Chrotomys

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Chrotomys Fossil range: None
Chrotomys whiteheadi
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Rodentia Family: Muridae Subfamily: Murinae Genus: Chrotomys Thomas, 1895
Species
Chrotomys whiteheadi Chrotomys mindorensis Chrotomys gonzalesi Chrotomys silaceus Chrotomys sibuyanensis

The genus Chrotomys contain a unique group of rodents found only in the Philippines, specifically the islands Luzon, Mindoro, and Sibuyan. Instead of being predominantly herbivorous or omnivorous like other murines, these rats feed predominantly on invertebrates although they do eat some vegetable matter. This vermivory is probably the result of a rat-like animal moving into an ecological niche usually filled by shrews. Shrews and other insectivores are absent on these Philippine islands.

Contents 1 Taxonomy 2 Species 2.1 Relationships as inferred by cytochrome b 2.2 Relationships as inferred by morphology 3 References

[edit] Taxonomy

Rickart et al. (2005) found that C. mindorensis, C. whiteheadi, and C. gonzalesi are closely related whereas C. silaceus and C. sibuyanensis represent earlier offshoots of the genus. Several authors place C. silaceus in the genus Celaenomys, but Rickart et al. (2005) suggest that neither genetic nor morphometric distance warrant it.

These rats are considered "old endemics" and are probably the result of one of the first colonisations of the Philippine islands. Other murines colonised the islands at a later time and are more closely related to mainland murines.

[edit] Species

• Chrotomys whiteheadi: Luzon Montane Shrew Rat
• Chrotomys mindorensis: Lowland Striped Shrew-Rat
• Chrotomys gonzalesi: Isarog Shrew-Rat
• Chrotomys silaceus: Silver Earth Rat
• Chrotomys sibuyanensis:

[edit] Relationships as inferred by cytochrome b

Chrotomys	Chrotomys silaceus Chrotomys sibuyanensis Chrotomys gonzalesi Chrotomys whiteheadi

[edit] Relationships as inferred by morphology

Chrotomys	Chrotomys sibuyanensis Chrotomys silaceus Chrotomys gonzalesi Chrotomys midorensis Chrotomys whiteheadi

[edit] References

• Nowak, R.M. 1999. Walker's Mammals of the World, Vol. 2. Johns Hopkins University Press, London.
• Rickart, E. A., L. R. Heaney, S. M. Goodman, and S. Jansa. 2005. Review of the Philippine genera Chrotomys and Celaenomys (Murinae) and description of a new species. Journal of Mammalogy, 86:415-428.