Hipposideridaeleaf-nosed bats, roundleaf bats, and trident bats

Diversity

Hipposideridae, Old World leaf-nosed bats, is one of eighteen families that make up the order Chiroptera, and consists of nine genera. The largest genus is Hipposideros (roundleaf bats), which consists of 76 species. The remaining genera are Asellia (trident leaf-nosed bats), Anthops (flower-faced bats), Aselliscus (trident bats), Cloeotis (Percival's trident bat), Coelops (tailless leaf-nosed bats), Paracoelops (orange leaf-nosed bat), Rhinonicteris (orange leaf-nosed bat), and Triaenops (trident bats). Hipposiderids live in tropical and subtropical regions of Africa, south Asia, Australia, the Philippine Islands, and the Solomon Islands. They can be found in deserts, dunes, savannas, grasslands, forests, rainforests, scrub forests and mangroves. Most species roost in dark, enclosed spaces, but some do roost in open areas. Hipposiderids range from 28 to 110 mm in body length, 30 to 110 mm in forearm (wing) length, and may or may not have a tail, up to 60 mm in length. Colors range from white to red to dark brown depending on species, geographic area, sex, and age, and pelage also varies in length and texture. They may have small or large ears, and some species’ ears are interconnected along the dorsal surface of the head. The appearance of the noseleaf is highly variable among genera. Hipposiderids show a great deal of diversity in roosting behavior and reproductive habits and show slight differences in feeding habits from genus to genus. (Kunz and Racey, 1998; Nowak, 1994; Hill and Smith, 1992; Kunz and Racey, 1998; Nowak, 1994; Wilson and Reeder, 2005)

Geographic Range

Members of Hipposideridae are found throughout tropical and subtropical regions of the Old World. These Old World leaf-nosed bats are found in Africa, southern Asia, the Philippine Islands, the Solomon Islands, and Australia. (Nowak, 1994; Simmons and Conway, 1997)

Habitat

Hipposideridae inhabits tropical and subtropical habitats and roosting preferences vary by genera. Hipposiderids have been found roosting in caves, mines, hollow trees, buildings, and man-made underground compartments like cellars and tombs. In Africa, Fulvus round-leaf bats are often found in the burrows of Hystrix (Old World porcupines) and members of the genus Asellia roost in the inner walls of wells, in caves, and in man-made structures. Though Percival's trident bats live in forests and generally roost in trees, in Taiwan they have been discovered in abandoned Japanese bomb shelters, also known as pillboxes. (Nowak, 1994)

Physical Description

A defining characteristic of Hipposiderids is their elaborate noseleaf. The noseleaf consists of fleshy protrusions on top of a U-shaped rhinarium (i.e., the wet surface surrounding the nostrils). Hipposiderids have an erect transverse leaf within the noseleaf as well as smaller accessory leaflets. The common name of many genera corresponds to the shape of the noseleaf. For example, flower-faced bats have two circular lateral leaflets, the smaller of which is superimposed onto the larger, resulting in a noseleaf resembling the petals of a flower. Differences in noseleaf characteristics are commonly used to discern between genera. These 'appendages' are thought to be related to nasal echolocation, and may help to focus and modify echolocation signals. (Dewey, 2011; Nowak, 1994)

Pelage of hipposiderids varies greatly both between and within taxa. Pelage can be white, light beige, pale yellow, dark yellow, orange, red, red-brown, light brown, dark brown, gray, or dark gray. Some species have white patches of fur, while others have 2 different color phases. Often, venter pelage is lighter than dorsum pelage. Pelage also differs interspecifically by length and texture or silkiness. Hipposiderid skulls have a number of unique features that differentiate them from other bat families. For example, they have no post-orbital processes, the nasal portion of the premaxilla is absent, and the premaxilla is not fused to the maxilla. They have dilambdodont molars , and their dental formula is I1/2 C1/1 P1–2/2–3 M3/3, giving them a total of 28 to 30 teeth. Hipposiderids do not have a tragus, the fleshy protuberance present at the opening of the ear in many bats. A membrane spanning the dorsal surface of the head connects their ears, which exhibit a great deal of variation in size. (Dewey, 2011; Jones, 2001; Nowak, 1994; Simmons and Conway, 1997)

