Platacanthomyinae is the only subfamily in the family Platacanthomyidae. This subfamily of rodents includes the spiny dormice and the Chinese pygmy dormice. In spite of their appearance, these animals are not true dormice, but are part of the large and complex superfamily Muroidea. The platacanthomyines can be distinguished from the dormice, because they have no premolars giving them three cheek teeth like their relatives, the Muroidea.

The evolutionary relationship of the Platacanthomyinae to the rest of the Muroidea is very uncertain and they are most appropriately termed incertae sedis. This is the only subfamily of muroids that has not been included in a molecular phylogenetic study. They can be distinguished from both the family Spalacidae and the Eumuroida (all non-spalacid and non-platacanthomyine muroids) by the distinct shape of their infraorbital canal and by the presence of multiple openings in the palate of the skull. On the basis of these two characters, they have been considered to be distinct from all other muroids. More work is needed to determine the evolutionary position of this subfamily.

The Platacanthomyidae contains a single subfamily, two genera, and three species.

Taxonomy

• Family Platacanthomyidae
  • Subfamily Platacanthomyinae
    • Genus Platacanthomys (spiny dormouse)
      • Platacanthomys lasiurus (spiny dormouse)
    • Genus Typhlomys Pygmy dormice
      • Typhlomys cinereus (Chinese pygmy dormouse)
      • Typhlomys chapensis (Vietnamese pygmy dormouse)

References

• 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.

• Nowak, R. M. 1999. Walker's Mammals of the World, Vol. 2. Johns Hopkins University Press, London.

• 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.