Pará spiny tree-rat
The Pará spiny tree rat or Surinam spiny tree rat, is a spiny rat species found in Brazil.
Previously, Mesomys Stimulax's karyotype was 2n=60, Fundamental number, FN=116. However more recently the new karyotype has been found to be 2n=60, FN=110. This points to the idea that this species is most likely a species complex.