Nesomyinae
Encyclopedia
The Malagasy rats and mice are the sole members of the subfamily Nesomyinae. These animals are the only native rodent
s of Madagascar
, come in many shapes and sizes, and occupy a wide variety of ecological niche
s. There are nesomyines that resemble gerbil
s, rat
s, mice
, vole
s, and even rabbits. There are arboreal, terrestrial
, and semi-fossorial
varieties.
These rodent
s are clearly most closely related to some muroid rodents found on the Africa
n mainland. Some molecular phylogeneticists
consider this clade of Malagasy and African rodents to represent a distinct family, the Nesomyidae
. Other researchers place the Nesomyinae into a large family, Muridae
, along with all members of the superfamily Muroidea
.
It has been reported that the Nesomyinae is not monophyletic
, but this has not been supported in other analyses. Additionally, there were problems with this particular study, notably the use of Calomyscus as an outgroup
while more distantly related muroids
(rhyzomyines
) were included in the ingroup
. It seems likely that all rodent
s in Madagascar
are descendants from a single invasion of the island.
If monophyletic, the nesomyines represent one of only five colonization events of terrestrial mammals from mainland Africa. The other groups are tenrecs, lemur
s, Malagasy carnivorans, and bibymalagasians. Molecular clock
analyses suggest that the ancestor of the nesomyines colonized Madagascar about 20-25 million years ago. This is at approximately the same time as the Malagasy carnivorans, but is considerably more recent than the estimated colonization times of tenrecs and lemurs.
Nesomyinae contains 9 genera
and 27 species
.
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 of Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
, come in many shapes and sizes, and occupy a wide variety of ecological niche
Ecological niche
In ecology, a niche is a term describing the relational position of a species or population in its ecosystem to each other; e.g. a dolphin could potentially be in another ecological niche from one that travels in a different pod if the members of these pods utilize significantly different food...
s. There are nesomyines that resemble gerbil
Gerbil
A gerbil is a small mammal of the order Rodentia. Once known simply as "desert rats", the gerbil subfamily includes about 110 species of African, Indian, and Asian rodents, including sand rats and jirds, all of which are adapted to arid habitats...
s, rat
Rat
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, mice
Mouse
A mouse is a small mammal belonging to the order of rodents. The best known mouse species is the common house mouse . It is also a popular pet. In some places, certain kinds of field mice are also common. This rodent is eaten by large birds such as hawks and eagles...
, vole
Vole
A vole is a small rodent resembling a mouse but with a stouter body, a shorter hairy tail, a slightly rounder head, smaller ears and eyes, and differently formed molars . There are approximately 155 species of voles. They are sometimes known as meadow mice or field mice in North America...
s, and even rabbits. There are arboreal, 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...
, and semi-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...
varieties.
These rodent
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 are clearly most closely related to some muroid rodents found on the Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
n mainland. Some molecular phylogeneticists
Molecular phylogeny
Molecular phylogenetics is the analysis of hereditary molecular differences, mainly in DNA sequences, to gain information on an organism's evolutionary relationships. The result of a molecular phylogenetic analysis is expressed in a phylogenetic tree...
consider this clade of Malagasy and African rodents to represent a distinct family, the Nesomyidae
Nesomyidae
Nesomyidae is a family of African rodents in the large and complex superfamily Muroidea. It includes several subfamilies, all of which are native to either continental Africa or to Madagascar...
. Other researchers place the Nesomyinae into a large family, Muridae
Muridae
Muridae is the largest family of mammals. It contains over 600 species found naturally throughout Eurasia, Africa, and Australia. They have been introduced worldwide. The group includes true mice and rats, gerbils, and relatives....
, along with all members of the superfamily Muroidea
Muroidea
Muroidea is a large superfamily of rodents. It includes hamsters, gerbils, true mice and rats, and many other relatives. They occupy a vast variety of habitats on every continent except Antarctica. Some authorities have placed all members of this group into a single family, Muridae, due to...
.
It has been reported that the Nesomyinae is not monophyletic
Monophyly
In common cladistic usage, a monophyletic group is a taxon which forms a clade, meaning that it contains all the descendants of the possibly hypothetical closest common ancestor of the members of the group. The term is synonymous with the uncommon term holophyly...
, but this has not been supported in other analyses. Additionally, there were problems with this particular study, notably the use of Calomyscus as an outgroup
Outgroup
In cladistics or phylogenetics, an outgroup is a group of organisms that serves as a reference group for determination of the evolutionary relationship among three or more monophyletic groups of organisms....
while more distantly related muroids
Muroidea
Muroidea is a large superfamily of rodents. It includes hamsters, gerbils, true mice and rats, and many other relatives. They occupy a vast variety of habitats on every continent except Antarctica. Some authorities have placed all members of this group into a single family, Muridae, due to...
(rhyzomyines
Rhizomyinae
The subfamily Rhizomyinae of rodents includes the Asian bamboo rats and certain of the African mole rats. The subfamily is grouped with the Spalacinae and the Myospalacinae into a family of fossorial muroid rodents basal to the other Muroidea....
