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.ApprovedCurrent stage of this record in the editorial review workflow. Recent Sighting
Microsciurus alfari
Alfaro's Pygmy Squirrel
Allen, 1895
Detailed Texts Multi-lang
An extremely small squirrel with dark brown dorsal fur and a lighter belly. Very difficult to observe due to its size and agility.
Added by
Anonymous Curator
Reviewed by
Julia Trouin
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).Sciuridae
GenusRank just above Species. The first word in the two-part binomial scientific name.Microsciurus
Taxonomic AuthorityThe scientist who first formally described and published this species, followed by the year of publication.Allen, 1895
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.
Herbivore
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 the mid to high strata of cloud forests and humid lowland tropical rainforests.BehaviourDaily activity patterns, movement, territory use, foraging style, and seasonal behavioral changes. Multi-lang
Herbivore: feeds on seeds, fruits, bark, and occasionally insects.Social ActivitySocial structure: whether the species is solitary, paired, or colonial; hierarchy and communication. Multi-lang
Mainly solitary, very cautious.Feeding GuildWhat the species eats, how it forages or hunts, and its role as a consumer in the food web. Multi-lang
Strictly arboreal, rarely descends to the ground.Trophic Chain DetailsSpecific interactions in local food webs: prey species, predators, competitors, and scavengers. Multi-lang
Primary consumer and seed disperser in the canopy.Reproductive BehaviourMating strategies, courtship displays, nesting or spawning behavior, and parental care. Multi-lang
Reproductive cycles linked to fruit availability.Physical Measures
Length (cm)
10.0 - 15.0 cm
Weight (Grams)
30 g - 50 g
Offspring per cycleTypical number of young (live births, eggs, or seeds) produced by one adult in a single reproductive event or breeding season.1 - 3
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.
1 Years
Gestation / IncubationDuration from fertilization to birth (mammals) or to hatching (egg-laying species).
40 - 45
Lifespan EstimatedExpected duration of life from birth to natural death under wild conditions.
Males3 - 5 Years
Females3 - 5 Years
Evolutionary AdaptationsInherited traits and behaviors that improve the species' survival and reproduction in its specific environment. Multi-lang
Reduced size and efficient camouflage that allow it to go unnoticed in the dense forest foliage.
Main ThreatsDocumented pressures reducing the population: habitat loss, hunting, disease, climate change, and invasive species. Multi-lang
Forest fragmentation and loss of arboreal connectivity in its distribution areas.
Interesting FactsSurprising or notable facts that highlight what makes this species unique or ecologically important. Multi-lang
Unlike other squirrels that are mostly diurnal, these can be active at various hours depending on forest cover.