Idiurus macrotislong-eared scaly-tailed flying squirrel

Geographic Range

Idiurus macrotis is native to southern Cameroon and Eastern Zaire, and the Bwamba forests in Uganda. (Rham, 1990)

Habitat

Idiurus macrotis inhabits dense tropical forests. This species is almost completely arboreal. Individuals spend days sleeping in the hollows of large trees and nights gliding from one tree to the next. (Nowak, 1997)

Physical Description

Idiurus macrotis is named for one of its remarkable characteristics, idios being Greek for ‘peculiar’ and oura meaning ‘tail’. The tail is longer than the head and body and is made feather-like in appearance by both long, widely spaced hairs and short, dense hairs that project laterally, almost perpendicular to the length of the tail. The hairless areas on the dorsal and ventral sides of the tail are scaly, and there are large horny scales present near the body. The tail may assist in gripping trees as well as balancing the animal.

The total length of I. macrotis is 208 to 220 mm and it weighs 25 to 35g. The pelage is short and dense and has a soft texture. The individual hairs are dark grey at the base and pale at the tips, with no patterns or color variation. The gliding membrane is also hairy. It extends between the hind- and forelimbs, with a small section connecting the wrist and neck and another enclosing a short portion of the tail and neck. The feet are covered with dark grey bristles and the claws are not very developed. The whiskers are long and black. (Julliot, et al., 1998; Kingdon, 1974; Nowak, 1997; Rham, 1990; Rosevear, 1969)

  • Sexual Dimorphism
  • male larger
  • Range mass
    25 to 35 g
    0.88 to 1.23 oz
  • Range length
    208 to 220 mm
    8.19 to 8.66 in
  • Average length
    208 mm
    8.19 in

Reproduction

Almost nothing is known about the reproduction of Idiurus macrotis. (Kingdon, 1974)

Almost nothing is known about their breeding habits. They have been captured and found to be pregnant in June and August. (Kingdon, 1974)

  • Key Reproductive Features
  • gonochoric/gonochoristic/dioecious (sexes separate)
  • sexual
  • viviparous

There is almost nothing known about the parental investment of Idiurus mactotis. It can be inferred that like all mammals, females nurse their young and therefore provide at least some care.

  • Parental Investment
  • pre-hatching/birth
    • provisioning
      • female
  • pre-weaning/fledging
    • provisioning
      • female

Lifespan/Longevity

The lifespan is not known. They cannot survive for any significant time in captivity. (Julliot, et al., 1998; Kingdon, 1974)

Behavior

Idiurus macrotis spend the day in colonies, clinging to the insides of hollow trees and sleeping. They may be found sharing a den with other species in the genus or some species of bats. They huddle together and are usually found in groups ranging from 2 to 40. They return to their specific den each night around 06.00 h. Dens have been observed to be inhabited for over three years. They leave the den one at a time between 18.15 and 19.00 h and stay on the den tree trunk for a half an hour before gliding to neighboring trees. They avoid leaving the trees. No kind of social interaction has been observed during the activity period. During the activity period, a translocated male was recorded as using an area seven acres large, averaging a distance of 790 m. (Julliot, et al., 1998)

Home Range

A male Idiurus macrotis that was tracked with a radio collar for 48 hours stayed within a three hectare area.

Communication and Perception

Idiurus macrotis produce a mouse-like squeak. Its primary function is not known. (Kingdon, 1974)

Food Habits

Stomach contents of specimens indicate that they are mostly frugivorous. Also, some bark peeling and ingestion of phloem sap has been observed, but little else is known about their feeding habits. (Julliot, et al., 1998)

  • Plant Foods
  • wood, bark, or stems
  • fruit
  • sap or other plant fluids

Ecosystem Roles

Little information is available on the impact this species has on its ecosystem. Idiurus macrotis may disperse the seeds of the fruit it eats, and may damage trees by eating bark.

  • Ecosystem Impact
  • disperses seeds

Conservation Status

Idiurus macrotis is considered a lower risk, but near threatened species on the IUCN redlist. Habitat loss due to deforestation is considered the largest threat to this species.

Contributors

Matthew Wund (editor), University of Michigan-Ann Arbor.

emily rudman (author), University of Michigan-Ann Arbor, Phil Myers (editor, instructor), Museum of Zoology, University of Michigan-Ann Arbor.

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

World Map

acoustic

uses sound to communicate

arboreal

Referring to an animal that lives in trees; tree-climbing.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

colonial

used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

frugivore

an animal that mainly eats fruit

herbivore

An animal that eats mainly plants or parts of plants.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

tactile

uses touch to communicate

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

References

Julliot, C., S. Cajani, A. Gautier-Hion. 1998. Anomalures (Rodentia, Anomaluridae) in Central Gabon : species conposition, population densities and ecology. Mammals, 62(1): 9-18.

Kingdon, J. 1974. East African mammals : an atlas of evolution in Africa IIB Hares and Rodents. London: Academic Press.

Nowak, R. 1997. "Walker's Mammals of the World Online" (On-line). Accessed January 11, 2004 at http://www.press.jhu.edu/books/walkers_mammals_of_the_world/rodentia/rodentia.anomaluridae.idiurus.html.

Rham, U. 1990. Scaly-Tailed Squirrel-Group Rodents. Pp. 118-125 in Griximek's encyclopedia of mammals, Vol. Vol 3. New York: McGraw-Hill.

Rosevear, D. 1969. Rodents of West Africa. London: British Museum of Natural History.