NATURAL HISTORY · CATALOGUE RECORD
Buff-bellied Fat-tailed Mouse Opossum
Thylamys venustus (Thomas, 1902)
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 buff-bellied fat-tailed mouse opossum (Thylamys venustus) is a species of opossum in the family Didelphidae. It is found in the transitional and humid forests of northern Argentina and southern Bolivia. Its dorsal fur is cinnamon brown. Most of its ventral fur is gray-based, but its chest, throat, and the thoracic midline (the midline of the thorax, which ranges from the throat to the top of the abdomen) are not gray-based. The postorbital ridges are absent in the young and weakly developed in adults. Initially classed as a Marmosa elegans subspecies, it was subsequently raised to species status in 1933. There are four synonyms: Marmosa elegans venusta (Thomas, 1902, Cochabamba), Marmosa elegans cinderella (Thomas, 1902, Tucumán Province), Marmosa elegans sponsoria (Thomas, 1921, Jujuy Province) and Marmosa janetta (Thomas, 1926, Tarija Department) with cinderella and sponsoria actually being one taxon and a subspecies of venustus; janetta is the largest of all and has cream-white ventral fur with plumbeous bases.
Wikipedia contributors, Buff-bellied fat-tailed mouse opossum; see linked history · CC BY-SA 4.0 . Plain-text lead excerpt, at most 180 words; no infobox or later sections Retrieved 2026-10-05T13:17:10.211457+00:00. This reference remains separate from the taxonomic record.
Identity & source status
- Scientific name
- Thylamys venustus (Thomas, 1902)
- Name authority
- (Thomas, 1902)
- Common name
- Buff-bellied Fat-tailed Mouse Opossum
- Rank
- species
- Accepted status
- accepted
- Kingdom
- Animalia
- Phylum
- Chordata
- Class
- Mammalia
- Order
- Didelphimorphia
- Family
- Didelphidae
- Genus
- Thylamys
- 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
- infraclassMetatheria Huxley, 1880
- orderDidelphimorphia Gill, 1872
- familyDidelphidae Gray, 1821
- subfamilyDidelphinae Gray, 1821
- tribeThylamyini Hershkovitz, 1992
- genusThylamys Gray, 1843
- speciesThylamys venustus (Thomas, 1902)
Close classified relatives
These entries share the source’s genus, Thylamys. They are not necessarily the closest relatives established by molecular evidence.
| Species | Classification | Source status |
|---|---|---|
| Dwarf Fat-tailed Mouse OpossumThylamys velutinus (Wagner, 1842) | DidelphidaeChordata | Accepted speciesRecorded extant |
| Mesopotamian Fat-tailed OpossumThylamys citellus (Thomas, 1912) | DidelphidaeChordata | Accepted speciesRecorded extant |
| Elegant Fat-tailed Mouse OpossumThylamys elegans (Waterhouse, 1839) | DidelphidaeChordata | Accepted speciesRecorded extant |
| Karimi's Fat-tailed Mouse OpossumThylamys karimii (Petter, 1968) | DidelphidaeChordata | Accepted speciesRecorded extant |
| Pallid Fat-tailed OpossumThylamys pallidior (Thomas, 1902) | DidelphidaeChordata | Accepted speciesRecorded extant |
| Argentine Fat-tailed Mouse OpossumThylamys sponsorius (Thomas, 1921) | DidelphidaeChordata | Accepted speciesRecorded extant |
| Tate's Fat-tailed Mouse OpossumThylamys tatei (Handley, 1957) | DidelphidaeChordata | Accepted speciesRecorded extant |
Names & synonyms
Names explicitly linked to this accepted taxon in the source. Synonymy can change with revision.
| Recorded name | Source status |
|---|---|
| Marmosa elegans venusta Thomas, 1902 Thomas, 1902 | synonym |
| Thylamys cinderella (Thomas, 1902) (Thomas, 1902) | synonym |
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=709384 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:56Q6J. Classification follows source parent identifiers. English common names may vary by region.