Oligoryzomys
Oligoryzomys is a genus of rodents in the tribe Oryzomyini of family Cricetidae. Many species are known as pygmy rice rats or colilargos. The genus is found from Mexico to Tierra del Fuego and includes approximately 17 species.

Yamil Hussein E. · CC BY-SA 3.0 · via Wikipedia/Commons. May be a photograph of a specimen, or an artist’s reconstruction — an interpretation of a skeleton, since colour and soft tissue are almost never preserved.
On record
Recorded, not inferred- Also called
- pygmy rice ratPBDB
- Sits inside
- SigmodontinaePBDB
- Diet
- herbivorePBDB, for Rodentia
- Life habit
- ground dwellingPBDB, for Rodentia
- Motility
- actively mobilePBDB, for Osteichthyes
- Environment
- terrestrialPBDB, for Eutheria
Time the record covers
At least 2.5 million years on record.
The record covers at least 2.58 Mya to 11.7 ka. No occurrence read is dated outside 3.6 Mya to 0 Mya.
14 occurrences of Oligoryzomys on record, most of them in the Pleistocene. The Paleobiology Database records this as a living group. Bar height is expected occurrences, not a count: each fossil is spread across the span it is dated to, so a tall narrow bar means tight dating and a low wide one means loose.
When
14 occurrences- Pliocene7%
- Pleistocene69%
- Holocene24%
These are dates about fossils, not the animal: the record can only begin after it arose and end before it died out, so either end may reach further. Shares are expected occurrences: a fossil dated to a span is counted partly in each period it straddles. More on what this infers.
Found in
3 formations
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The named rock units Oligoryzomys has been recovered from, largest first. Drawn where the rock is now, not where it formed. 10 occurrences have no formation on record, which is common for older literature.
Oligoryzomys and its relatives
PleistoceneWhere Oligoryzomys and its relatives were recorded in the Pleistocene.
Found in the same rock
218 taxa- Akodon6 sites
- Thylamys4 sites
- Calomys musculinus3 sites
- Ctenomys3 sites
- Desmodus3 sites
- Didelphidae3 sites
- Galea leucoblephara3 sites
- Gracilinanus3 sites
- Monodelphis domestica3 sites
- Necromys3 sites
- Oryzomyini3 sites
- Oryzomys3 sites
- Oxymycterus3 sites
- Proechimys3 sites
- Reithrodon auritus3 sites
- Sigmodontinae3 sites
- Sturnira3 sites
- Thrichomys3 sites
- Abrothrix2 sites
- Andinomys edax2 sites
- Calomys2 sites
- Calomys tener2 sites
- Carollia2 sites
- Carterodon sulcidens2 sites
The Paleobiology Database records 10 sites for Oligoryzomys, and this reads all of them. The number is how many of those sites it was catalogued from too. The 24 sharing the most are listed.
This is not a list of everything alive at the time. It is only what has come out of the same ground as this animal and been written down.
Entered from
11 references- Evolution of small mammal communities during the late Quaternary in a middle-altitude valley of Northwestern Argentina2
- Why are there no giants at the dwarves feet? Insular micromammals in the eastern Mediterranean2
- Fauna de mamíferos do Quaternário de Serra da Mesa (Goiás, Brasil)2
- Pliocene sigmodontine rodents (Mammalia: Cricetidae) in northernmost South America: test of biogeographic hypotheses and revised evolutionary scenarios1
- Síntesis actualizada del registro paleontológico pleistoceno en el Noroeste argentino1
- Small mammals taphonomy and environmental evolution during Late Pleistocene-Holocene in Monte Desert: The evidence of Gruta del Indio (central west Argentina)1
- Diversidade de pequenos mamíferos (Didelphimorphia e Rodentia) do Holoceno do nordeste do estado do Rio Grande do Sul, Brasil: implicações taxonômicas e paleo ambientais1
- Quaternary mammals from Serra do Bodoquena, Mato Grosso do Sul, Brazil1
- Sigmodontinos (Mammalia: Rodentia) del Pleistoceno tardío del valle de Tafí (Tucumán, Argentina): taxonomía, tafonomía y reconstrucción paleoambiental1
- A New Fossil Phyllotine (Rodentia: Muridae) from Northwestern Argentina and Relationships of Reithrodon Group1
- An Overview of Research at Cocha Cashu Biological Station1
Each of the 14 occurrences read was entered from one of these publications, ordered by how many each accounts for. This is not a search for papers mentioning the name. Entries link to doi.org where the Paleobiology Database holds an identifier, and to its own record where it does not. Relayed as the Paleobiology Database holds them, not checked against what they resolve to.
Media and terms
Media content2
Picture of Oligoryzomys
- Source
- Wikipedia/Commons
- Credit
- Yamil Hussein E.
- Licence
- CC BY-SA 3.0
- Commercial use
- the licence allows it
CT scan
- Source
- MorphoSource
- Licence
- not stated by the source
- Commercial use
- cannot be read from the licence given — check the record
- Specimen
- Oligoryzomys costaricensis · MSB:Mamm:MSB:Mamm:159847
Smithsonian Open Access was not reached for this taxon, so this list is what the others held rather than everything there is.
The description on this site
- Licence
- CC BY-SA 4.0
This is what the site found, which is not the same as what exists.
Keep going
What may have been alongside itSigmodontinae through timeFormations of the PleistoceneThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Bangs 1900