AnimaliaHighest rank in taxonomy. Groups all life into domains: Animalia, Plantae, Fungi, etc.IUCN LCInternational Union for Conservation of Nature — the world authority on species extinction risk, using standardized criteria. — Least Concern — widespread and abundant; not at immediate risk of extinction.In ProgressCurrent stage of this record in the editorial review workflow. Recent Sighting
Melanomys caliginosus
Dusky Rice Rat
(Tomes, 1860)
Detailed Texts Multi-lang
A small-to-medium sized rodent with dark, dense, coarse fur and a tail shorter than its body length. It has a robust appearance adapted for ground-dwelling in humid environments.
Added by
Anonymous Curator
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Under Review
Last modified by
Julia Trouin
TaxonomyBiological classification ranks placing this species within the tree of life, from Kingdom down to Genus.
PhylumRank below Kingdom. Groups organisms sharing a fundamental body plan (e.g., Chordata = vertebrates and some invertebrates).Chordata
ClassRank below Phylum. Subdivides by structural traits (e.g., Mammalia, Aves, Reptilia, Insecta).Mammalia
OrderRank below Class. Groups related families sharing common ancestry (e.g., Carnivora, Primates).Rodentia
FamilyRank below Order. Groups closely related genera (e.g., Felidae = cats, Canidae = dogs).Cricetidae
GenusRank just above Species. The first word in the two-part binomial scientific name.Melanomys
Taxonomic AuthorityThe scientist who first formally described and published this species, followed by the year of publication.(Tomes, 1860)
Record Completeness
95%Coming soon
Ecology & StatusHow this species lives: habitat preferences, diet, behavior, population status, and role in its ecosystem.
OriginWhether the species is native (evolved here), endemic (found only here), or introduced by human activity.
Native
Population TrendDirection of change in population size over time: increasing, stable, decreasing, or unknown.
Stable
Breeding SeasonTime of year when this species typically reproduces or flowers.
Year Round
Trophic RolePosition in the food chain: producer, herbivore, carnivore, omnivore, decomposer, or parasite.
Omnivore
Recent SightingsWhether this species has been observed in the wild in Costa Rica within recent years.
Yes
Habitat SummaryOverview of the specific ecosystems and environments where this species is found in Costa Rica. Multi-lang
Inhabits moist lowland and montane forests, often near streams, forest edges, and disturbed areas in Central and South America.BehaviourDaily activity patterns, movement, territory use, foraging style, and seasonal behavioral changes. Multi-lang
Primarily terrestrial and nocturnal. They are active foragers on the forest floor, frequently moving through leaf litter.Social ActivitySocial structure: whether the species is solitary, paired, or colonial; hierarchy and communication. Multi-lang
Solitary behavior outside of the mating season.Feeding GuildWhat the species eats, how it forages or hunts, and its role as a consumer in the food web. Multi-lang
Terrestrial generalist omnivore.Trophic Chain DetailsSpecific interactions in local food webs: prey species, predators, competitors, and scavengers. Multi-lang
Omnivorous; diet includes seeds, fruits, fungi, and various small invertebrates. Preyed upon by owls and terrestrial snakes.Reproductive BehaviourMating strategies, courtship displays, nesting or spawning behavior, and parental care. Multi-lang
Typical cricetid reproduction; females can have multiple litters per year if conditions are favorable.Physical Measures
Length (cm)
9.0 - 13.0 cm
Weight (Grams)
30 g - 60 g
Offspring per cycleTypical number of young (live births, eggs, or seeds) produced by one adult in a single reproductive event or breeding season.2 - 6
Sexual DimorphismObservable physical differences between males and females of the same species (e.g., size, coloration, features).No
Lifespan
Sexual MaturityAge at which the individual becomes capable of reproducing for the first time.
3 - 5 Months
Gestation / IncubationDuration from fertilization to birth (mammals) or to hatching (egg-laying species).
20 - 25
Lifespan EstimatedExpected duration of life from birth to natural death under wild conditions.
Males1 - 2 Years
Females1 - 2 Years
Evolutionary AdaptationsInherited traits and behaviors that improve the species' survival and reproduction in its specific environment. Multi-lang
Possesses a dense, slightly water-repellent coat that helps maintain body temperature in humid and rainy conditions.
Main ThreatsDocumented pressures reducing the population: habitat loss, hunting, disease, climate change, and invasive species. Multi-lang
Threatened primarily by habitat loss and fragmentation resulting from deforestation and intensive land-use practices.
Interesting FactsSurprising or notable facts that highlight what makes this species unique or ecologically important. Multi-lang
Despite their name, they are not exclusively restricted to rice fields; they are versatile generalists in their native forest habitats.