) were included in the ingroup
Ingroup
In sociology and social psychology, ingroups and outgroups are social groups to which an individual feels as though he or she belongs as a member, or to which they feel contempt, opposition, or a desire to compete. People tend to hold positive attitudes towards members of their own groups, a...
. It seems likely that all rodent
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 Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
are descendants from a single invasion of the island.
If monophyletic, the nesomyines represent one of only five colonization events of terrestrial mammals from mainland Africa. The other groups are tenrecs, lemur
Lemur
Lemurs are a clade of strepsirrhine primates endemic to the island of Madagascar. They are named after the lemures of Roman mythology due to the ghostly vocalizations, reflective eyes, and the nocturnal habits of some species...
s, Malagasy carnivorans, and bibymalagasians. Molecular clock
Molecular clock
The molecular clock is a technique in molecular evolution that uses fossil constraints and rates of molecular change to deduce the time in geologic history when two species or other taxa diverged. It is used to estimate the time of occurrence of events called speciation or radiation...
analyses suggest that the ancestor of the nesomyines colonized Madagascar about 20-25 million years ago. This is at approximately the same time as the Malagasy carnivorans, but is considerably more recent than the estimated colonization times of tenrecs and lemurs.
Nesomyinae contains 9 genera
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
and 27 species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
.
Taxonomy
Subfamily Nesomyinae - Malagasy rats and mice- Genus BrachytarsomysBrachytarsomysBrachytarsomys is a genus of rodent in the family Nesomyidae.It contains the following species:* White-tailed Antsangy * Brachytarsomys mahajambaensis * Hairy-tailed Antsangy...
- Malagasy white-tailed rats- White-tailed AntsangyWhite-tailed AntsangyThe White-tailed Antsangy is a species of rodent in the family Nesomyidae.It is found only in Madagascar....
, Brachytarsomys albicauda - Brachytarsomys mahajambaensisBrachytarsomys mahajambaensisBrachytarsomys mahajambaensis is an extinct rodent from northwestern Madagascar. It is known from nine isolated molars found in several sites during field work that started in 2001. First described in 2010, it is placed in the genus Brachytarsomys together with two larger living species, which may...
(extinct) - Hairy-tailed Antsangy, Brachytarsomys villosa
- White-tailed Antsangy
- Genus BrachyuromysBrachyuromysBrachyuromys is a genus of rodent in the family Nesomyidae.It contains the following species:* Betsileo Short-tailed Rat * Gregarious Short-tailed Rat...
- Malagasy short-tailed rats- Betsileo Short-tailed RatBetsileo Short-Tailed RatThe Betsileo Short-tailed Rat is a species of rodent in the Nesomyidae family.It is found only in Madagascar.Its natural habitats are subtropical or tropical dry forests and subtropical or tropical dry shrubland....
, Brachyuromys betsileoensis - Gregarious Short-tailed RatGregarious Short-Tailed RatThe Gregarious Short-tailed Rat is a species of rodent in the Nesomyidae family.It is found only in Madagascar.Its natural habitats are subtropical or tropical dry forests and subtropical or tropical dry shrubland....
, Brachyuromys ramirohitra
- Betsileo Short-tailed Rat
- Genus EliurusEliurusEliurus is a genus of rodent in the family Nesomyidae.It contains the following species:* Tsingy Tufted-tailed Rat * Ankarana Special Reserve Tufted-tailed Rat...
- Tufted-tailed rats- Tsingy Tufted-tailed Rat, Eliurus antsingy
- Ankarana Special Reserve Tufted-tailed Rat, Eliurus carletoni
- Ellerman's Tufted-tailed Rat, Eliurus ellermani
- Daniel's Tufted-tailed RatDaniel's Tufted-Tailed RatDaniel's Tufted-Tailed Rat is a species of rodent in the Nesomyidae family. It was discovered in 2003 in the Parc National de l’Isalo in south-central Madagascar...
, Eliurus danieli - Grandidier's Tufted-tailed Rat, Eliurus grandidieri
- Major's Tufted-tailed RatMajor's Tufted-Tailed RatMajor's Tufted-tailed Rat is a species of rodent in the Nesomyidae family.It is found only in Madagascar.Its natural habitat is subtropical or tropical dry forests....
, Eliurus majori - Lesser Tufted-tailed RatLesser Tufted-Tailed RatThe Lesser Tufted-tailed Rat is a species of rodent in the Nesomyidae family.It is found only in Madagascar.-References:* Baillie, J. 1996. . Downloaded on 19 July 2007....
, Eliurus minor - Dormouse Tufted-tailed RatDormouse Tufted-Tailed RatThe Dormouse Tufted-tailed Rat is a species of rodent in the Nesomyidae family.It is found only in Madagascar.-References:* Baillie, J. 1996. . Downloaded on 09 July 2007....
, Eliurus myoxinus - White-tipped Tufted-tailed RatWhite-tipped tufted-tailed ratThe White-tipped tufted-tailed rat is a rodent found only on the island of Madagascar. It is listed as a critically endangered species due to habitat loss.-References: Listed as Critically Endangered...