Hipposideridae shares many traits with the family Rhinolophidae, and some accounts consider Hipposideridae a sub-family of Rhinolophidae. Both hipposiderids and rhinolophids lack post-orbital processes and the nasal portion of the premaxilla, as well as having a premaxilla that is not fused to the maxilla, dilambdodont molars, and a U- or horseshoe-shaped rhinarium. However, hipposiderids can be differentiated from rhinolophids using a number of different characteristics. Hipposiderids generally have a more rounded noseleaf, while the noseleaf of rhinolophids is spear-like and pointed. Hipposiderids have only two bones in each toe, while rhinolophids have three in all except the first toe, which has two. Rhinolophids always have three lower premolars on each side of the mandible and hipposiderids have only two. The two families also differ in the structure of their shoulder and hip girdles. Finally, rhinolophids have a sella, a flattened leaflet in the middle of the noseleaf structure, that is not present in hipposiderids. ("Leaf-nosed bat", 2009; Nowak, 1994; Simmons and Conway, 1997)

  • Sexual Dimorphism
  • sexes alike

Reproduction

Not enough information is known about hipposiderid mating systems to make accurate generalizations about the family as a whole; however, research on individual species provides limited but important insight. Only one example of a polygynous mating in hipposiderids is known. Colonies of Commerson's roundleaf bat, which can contain up to 500,000 individuals, are divided into small harems consisting of one adult male and several adult females, with whom the male mates. Mating occurs seasonally, during the fall, and females give birth to a single young during spring after storing sperm over winter. (Dewey, 2011; Nowak, 1994)

Breeding season and birthing season vary among hipposiderid species. For example, bi-colored leaf-nosed bats and ashy roundleaf bats mate in October and give birth in April. Although birthing season varies slightly, coinciding with peak rainy season when food is most abundant, Sundevall's leafnosed bats give birth in April north of the equator and in October south of the equator. Fulvus roundleaf bats mate in November and give birth in late April. Although the specific times vary among species, birthing among hipposiderids generally occurs during spring. Female hipposiderids give birth to a single young per pregnancy. Gestation lasts from 90 days in cyclops roundleaf bats to 220 days in Sundevall's leafnosed bats in South Africa. Females typically carry their young for a few weeks after giving birth. For example, Fulvus roundleaf bats produce a single young, which the female carries for 20 to 22 days. Age at weaning, age at first flight, and age at independence appears to vary according to latitude. Species subject to greater seasonality appear to mature more quickly than those resident to more tropical regions. In at least one species, Sundevall's leafnosed bats of Nigeria, delayed implantation occurs. The egg does not implant in the uterine lining for up to 2 months after fertilization, and as a result, young are born when prey are more abundant, directly before the rainy season. (Nowak, 1994; Slaughter and Walton, 1970; Nowak, 1994; Slaughter and Walton, 1970; Dewey, 2011; Nowak, 1994; Slaughter and Walton, 1970)

Females are the primary care givers in hipposiderids. Female typically carry their young for a few weeks after birth and prior to weaning. Females have "pubic teats", which their young hold on to during the carrying period. Little is known of lactation and weaning in hipposiderids. However, lactation lasts for about 40 days in the genus Asellia, and Taiwanese leaf-nosed bats are usually weaned at 7 weeks old. Tropical species are thought to be weaned by 8 to 20 weeks and time to independence appears to vary according to latitude, as tropical species reach sexual maturity between 16 and 24 months, and temperate species reaching sexual maturity by 6 to 8 months. (Dewey, 2011; Slaughter and Walton, 1970)

  • Parental Investment
  • precocial
  • female parental care
  • pre-hatching/birth
    • provisioning
      • female
  • pre-weaning/fledging
    • protecting
      • female
  • pre-independence
    • provisioning
      • female

