Spalacidae

From Wikipedia, the free encyclopedia

iSpalacids
Fossil range: Early Miocene - Recent
Lesser Bamboo Rat, Cannomys badius
Lesser Bamboo Rat, Cannomys badius
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Rodentia
Superfamily: Muroidea
Family: Spalacidae
Gray, 1821
Subfamilies

Spalacinae
Myospalacinae
Rhizomyinae

Spalacidae is a family of rodents in the large and complex superfamily Muroidea. It includes blind mole rats, bamboo rats, root rats, and zokors. This family represents the oldest split (excluding perhaps the Platacanthomyinae) in the muroid superfamily, and is comprised of animals adapted to a subterranean way of life. It was thought that these rodents evolved adaptations to living underground independently until recent genetic studies demonstrated that they form a monophyletic group. Members of the Spalacidae are often placed in the family Muridae along with all other members of the Muroidea.

Norris et al. (2004) listed several characteristics that are present in all members of this family and that distinguish them from the rest of the muroids, (clade Eumuroida). These are "the reduction or absence of external eyes, reduced pinnae, stocky body, short tail (<50% head and body length), broad rostrum, triangular-shaped braincase, infraorbital canal ovoid shape and does not extend ventrally to the roof of the palate, zygomatic plate absent or much reduced, nasolacrimal canal inside infraorbital 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 the malleus bone."

The Spalacids are classified in 3 subfamilies, 6 genera and 30 species.

[edit] Subfamilies

[edit] 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.
  • Norris, R. W., K. Y. Zhou, C. Q. Zhou, G. Yang, C. W. Kilpatrick, and R. L. Honeycutt. 2004. The phylogenetic position of the zokors (Myospalacinae) and comments on the families of muroids (Rodentia). Molecular Phylogenetics and Evolution, 31:972-978.
  • 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.