Geographic Range
Petaurillus hosei
(Hose’s Pygmy flying squirrel) is endemic to the eastern coast of Sarawak, on the
northwestern side of Borneo.
- Other Geographic Terms
- island endemic
Habitat
There was not any specific information found on the habitat of
P. hosei
but, as are most
flying squirrels
, Hose's pygmy flying squirrels are highly arboreal. These squirrels have only been
found in lowland forest types and are reported to use tree cavities as nest holes.
- Habitat Regions
- tropical
- terrestrial
- Terrestrial Biomes
- forest
- rainforest
Physical Description
Species in the genus
Petaurillus
are the smallest of the flying squirrels, with head and body length ranging from
68 to 89 mm and tail length from 62 to 98 mm. Hose's pygmy flying squirrels have large
eyes and ears. The body is similar to that of all
flying squirrels
, with a flat hairy tail and a gliding membrane that extends between the fore and
hindlimbs, called a patagium. Patagia increase the surface area of these squirrels,
enabling gliding. A cartilaginous extension of the wrist bones assists in spreading
the patagia.
Flying squirrels
have five digits on their hind limbs and four digits on their forelimbs, each digit
has a long claw at the end, which assists in climbing trees. Hose's pygmy flying squirrels
have dark dorsal fur and white ventral surfaces. They have a white spot behind each
ear and pale or buffy colored cheeks. The tail is brown with a white tip. The teeth
are not complex.
- Other Physical Features
- endothermic
- homoiothermic
- bilateral symmetry
Reproduction
The mating system of
P. hosei
is unknown. Mating systems in
flying squirrels
are generally not well understood, but it is likely that males and females do not
associate beyond a single breeding season.
Little is known about reproduction in Hose's pygmy flying squirrels. A close relative, Selangor pygmy flying squirrels ( P. kinlochii ), has a reported litter size of two. Females have 4 mammae, indicating a maximum litter size of 4. In other flying squirrels , breeding can occur multiple times during the breeding season, young are weaned within several months of birth, and reproductive maturity is acheived within a year of birth. Because Hose's pygmy flying squirrels live in lowland, tropical habitats, they may breed throughout the year.
- Key Reproductive Features
- iteroparous
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- viviparous
Hose's pygmy flying squirrel females nurse and care for their young, as do all female
mammals. They may be the sole caretakers of their young. Young are probably left in
a nest in a tree cavity until they are weaned and become independent.
- Parental Investment
-
pre-fertilization
- provisioning
-
protecting
- female
-
pre-hatching/birth
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- female
-
provisioning
Lifespan/Longevity
Information on the life span of
P. hosei
was not found but other, small flying squirrels may live to 5 to 6 years old in the
wild. Because of their body size, Hose's pygmy flying squirrels may have relatively
short lifespans.
Behavior
Little is known about behavior in Hose's pygmy flying squirrels.
Flying squirrels
, in general, are nocturnal animals that mostly stay in the trees. They travel by
scampering along branches and gliding between trees. Four individual Hose's pygmy
flying squirrels were reported to be found in the same nest cavity, suggesting that
there may be some sociality or that the individuals were a family group. These squirrels
are nocturnal
Home Range
The home range is unknown.
Communication and Perception
Like other aspects of the natural history of Hose's pygmy flying squirrels, there
is nothing known about social interactions. Other
flying squirrels
use sounds, chemical cues, and visual cues, such as movements with the tail, to communicate.
These flying squirrels, like others, are likely to have excellent night vision and
hearing that they use to navigate and avoid predation at night. They may have a keen
sense of smell to locate food items and to communicate.
Food Habits
No information was found on the diet of Hose’s pygmy flying squirrels. In general,
flying squirrels
eat seeds, fruits, and fungi. They may also take insects, bird eggs and nestlings,
and other small animals as they find them.
Predation
Predators of Hose's pygmy flying squirrels are unknown. Likely predators of these
small, nocturnal, arboreal mammals are nocturnal raptors, such as
owls
and arboreal snakes.
Ecosystem Roles
Because Hose's pygmy flying squirrels are likely to eat fruits, seeds, and fungi, they are likely to be important in dispersing tree seeds and fungal spores in their lowland, forest ecosystems.
- Ecosystem Impact
- disperses seeds
Economic Importance for Humans: Positive
Hose's pygmy flying squirrels, like other flying squirrels , are likely to impact seed and fungal spore dispersal in their native habitats through their feeding habits.
Economic Importance for Humans: Negative
There are no known adverse effects of P. hosei on humans.
Conservation Status
According to the IUCN’s red list of threatened species,
P. hosei
is listed as low risk, least concern.
Additional Links
Contributors
Tanya Dewey (author, editor), Animal Diversity Web.
- oriental
-
found in the oriental region of the world. In other words, India and southeast Asia.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- island endemic
-
animals that live only on an island or set of islands.
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- terrestrial
-
Living on the ground.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- 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.
- 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.
- 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.
- iteroparous
-
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- arboreal
-
Referring to an animal that lives in trees; tree-climbing.
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
References
Baillie, J. 2006. "IUCN" (On-line). 2006 IUCN Redlist of Threatened Species. Accessed November 30, 2006 at http://www.iucnredlist.org .
Eisenberg, J. 1989. The Mammals of the Neotropics, The Northern Neotropics . Chicago and London: The University of Chicago Press.
MacDonald, D. 1984. The Encyclopedia of Mammals . New York: Facts On File.
Nowak, R. 1999. Walker's Mammals of the World . Baltimore: The John Hopkins University Press.
Redford, K., J. Eisenberg. 1992. Mammals of the Neotropics, The Southern Cone . Chicago and London: The University of Chicago Press.
Wilson, D., D. Reeder. 1993. Mammal Species of The World . Washington District of Columbia: Smithsonian Institute.