The Atlantic spiny rats are all found in the genus ''Trinomys''. They are a group of

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

n spiny-rats in the family

Echimyidae Echimyidae is the family of neotropical spiny rats and their fossil relatives. This is the most species-rich family of hystricognath rodents. It is probably also the most ecologically diverse, with members ranging from fully arboreal to terres ...

Extant species of ''Trinomys''

Based on Natureserve.InfoNatura: Animals and Ecosystems of Latin America eb application 2007. Version 5.0 . Arlington, Virginia (USA): NatureServe. Available: http://www.natureserve.org/infonatura. The species of spiny rats in the genus ''Trinomys'' are apparently all Brazilian. In particular many of them are endemic to the

Atlantic Forest The Atlantic Forest ( pt, Mata Atlântica) is a South American forest that extends along the Atlantic coast of Brazil from Rio Grande do Norte state in the northeast to Rio Grande do Sul state in the south and inland as far as Paraguay and th ...

of southeastern Brazil. Not much is known for certain about their

ranges In the Hebrew Bible and in the Old Testament, the word ranges has two very different meanings. Leviticus In Leviticus 11:35, ranges probably means a cooking furnace for two or more pots, as the Hebrew word here is in the dual number; or perhaps ...

however, which still are being investigated, with frequent extensions to the recorded distributions of several species in various ecological classes of forest and dry land. They do not however appear to occur at high altitudes, and several of their ranges appear to be

parapatric In parapatric speciation, two subpopulations of a species evolve reproductive isolation from one another while continuing to exchange genes. This mode of speciation has three distinguishing characteristics: 1) mating occurs non-randomly, 2) gene ...

. Most species of ''Trinomys'' are terrestrial and ambulatory, though ''Trinomys yonenagae'' is unusual that it is semi-

fossorial A fossorial () animal is one adapted to digging which lives primarily, but not solely, underground. Some examples are badgers, naked mole-rats, clams, meerkats, and mole salamanders, as well as many beetles, wasps, and bees. Prehistoric eviden ...

, living in colonial burrows, and exhibits incipient specializations for

saltatorial This glossary of entomology describes terms used in the formal study of insect species by entomologists. A–C A synthetic chlorinated hydrocarbon insecticide, toxic to vertebrates. Though i ...

locomotion.

Phylogeny

Genus level

''Trinomys'' is the sister genus to the

genera ''Clyomys'' and ''Euryzygomatomys''. In turn, these three genera — forming the clade of

Euryzygomatomyinae Euryzygomatinae is a subfamily of rodents, proposed in 2017, and containing three extant genera of spiny Echimyidae: '' Clyomys'', '' Euryzygomatomys'', and ''Trinomys''. Members_of_this_echimyid_subfamily_all_share_an_origin_in_the_eastern_part ...

— share phylogenetic affinities with a clade containing ''

Carterodon Owl's spiny rat (''Carterodon sulcidens'') is a rodent species in the family Echimyidae found in Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and ...

'' and members of the family Capromyidae.

References

Trinomys Rodent genera Taxa named by Oldfield Thomas {{Echimyidae-stub