"Amblyrhiza" roughly translates to "blunt root", and "inundata" has been speculated to be in reference to Cope's disbelief that such a large rodent could evolve in an isolated region such as the islands of the northern Lesser Antilles.

[8] Amblyrhiza is currently considered to be a close relative of Elasmodontomys obliquus, a smaller yet similar rodent found in the Quaternary deposits of Puerto Rico.

Although it has yet to be decided exactly where Amblyrhiza fits in a phylogenetic context, it is thought that they belong to a paraphyletic group of giant caviomorphs known as Heptaxodontidae.

[7] Paleontology work began in the northeastern area of the Caribbean in the mid nineteenth century, when phosphate mining boomed in the region and fossils were coincidentally found in associated strata.

[9] The fossilized remains of this remarkably large rodent are found solely within Quaternary cave deposits, all of which are located on the islands of the northern Lesser Antilles, specifically Anguilla and St.