacks a separate groove for carrying nerves.
The dental formula of agoutis and acouchis is 1/1, 0/0, 1/1, 3/3 = 20. The cheekteeth of members of this family are hypsodont and flat-crowned. Their surface includes several re-entrant folds, which soon are isolated as islands as the teeth wear. Incisors are relatively delicate.
These animals are usually solitary, but they are occasionally seen in small groups around concentrations of food. They are generalist herbivores, consuming fruits, nuts, succulent plants, leaves, and even roots. They can be serious pests around peanut and cassava crops. Dasyproctids are fast and manueverable runners, resembling small antelope in some ecological and behavioral traits. Like pacas, they are treasured by hunters for their tender and mild flavored meat.
The fossil record of this family extends to the early Oligocene.
Families of Order Rodentia Suborder Sciurognathi Family Aplodontidae (mountain beaver, sewellel) Family Sciuridae (squirrels) Family Castoridae (beavers) Family Geomyidae (pocket gophers) Family Heteromyidae (kangaroo rats, pocket mice, and allies) Family Dipodidae (birch mice, jumping mice, jerboas) Family Muridae (familiar rates and other rodents) Family Anomaluridae (scaly-tailed squirrels) Family Pedetidae (spring hare, springhaas) Family Ctenodactylidae (gundis) Family Myoxidae (dormice and hazel mice) Suborder Hystricognathi Family Bathyergidae (mole rats, blesmols, and rats) Family Hystricidae (Old World porcupines) Family Petromuridae (rock rat or dassie rat) Family Thryonomyidae (cane rats or grasscutters) Family Erethizontidae (New World porcupines) Family Chinchillidae (Chinchillas and viscachas) Family Dinomyidae (pacarana, branick rats, false paca) Family Caviidae (cavies and guinea pigs) Family Hydrochaeridae (capybara) Family Dasyproctidae (agoutis, acouchis) Family Agoutidae (pacas) Family Ctenomyidae (tuco-tucos) Family Octodontidae (degus, coruros, rock rats) Family Abrocomidae (chinchilla rats, chinchillones) Family Echimyidae (spiny rats) Family Capromyidae (hutias, zagouties, cavies, Indian coneys) Family Heptaxodontidae (Quemi, giant hutias) Family Myocastoridae (nutria, coypu)
<<<<<<<>>>>>>>ARTIODACTYLA CARNIVORA CETACEA CHIROPTERA DASYUROMORPHIA DERMOPTERA DIDELPHIMORPHI DIPROTODONTIA HYRACOIDEA INSECTIVORA LAGOMORPHA MACROSCELIDEA MICROBIOTHERIA MONOTREMATA NOTORYCTEMORPHIA PAUCITUBERCULATA PERAMELEMORPHIA PERISSODACTYLA PHOLIDOTA PRIMATES PROBOSCIDEA RODENTIA SCANDENTIA SIRENIA TUBULIDENTATA XENARTHRA