- Spalacidae
Taxobox
name = Spalacids
fossil_range = EarlyMiocene - Recent
image_caption = Lesser Bamboo Rat, "Cannomys badius "
image_width = 250px
regnum =Animal ia
phylum =Chordata
classis =Mammal ia
ordo =Rodent ia
superfamilia =Muroidea
familia = Spalacidae
familia_authority = Gray, 1821
subdivision_ranks = Subfamilies
subdivision =Spalacinae Myospalacinae Rhizomyinae The Spalacidae, or spalacids are a family ofrodent s in the large and complexsuperfamily Muroidea . They are native to easternAsia , theHorn of Africa , theMiddle East , and south-easternEurope . It includes theblind mole rat s,bamboo rat s, root rats, andzokor s. This family represents the oldest split (excluding perhaps thePlatacanthomyinae ) in the muroid superfamily, and comprises animals adapted to a way of life. It was thought that these rodents evolved adaptations to living underground independently until recent genetic studies demonstrated that they form amonophyletic group. Members of the Spalacidae are often placed in the familyMuridae along with all other members of the Muroidea.Characteristics
Spalacids are
mouse torat sized rodents, adapted to burrowing and living underground. They have short limbs, wedge-shaped skulls, strong neck muscles, largeincisor teeth, and small eyes and external ears. In the zokors, which dig primarily with their feet, rather than their teeth, the frontclaw s are also massively enlarged. These features are least extreme in the bamboo rats, which spend at least some of their time above ground, foraging for food. They are most highly developed in the blind mole rats, whose eyes are completely covered by skin, and entirely lack external ears or tails.All of the spalacid species dig extensive underground burrows, which may include storage chambers for food,
latrine chambers, breeding nests, and so on. They are generally solitary animals, and do not share their tunnel complexes with other individuals. All the species areherbivore s, feeding onroot s, bulbs, andtuber s.They give birth to litters of up to six young after a
gestation period of between three and seven weeks, depending on the species. As with many other muroids, the young are born blind, hairless, and helpless. They may stay with the mother for several months before setting off to establish their own burrows, although some species disperse as soon as they are weanedcite book |editor=Macdonald, D.|author= Corbet, Gordon|year=1984 |title= The Encyclopedia of Mammals|publisher= Facts on File|location=New York|pages= 666-671|isbn= 0-87196-871-1] .Technical Characters
Norris "et al."cite journal | author = Norris, R.W. "et al." | year = 2004 | title = The phylogenetic position of the zokors (Myospalacinae) and comments on the families of muroids (Rodentia)| journal = Molecular Phylogenetics and Evolution | volume = 31 |pages = 972–978 | doi = 10.1016/j.ympev.2003.10.020] listed several characteristics that are present in all members of this family and that distinguish them from the rest of the muroids, (the
clade Eumuroida ). These are "the reduction or absence of external eyes, reduced pinnae, stocky body, short tail (<50% head and body length), broadrostrum , triangular-shaped braincase,infraorbital canal ovoid shape and does not extendventral ly to the roof of thepalate ,zygomatic plate absent or much reduced, nasolacrimal canal insideinfraorbital canal , incisive foramina small to medium-sized, extensive neck musculature and prominent points of attachment on the occipitum, minimal reduction in M3 relative to M1 and M2, and a distinct orientation of the manubrium of themalleus bone."Classification
The Spalacids are classified in three subfamilies, six genera, and 30
species .Family: Spalacidae
*SubfamilyMyospalacinae , (zokor s)
*SubfamilyRhizomyinae , (root rats andbamboo rat s)
*SubfamilySpalacinae , (blind mole rat s)References
*Jansa, S. A. and M. Weksler. 2004. Phylogeny of muroid rodents: relationships within and among major lineages as determined by IRBP
gene sequences. Molecular Phylogenetics and Evolution, 31:256-276.*Michaux, J., A. Reyes, and F. Catzeflis. 2001. Evolutionary history of the most speciose mammals: molecular phylogeny of muroid rodents. Molecular Biology and Evolution, 17:280-293.
*Steppan, S. J., R. A. Adkins, and J. Anderson. 2004. Phylogeny and
divergence date estimates of rapid radiations in muroid rodents based on multiple nuclear genes. Systematic Biology, 53:533-553.
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