| Sciuromorpha Temporal range:Late Paleocene to Recent | |
|---|---|
 | |
| Ammospermophilus leucurus | |
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Rodentia |
| Suborder: | Sciuromorpha Brandt, 1855 |
| Families | |
†Allomyidae | |
Sciuromorpha (/sɪˈjuːrəmɔːrfə/ 'squirrel-like') is arodentsuborder that includes several rodentfamilies. It includes all members of theSciuridae (the squirrel family) as well as themountain beaver species.
Traditionally, the term has been defined on the basis of the shape of theinfraorbital canal. Asciuromorphouszygomasseteric system is characterized by attachment of the lateralmasseter muscle along the side of therostrum. Unlikehystricomorphous andmyomorphous rodents, the medial masseter muscle does not pass through the infraorbital canal. Among extant rodents, only the families Sciuridae,Castoridae,Heteromyidae, andGeomyidae are truly sciuromorphous. Some authorities would exclude the Geomyidae and Heteromyidae from that list due to the attachment of the medial masseter directly behind thezygomatic arch.[1]
Carleton and Musser (2005) redefined the rodent suborders onmorphological andmolecular grounds. They defined the Sciuromorpha as including three families, Sciuridae,Aplodontiidae, andGliridae. Of these, only the Sciuridae are truly sciuromorphous. The Aplodontiidae are protrogomorphous and the Gliridae are myomorphous. The connection between Aplodontiidae and Sciuridae has been proposed numerous times in the past. The two families have been united into a commoninfraorder (Sciurida) orsuperfamily (Sciuroidea). It has long been suggested thatdormice (Gliridae) are not particularly related to theMyomorpha, and theirzygomasseteric structure has been termed "pseudomyomorphy". The connection between squirrels and dormice has been almost exclusively suggested through genetic studies, and to a lesser degree via thefossil rodentReithroparamys.
Thesuborder Sciuromorpha contains 307 living species in 61 genera and three families. At least three extinct families are also recognised.
Data related toSciuromorpha at Wikispecies
