Spiny rat
Encyclopedia
The spiny rats are a group of hystricognath rodent
s in the family Echimyidae. They are distributed from central Central America
through much of South America
. They were also found in the West Indies until the 19th century. Some authorities consider the nutria from southern and central South America to be a part of this family.
s, although they are more closely related to guinea pig
s and chinchilla
s. Most species have stiff pointed hairs, or spines
, that allow for protection.
Many echimyids can break off their tail
s when attacked. This action confuses predators long enough for the animal to escape. Unlike lizard
s, however, the tail of spiny rats does not regenerate
. This technique can obviously be used only once in each individual's lifetime.
Most spiny rats are rare and poorly known, but a few are extremely abundant. Terrestrial
, arboreal, and fossorial
members of this family exist. In general, the arboreal forms are most rat-like in appearance, whilst the burrowing species are more gopher
-like, with stocky bodies and short tails. Most species do not do well in conditions of high heat and arid
ity and are restricted to regions with an abundant source of water. They are almost exclusively herbivorous
.
The Thin-spined Porcupine, Chaetomys subspinosus, is often included in the Echimyidae due to similarities in the premolar
.
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
s in the family Echimyidae. They are distributed from central Central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
through much of South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
. They were also found in the West Indies until the 19th century. Some authorities consider the nutria from southern and central South America to be a part of this family.
Characteristics
In general form, most spiny rats resemble ratRat
Rats are various medium-sized, long-tailed rodents of the superfamily Muroidea. "True rats" are members of the genus Rattus, the most important of which to humans are the black rat, Rattus rattus, and the brown rat, Rattus norvegicus...
s, although they are more closely related to guinea pig
Guinea pig
The guinea pig , also called the cavy, is a species of rodent belonging to the family Caviidae and the genus Cavia. Despite their common name, these animals are not in the pig family, nor are they from Guinea...
s and chinchilla
Chinchilla
Chinchillas are crepuscular rodents, slightly larger and more robust than ground squirrels, and are native to the Andes mountains in South America. Along with their relatives, viscachas, they make up the family Chinchillidae....
s. Most species have stiff pointed hairs, or spines
Spine (zoology)
A spine is a hard, thorny or needle-like structure which occurs on various animals. Animals such as porcupines and sea urchins grow spines as a self-defense mechanism. Spines are often formed of keratin...
, that allow for protection.
Many echimyids can break off their tail
Tail
The tail is the section at the rear end of an animal's body; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammals, reptiles, and birds...
s when attacked. This action confuses predators long enough for the animal to escape. Unlike lizard
Lizard
Lizards are a widespread group of squamate reptiles, with nearly 3800 species, ranging across all continents except Antarctica as well as most oceanic island chains...
s, however, the tail of spiny rats does not regenerate
Regeneration (biology)
In biology, regeneration is the process of renewal, restoration, and growth that makes genomes, cells, organs, organisms, and ecosystems resilient to natural fluctuations or events that cause disturbance or damage. Every species is capable of regeneration, from bacteria to humans. At its most...
. This technique can obviously be used only once in each individual's lifetime.
Most spiny rats are rare and poorly known, but a few are extremely abundant. Terrestrial
Terrestrial animal
Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...
, arboreal, and fossorial
Fossorial
A fossorial organism is one that is adapted to digging and life underground such as the badger, the naked mole rat, and the mole salamanders Ambystomatidae...
members of this family exist. In general, the arboreal forms are most rat-like in appearance, whilst the burrowing species are more gopher
Gopher (animal)
The term gopher as it is commonly used does not relate to any one species, but is a generic term used to describe any of several small burrowing rodents endemic to North America, including the pocket gopher , also called true gophers, and the ground squirrel , including Richardson's ground squirrel...
-like, with stocky bodies and short tails. Most species do not do well in conditions of high heat and arid
Arid
A region is said to be arid when it is characterized by a severe lack of available water, to the extent of hindering or even preventing the growth and development of plant and animal life...
ity and are restricted to regions with an abundant source of water. They are almost exclusively herbivorous
Herbivore
Herbivores are organisms that are anatomically and physiologically adapted to eat plant-based foods. Herbivory is a form of consumption in which an organism principally eats autotrophs such as plants, algae and photosynthesizing bacteria. More generally, organisms that feed on autotrophs in...
