''Microsciurus''
or dwarf squirrels is a
genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
of
squirrel
Squirrels are members of the family Sciuridae (), a family that includes small or medium-sized rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrel ...
s from the tropical regions of Central and South America.
Taxonomy and systematics
Recent
DNA
Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...
analysis has shown that there is some confusion regarding the traditional classification of the species in the genus ''Microsciurus'',
and that the genus may be
polyphyletic
A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies ...
.
Currently, there are four
species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
recognized:
*
Central American dwarf squirrel (''Microsciurus alfari'')
Allen, 1895, Costa Rica, Nicaragua, Panama, northern Colombia
*
Amazon dwarf squirrel (''Microsciurus flaviventer'')
Gray, 1867, western
Amazon basin
The Amazon basin is the part of South America drained by the Amazon River and its tributary, tributaries. The Amazon drainage basin covers an area of about , or about 35.5 percent of the South American continent. It is located in the countries ...
*
Western dwarf squirrel (''Microsciurus mimulus'')
Thomas, 1898, Ecuador, Colombia, Panama
*
Santander dwarf squirrel (''Microsciurus santanderensis'')
Hernández-Camacho, 1957, central Colombia
A 2020 paper published on the taxonomy of
Sciurinae split ''Microsciurus'' into three genera, one currently unnamed. The paper included genetic sampling from all species except
Santander dwarf squirrel and ''
(Microsciurus) simonsi''. It suggests several new species, not all described.
*''Microsciurus''
**
Central American dwarf squirrel, ''M. alfari''
**''Microsciurus "species 1"'' from Colombia
*''Leptosciurus''
**
Western dwarf squirrel, ''L. mimulus''
**
Andean squirrel, ''L. pucheranii'' (moved from ''
Sciurus
The genus ''Sciurus'' ( or ) contains most of the common, bushy-tailed squirrels in North America, Europe, Temperate zone, temperate Asia, Central America and South America.
Species
The number of species in the genus is subject to change.
In 200 ...
'')
**''
Leptosciurus similis''
**''
Leptosciurus otinus''
**''
Leptosciurnus boquetensis''
**''
Leptosciurus isthmius''
*''"Microsciurus"''
**
Amazon dwarf squirrel, ''"M." flaviventer''
**
"Microsciurus" sabanillae
**''"Microsciurus" "species 2"'' from Peru and Brazil (previously assigned to ''
Syntheosciurus
Bangs's mountain squirrel (''Syntheosciurus brochus'') is a poorly known species of tree squirrel, that only lives in Costa Rica and Panama. It can be found in mountain rain forests at an altitude between , and lives mainly in the tree tops, but ...
'')
Description
With a typical head-and-body length of about and a long tail, dwarf squirrels are relatively small. However, the
Neotropical pygmy squirrel, not in this genus, is much smaller than these species, as are certain squirrels in Africa and Asia. ''Microsciurus'' species have gray or brown backs, and white bellies.
Distribution and habitat
All dwarf squirrels in this genus live in
tropical rain forests. Estimates of their abundance are limited.
The IUCN lists the conservation status as "Least Concern" for three of the species and "Data Deficient" for ''
Microsciurus santanderensis''.
References
Bibliography
* Ronald M. Nowak: ''Walker's Mammals of the World''. Johns Hopkins University Press, 1999
{{Taxonbar, from=Q948353
Rodent genera
Rodents of Central America
Mammals of South America
Taxa named by Joel Asaph Allen