Rhinophylla pumiliodwarf little fruit bat

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Geographic Range

Rhinophylla pumilio occurs in the Amazon Basin and the Guianas (Emmons, 1990). It can be found in Bolivia, Brazil, Venezuela, Ecuador, Columbia, French Guiana, Guyana, Suriname, and Peru (Rinehart and Kunz, 2006). (Emmons, 1990; Rinehart and Kunz, 2006)

Habitat

In Venezuela, R. pumilio is associated with moist areas and structured, tropical evergreen forests (Eisenberg and Redford, 1999). In French Guiana and southeastern Brazil, R. pumilio is found in primary and mature secondary lowland forest. In Amazonian Brazil R. pumilio is found in a wide variety of habitats including primary forest, forest fragments, and savannas. (Eisenberg and Redford, 1999; Rinehart and Kunz, 2006)

  • Range elevation
    10 to 1,400 m
    32.81 to ft

Physical Description

Rhinophylla pumilio is commonly known as dwarf little fruit bats or Peter's little fruit bats. Females are slightly larger than males with an average weight of 10.4 g in females and 9.4 g in males. Fur color is unicolored gray or brown to the base with slightly darker hair tips (Emmons, 1990). Head to body length averages 50 mm in females and 48.3 mm in males (Eisenberg and Redford, 1999). Wing color is dark to blackish, contrasting with the lighter metacarpals and phalanges (Rinehart and Kunz, 2006). Average forearm length in females is 35 mm and 34.7 mm in males. Average hind foot length for females is 10.77 mm and 10.33 mm in males. The ears are rounded, shorter than the head, and are a pinkish brown color (Rinehart and Kunz, 2006). Average ear length for females is 15.81 mm and 16.33 mm in males (Eisenberg and Redford, 1999). The tragus extends one-third of the length of the ear and is small and broad. (Eisenberg and Redford, 1999; Emmons, 1990; Rinehart and Kunz, 2006)

Dwarf little fruit bats have no external tail. The calcar is 5 mm in length and is distinct. The noseleaf is well developed, with a length twice its width. The tragus can reach well beyond the eye to the center of the forehead when flattened. (Rinehart and Kunz, 2006)

The dental formula is i 2/2, c 1/1, p 2/2, m 3/3, totaling 32 teeth. The medial upper incisors are notched and are larger than the outer incisors. The lower incisors contrast in size, the medial being larger and having a trilobed cutting edge . The two lower premolars are similar in form to the 3 lower molars. (Rinehart and Kunz, 2006)

Rhinophylla pumilio can be distinguished from Carollia species by the absence of a tail and reduced uropatagium. Rhinophylla pumilio can also be distinguished from other Rhinophylla species by incisor shape. The upper medial incisor is notched on cutting edge of R. pumilio and R. fischerae, whereas the cutting edge is uninterrupted in R. alethina. Rhinophylla pumilio also has a distinct lateral cingular style which is absent in R. fischerae and R. alethina. Rhinophylla pumilio is distinguished from other Rhinophylla species by the absence of conspicuous, stiff hairs along the distal edge of the uropatagium and a shorter calcar. (Rinehart and Kunz, 2006)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    7 to 13 g
    0.25 to 0.46 oz
  • Range length
    43 to 58 mm
    1.69 to 2.28 in
  • Average basal metabolic rate
    1.96ml cm3.O2/g/hr

Reproduction

The mating system of R. pumilio has not been studied in detail. Dwarf little fruit bats have been found roosting in groups of one male to two to three females, suggesting polygyny. (Rinehart and Kunz, 2006)

There is little available information on the reproductive behavior of R. pumilio. Pregnant and lactating females have been captured in March, May, June, July, August, September November, and December (Rinehart and Kunz 2006). As in other bat species, females give birth to one young per year. (Rinehart and Kunz, 2006)

  • Breeding interval
    Dwarf little fruit bats breed once yearly.
  • Average number of offspring
    1

There is little available information on the parental involvement of Rhinophylla pumilio. However, as in all bat species, females invest a significant proportion of their energy into gestation and lactation of their single offspring each year.

