NATURAL HISTORY · CATALOGUE RECORD
Common Viscacha Rat
Octomys mimax Thomas, 1920
Source-backed taxonomic record
Accepted species in Catalogue of Life’s 11 September 2026 base release. This preserves the source classification and available supporting data; it is not a completed species monograph.
Open encyclopedia reference
The mountain viscacha rat or mountain vizcacha rat (Octomys mimax), historically viscacha rat or vizcacha rat, is a species of rodent in the family Octodontidae. It is endemic to Argentina.
It is the only living species within the genus Octomys. This diploid genus (2n = 56) may be ancestral to the two unusual suspected tetraploid species Tympanoctomys barrerae and Pipanacoctomys aureus. However, some genetic studies have rejected any polyploidism in mammals as unlikely, and suggests that amplification and dispersion of repetitive sequences best explain the large genome size.
Wikipedia contributors, Mountain viscacha rat; see linked history · CC BY-SA 4.0 . Plain-text lead excerpt, at most 180 words; no infobox or later sections Retrieved 2026-10-05T08:16:22.858973+00:00. This reference remains separate from the taxonomic record.
Identity & source status
- Scientific name
- Octomys mimax Thomas, 1920
- Name authority
- Thomas, 1920
- Common name
- Common Viscacha Rat
- Rank
- species
- Accepted status
- accepted
- Kingdom
- Animalia
- Phylum
- Chordata
- Class
- Mammalia
- Order
- Rodentia
- Family
- Octodontidae
- Genus
- Octomys
- Extinction status
- Recorded extant
Classification family tree
Nested taxonomic groups from the source. This is not a direct-ancestor chain, a dated evolutionary tree or a phylogenetic reconstruction.
- domainEukaryota (Chatton, 1925) Whittaker & Margulis, 1978
- kingdomAnimalia
- phylumChordata
- subphylumVertebrata
- infraphylumGnathostomata
- parvphylumOsteichthyes
- megaclassTetrapoda
- classMammalia Linnaeus, 1758
- subclassTheria Parker & Haswell, 1897
- infraclassEutheria Gill, 1872
- orderRodentia Bowdich, 1821
- suborderHystricomorpha Brandt, 1855
- infraorderHystricognathi Brandt, 1855
- familyOctodontidae Waterhouse, 1840
- genusOctomys Thomas, 1920
- speciesOctomys mimax Thomas, 1920
Close classified relatives
No other member of this genus is present in the selected snapshot.
Documented distribution
Source distribution statements, not a complete range map. A listed locality is not necessarily a place of origin.
Source literature & publication evidence
References attached to this source record, including nomenclatural citations where supplied. This is a selected bibliography; abbreviated citations remain in the source’s form.
- https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=584784 Source fields: Taxon.tsv dwc:namePublishedIn, Taxon.tsv dcterms:references
Origins, evidence & remaining research
Name authority and publication references document nomenclature where the source supplies it. They do not establish evolutionary origins or the earliest fossil occurrence.
Specimen-level evidence, morphology, ecological research, phylogenetic studies, a comprehensive bibliography and a located literary passage have not yet been compiled for this record. A suitable sourced image remains to be added.
Dataset citation & attribution
This exact taxon in ChecklistBank · Catalogue of Life 2026-09-11
Catalogue of Life 2026-09-11; dataset 316321; doi:10.48580/dgz5n. https://creativecommons.org/licenses/by/4.0/ . Retrieved 5 October 2026.
Stable key: col:48K7W. Classification follows source parent identifiers. English common names may vary by region.