.
The Thin-spined Porcupine, Chaetomys subspinosus, is often included in the Echimyidae due to similarities in the premolar
Premolar
The premolar teeth or bicuspids are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant, making eight premolars total in the mouth. They have at least two cusps. Premolars can be considered as a 'transitional tooth' during chewing, or...
.
Genera
- Family Echimyidae - spiny rats
- †Cercomys
- †Maruchito
- †Paulacoutomys
- †Willidewu
- Subfamily †Adelphomyinae
- †Adelphomys
- †Deseadomys
- †Paradelphomys
- †Stichomys
- †Xylechimys
- Subfamily Dactylomyinae
- DactylomysDactylomysDactylomys is the genus of South American bamboo rats or coro-coros. Coro-coros are arboreal members of the family Echimyidae. This genus contains three species....
- coro-coros - Kannabateomys - Rato de Taquara
- OlallamysOlallamysOlallamys is the genus of Andean soft-furred spiny rat that range from Panama through Colombia and Venezuela to northern Ecuador. These species are typically found at elevations above 2000 meters.*Genus Olallamys...
- Dactylomys
- Subfamily †Heteropsomyinae - extinct West Indian echimyids
- †BoromysBoromysBoromys is an extinct genus of Cuban rodents in the Echimyidae family.It contains the following species:* Oriente Cave Rat * Torre's Cave Rat...
- †BrotomysBrotomysBrotomys is an extinct genus of rodent in the Echimyidae family.It contains the following species:* Haitian Edible Rat * Hispaniolan Edible Rat...
- †Heteropsomys
- †Puertoricomys
- †Boromys
- Subfamily Eumysopinae
- †Acarechimys
- †Chasichimys
- †Eumysops
- Hoplomys Armored rat
- Lonchothrix
- MesomysMesomysMesomys is a genus of South American spiny rats in the family Echimyidae....
- †Palaeoechimys
- †Pampamys
- †Pattersomys
- †Protacaremys
- †Protadelphomys
- †Sallamys
- ProechimysProechimysProechimys is a genus of South American spiny rats of the family Echimyidae....
- spiny rats - ThrichomysThrichomysThrichomys is a South American rodent genus in the family Echimyidae. It contains three species, found in Bolivia, Brazil and Paraguay. They are as follows:* Common Punaré * Highlands Punaré...
- punaré - TrinomysTrinomysTrinomys is a genus of South American spiny rats in the family Echimyidae.- Extant species of Trinomys according to Natureserve :...
- Tribe Euryzygomatomyini
- Carterodon
- ClyomysClyomysClyomys is a South American rodent genus in the family Echimyidae. It contains two species, found in Brazil and Paraguay. They are as follows:* Bishop's Fossorial Spiny Rat * Broad-headed Spiny Rat...
- EuryzygomatomysEuryzygomatomysEuryzygomatomys is a South American rodent genus in the family Echimyidae. It contains two species, found in Argentina, Brazil and Paraguay. They are as follows:* Brandt's Guiara...
- guiara
- Subfamily Echimyinae
- Callistomys
- DiplomysDiplomysDiplomys is a genus of rodent in the Echimyidae family. They are found in Ecuador, Colombia and Panama.It contains the following species:* Arboreal Soft-furred Spiny Rat * Rufous Tree Rat...
- EchimysEchimysEchimys is a genus of spiny rat. Members of the genus are collectively called Spiny Tree-rats as they are arboreal and have pronounced spines.-Classification:The genus contains three extant species...
- arboreal spiny rats - IsothrixIsothrixThe toros or brush-tailed rats, genus Isothrix, are a group of spiny rats found in tropical South America, particularly in the Amazon Basin.-Description:...
- toros - MakalataMakalataMakalata is a genus of rodents in the family Echimyidae.It contains the following species:* Brazilian Spiny Tree Rat * Long-tailed Armored Tree-rat * Dusky Spiny Tree Rat...
- PattonomysPattonomysPattonomys is a genus of rodent in the Echimyidae family.It contains the following species:* Bare-tailed Armored Tree-rat * Speckled Spiny Tree-rat...
- PhyllomysPhyllomysPhyllomys is a genus of arboreal spiny rat, geographically restricted to the forests of eastern Brazil . There are thirteen named species in the genus...
- Santamartamys
- Toromys