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

Lifespan/Longevity

Life expectancy of Rhinophylla pumilio is not known.

Behavior

Dwarf little fruit bats are sedentary, tent-making bats. They create tent-like structures for roosting from large leaves by biting the supporting structures of the leaf until they fold. They have been known to also roost in abandoned leaf tents made by other tent-making bats. Dwarf little fruit bats use tents as night feeding roosts and as daytime roosts. They change roosts every few days. Roosts often consist of one male and about three females. Tents are constructed approximately 1.5 m to 15 m above the ground. These bats have also been known to roost in culverts and thatched roofs. Dwarf little fruit bats are active immediately after dust and before dawn with a period of inactivity in the depths of the night (Rinehart and Kunz, 2006). (Rinehart and Kunz, 2006)

  • Range territory size
    1,600 m to 4,750 m km^2

Home Range

Rhinophylla pumilio can cover a distance of about 1,600 m to 4,750 m foraging and traveling at night, an area of about 6 ha to 15 ha (Rinehart and Kunz, 2006). (Rinehart and Kunz, 2006)

Communication and Perception

There is little information available on interspecific communication in R. pumilio. Dwarf little fruit bats are microchiropteran bats that use echolocation calls to navigate and find food (Fenton, 1992). Olfaction is probably also an important mode of perception and communication, as many species of fruit bats use olfaction to locate food and communication among mammals is often primarily through olfaction. (Fenton, 1992)

Food Habits

Dwarf little fruit bats have a variable diet that consist of small seeded understory and mid-canopy fruits. They occasionally eat the pollen of flowers, such as the flowers of Vismia duckei, Philodendron billietae, and Cecropis disphylla (Rhinehart and Kunz, 2006). (Rinehart and Kunz, 2006)

  • Plant Foods
  • seeds, grains, and nuts
  • fruit
  • pollen

Predation

Rhinophylla pumilio is subject to predation by squirrel monkeys. Squirrel monkeys have learned how to prey on tent making bats regardless of roost protection. Dwarf little fruit bats roost in small groups under tents made of leaves and stems. They use the vibration of the leaves to alert them of predator presence. Squirrel monkeys will scout the leaves from below, grabbing bats and knocking some to the ground. (Fenton, 1992)

  • Known Predators

Ecosystem Roles

Dwarf little fruit bats are mostly frugivorous and are important seed and pollen dispersers (Fenton, 1992). (Fenton, 1992)

  • Ecosystem Impact
  • disperses seeds
  • pollinates

Economic Importance for Humans: Positive

There is little information available on how Rhinophylla pumilio benefits humans.

Economic Importance for Humans: Negative

There is no evidence that Rhinophylla pumilio negatively effects humans.

Conservation Status

Rhinophylla pumilio is common throughout its geographical range. It is classified as lower risk/least concern by the IUCN red list of threatened species.

Contributors

Tanya Dewey (editor), Animal Diversity Web.

Kristy Craig (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor, instructor), University of Wisconsin-Stevens Point.

Glossary

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

acoustic

uses sound to communicate

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

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

crepuscular

active at dawn and dusk

echolocation

The process by which an animal locates itself with respect to other animals and objects by emitting sound waves and sensing the pattern of the reflected sound waves.

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.

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).

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.

polygynous

having more than one female as a mate at one time

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.

riparian

Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

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

terrestrial

Living on the ground.

tropical

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

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

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

Eisenberg, J., K. Redford. 1999. Mammals of the Neotropics, Vol 3, The Central Neotropics: Ecuador, Peru, Bolivia, Brazil. Chicago: The University of Chicago Press.

Emmons, L. 1990. Neotropical Rainforest Mammals A Field Guide. Chicago: The University of Chicago Press.

Fenton, M. 1992. Bats. NewYork, Ny USA: Facts on File Inc..

Rinehart, J., T. Kunz. 2006. Rhinophylla pumilio. Mammalian Species, No. 791: 1-5.