The Old World rats and mice, part of the subfamily Murinae in the family Muridae, comprise at least 519 species. Members of this subfamily are called murines. In terms of species richness, this subfamily is larger than all mammal families except the Cricetidae and Muridae, and is larger than all mammal orders except the and the remainder of the .
Description
The Murinae are native to
Africa,
Europe,
Asia, and
Australia. They are terrestrial
placental . They have also been
invasive species to all continents except
Antarctica, and are serious pest animals. This is particularly true in island communities where they have contributed to the
endangered and
of many native animals.
Two prominent murine species have become vital laboratory animals: the brown rat and house mouse are both used as medical subjects.
The murines have a distinctive molar pattern that involves three rows of cusps instead of two, the primitive pattern seen most frequently in .
Fossils
The first known appearance of the Murinae in the
fossil record is about
Miocene with the fossil genus
Antemus.
Antemus is thought to derive directly from
Potwarmus, which has a more primitive tooth pattern. Likewise, two genera,
Progonomys and
Karnimata, are thought to derive directly from
Antemus.
Progonomys is thought to be the ancestor of
Mus and relatives, while
Karnimata was previously thought to lead to
Rattus and relatives, although it is now thought to be a member of the extant tribe
Praomyini.
All of these fossils are found in the well-preserved and easily dated
Siwalik fossil beds of
Pakistan. The transition from
Potwarmus to
Antemus to
Progonomys and
Karnimata is considered an excellent example of
anagenesis.
Taxonomy
Most of the Murinae have been poorly studied. Some genera have been grouped, such as the hydromyine water rats, conilurine or pseudomyine Australian mice, or the phloeomyine
forms. It appears as if genera from Southeast Asian islands and Australia may be early offshoots compared to mainland forms. The
in the genera
Otomys and
Parotomys are often placed in a separate subfamily, Otomyinae, but have been shown to be closely related to African murines in spite of their uniqueness.
Three genera, Uranomys, Lophuromys, and Acomys, were once considered to be murines, but were found to be more closely related to Gerbillinae through molecular phylogenetics. They have been assigned a new subfamily status, Deomyinae.
Molecular phylogenetic studies of Murinae include Lecompte, et al. (2008), which analyzes African murine species based on the mitochondrial cytochrome b gene and two nuclear gene fragments. Lecompte, et al. (2008) estimates that African murines colonized Africa from Asia approximately 11 million years ago during the Miocene.
The following phylogeny of 16 Murinae genus, based on molecular phylogenetic analysis of the Interphotoreceptor Retinoid Binding Protein (IRBP) gene, is from Jansa & Weksler (2004: 264).
Distribution
The following is a list of Murinae genus divisions ordered by the continents that they are endemic to. Most of the diversity is located in
Southeast Asia and
Australasia.
-
Africa
-
Aethomys division – 1 genus
-
Arvicanthis division – 6 genera
-
Colomys division – 3 genera
-
Dasymys division – 8 genera
-
Hybomys division – 3 genera
-
Malacomys division – 1 genus
-
Oenomys division – 5 genea
-
Otomyini division/tribe – 3 genera
-
Eurasia
-
Apodemus division – 2 genera
-
Micromys division – 6 genera
-
Genus Mus
-
South Asia
-
Golunda division – 1 genus
-
Millardia division – 4 genera
-
Southeast Asia
-
Dacnomys division – 8 genera
-
Hadromys division – 1 genus
-
Maxomys division – 1 genus
-
Pithecheir division – 6 genera
-
Rattus division – 21 genera
-
Philippines
-
Chrotomys division – 5 genera
-
Crunomys division – 2 genera
-
Phloeomys division – 4 genera
-
Genus Musseromys
-
Sulawesi
-
Crunomys division – 2 genera
-
Echiothrix division – 1 genus
-
Melasmothrix division – 2 genera
-
Moluccas
-
Halmaheramys division – 1 genus
-
New Guinea
-
Hydromys division – 6 genera
-
Lorentzimys division – 1 genus
-
Pogonomys division – 11 genera
-
Uromys division – 5 genera
-
Xeromys division – 3 genera
-
Genus Mirzamys
-
Australia
-
Pseudomys division – 8 genera
List of species
As of 2005, the Murinae contained 129 genera in 584 species. Musser and Carleton (2005) divided the Murinae into 29 genus divisions. They treated the
Otomyinae as a separate subfamily, but all molecular analyses conducted to date have supported their inclusion in the Murinae as relatives of African genera. In a recent expedition in the Philippines, seven more
Apomys mice were added and the genus was proposed to split into two subgenera -
Apomys and
Megapomys, based on morphological and
cytochrome b DNA sequences. In 2021, a major revision was taken of
Praomyini.
The tribes are based on the classification by the American Society of Mammalogists.
SUBFAMILY MURINAE - Old World rats and mice
Notes