, Eliurus penicillatus - Petter's Tufted-tailed Rat, Eliurus petteri
- Tanala Tufted-tailed RatTanala Tufted-Tailed RatThe Tanala Tufted-tailed Rat is a species of rodent in the Nesomyidae family.It is found only in Madagascar.-References:* Baillie, J. 1996. . Downloaded on 19 July 2007....
, Eliurus tanala - Webb's Tufted-tailed RatWebb's Tufted-Tailed RatWebb's Tufted-tailed Rat is a species of rodent in the Nesomyidae family.It is found only in Madagascar.Its natural habitat is subtropical or tropical dry forests.It is threatened by habitat loss.-References:...
, Eliurus webbi
- Genus Gymnuromys
- VoalavoanalaVoalavoanalaThe Voalavoanala is a species of rodent in the family Nesomyidae. It is the only species in the genus Gymnuromys. It is found only in Madagascar. Its natural habitat is subtropical or tropical dry forests....
, Gymnuromys roberti
- Voalavoanala
- Genus Hypogeomys
- Votsovotsa (Malagasy Giant Rat), Hypogeomys antimena
- Hypogeomys australisHypogeomys australisHypogeomys australis is an extinct rodent from central and southeastern Madagascar. First described in 1903, it is larger than its close relative, the living Hypogeomys antimena, which occurs further west, but otherwise similar. Average length of the femur is 72.1 mm, compared to 63.8 mm...
(extinct)
- Genus MacrotarsomysMacrotarsomysMacrotarsomys is a genus of rodent in the family Nesomyidae.It contains the following species:Genus Macrotarsomys - Big-footed mice*Bastard Big-Footed Mouse, Macrotarsomys bastardi Milne-Edwards and G. Grandidier, 1898...
- Big-footed mice- Bastard Big-Footed MouseBastard Big-Footed MouseThe Bastard Big-footed Mouse is a species of rodent in the Nesomyidae family.It is found only in Madagascar.-References:* Baillie, J. 1996. . Downloaded on 19 July 2007....
, Macrotarsomys bastardi - Greater Big-Footed MouseGreater big-footed mouseThe Greater big-footed mouse is a nocturnal rodent found only on Madagascar. It is listed as a critically endangered species due to habitat loss.-External links:*...
, Macrotarsomys ingens - Macrotarsomys petteriMacrotarsomys petteriMacrotarsomys petteri, also known as Petter's Big-footed Mouse, is a Malagasy rodent in the genus Macrotarsomys. With a head and body length of 150 mm and body mass of 105 g , Macrotarsomys petteri is the largest species of its genus...
- Bastard Big-Footed Mouse
- Genus MonticolomysMonticolomysMonticolomys is a genus of rodents within the subfamily Nesomyinae of the family Nesomyidae, and is closely related to Macrotarsomys. The only species, Monticolomys koopmani, also known as the Malagasy Mountain Mouse or Koopman's Montane Voalavo, is found in the highlands of eastern Madagascar...
- Koopman's Montane Voalavo, Monticolomys koopmani
- Genus NesomysNesomysNesomys is a genus of rodent in the family Nesomyidae. It is found only on Madagascar, and contains the following species:* White-bellied Nesomys * Western Nesomys * Nesomys narindaensis †...
- White-bellied Nesomys, Nesomys audeberti
- Western Nesomys, Nesomys lambertoni
- Nesomys narindaensisNesomys narindaensisNesomys narindaensis is an extinct rodent that lived in northwestern Madagascar. It is known from subfossil skull bones and isolated molars found in several sites during field work that started in 2001. First described in 2010, it is placed in the genus Nesomys together with three smaller living...
(extinct) - Island MouseIsland MouseThe Island Mouse is a species of rodent in the Nesomyidae family.It is found only in Madagascar.-References:* Baillie, J. 1996. . Downloaded on 19 July 2007....
, Nesomys rufus
- Genus VoalavoVoalavoVoalavo is a genus of rodent in the subfamily Nesomyinae, found only in Madagascar. Two species are known, both of which occur in mountain forest above 1250 m altitude; Voalavo gymnocaudus lives in northern Madagascar and Voalavo antsahabensis is restricted to a small area in the central part...
- Eastern VoalavoEastern VoalavoVoalavo antsahabensis, also known as the Eastern Voalavo, is a rodent in the family Nesomyidae which occurs in the Anjozorobe forest of eastern Madagascar. Although surveys before 2002 failed to record the species, it is common in some places. However, it is threatened by habitat loss because of...
, Voalavo antsahabensis - Naked-tailed VoalavoNaked-tailed VoalavoVoalavo gymnocaudus, also known as the Northern Voalavo, Naked-tailed Voalavo, or just Voalavo, is a rodent in the family Nesomyidae found in the highlands of northern Madagascar. Discovered in 1994 and formally described in 1998, it is the type species of genus Voalavo; its closest relative is...
, Voalavo gymnocaudus
- Eastern Voalavo