Lifespan/Longevity

Information regarding the lifespan of hipposiderids is limited, as a majority of species in this family are not well-known. However, some species have been found to live more than 10 years. ("Leaf-nosed bat", 2009)

Behavior

Hipposiderids, like all bats, are motile and capable of flight. They are nocturnal and roost in caves, mines, hollow trees, buildings, cellars, and abandoned bomb shelters. Roosting practices of hipposiderids vary widely between genera and species. While some roost as individuals, others, such as certain species of Hipposideros, roost in small groups. Some species roost in colonies of hundreds or even thousands of individuals. Pilbara leaf-nosed bats have been found in groups of more than 5,000 individuals, and Sundevall’s roundleaf bats were once discovered in a group of more than 500,000 in a cave in Gabon, Africa. It has been suggested that large colonies of Sundevall’s roundleaf bats separate into harem groups consisting of seven adult females and one adult male. Alternatively, cyclops roundleaf bats congregate in groups of twelve or fewer females, and no males are usually present. One species is thought to migrate. ("Leaf-nosed bat", 2009; Nowak, 1994)

While roosting, hipposiderids do not touch each other, including those species that roost in large groups. A group of 5,000 Pilbara leaf-nosed bats were observed to each be spaced at least 15 cm from each other. Other genera are reported to maintain an interindividual roosting distance of 30 to 40 cm. Hipposiderids are generally found evenly spaced while roosing. Some species roost with bats of other genera or even other families. For example, trident leaf-nosed bats have been found roosting with trident bats as well as Kuhl's pipistrelle, and Pilbara leaf-nosed bats often roosts with Australian false vampire bat and ghost bats. In addition, some members of the genera Hipposideros, Asellia, and Coelops hibernate. Trident leaf-nosed bats in the deserts of Iraq were found hibernating in cellars and tombs between mid-September and mid-November. When roosting, hipposiderids fold their wings around themselves. ("Leaf-nosed bat", 2009; Jones, 2001; Nowak, 1994)

Communication and Perception

Like most Microchiroptera, members of the family Hipposideridae have relatively small eyes, indicating that vision may not be as important as echolocation for navigation and foraging purposes. However, vision may be used to detect objects past the range of echolocation. Hipposiderids, like all Microchiroptera, do not have color vision. (Nowak, 1994)

Unlike most microchiropterans that emit echolocation via the mouth, hipposiderids produce echolocation sounds with the larynx and emit the sound through their nostrils. The sounds produced are considered ultrasonic because they have higher frequencies than the normal range of human hearing. Hipposiderid echolocation calls contain a long constant-frequency (CF) component (i.e., one frequency is maintained throughout the duration of the call) and a much shorter frequency-modulated (FM) component. The CF segment of the call is used to determine the general structure of the local environment and to give a coarse location of potential prey and is preceded or followed by a brief FM segment, which aids in homing in on the location of a target. In general, the calls of larger bats have a tendency to be longer and lower in frequency, whereas the calls of smaller bats have a tendency to be shorter and higher in frequency. Evidence suggests that the calls of hipposiderids are typically higher in frequency relative to body mass than other bat families. Little information is available regarding the use of sound and echolocation for intraspecific communication, though audible sounds may be used to communicate during courtship or between mother and pup. (Nowak, 1994; Thomas, et al., 2004)

Many hipposiderid species have a small sac just posterior to the nose leaf. The sac, which is possessed primarily by males, secretes a waxy substance that may be used during mating season to attract mates or fend of potential rivals. (Dewey, 2011)

Food Habits

Although little information is available on the diets of most hipposiderid species, they are considered to be primarily insectivorous. Those species that have been studied prefer cicadas, cockroaches, termites, and beetles. The beetle larvae prey of Commerson's roundleaf bats live in wild figs, which results in the addition of small amounts of fruit to their otherwise insectivorous diet. (Graham and Reid, 1994; Nowak, 1991; Walton and Richardson, 1989)

Hipposiderids have excellent echolocation, and catch most of their prey via aerial hawking and gleaning. They usually fly only a few meters above the ground while echolocating for potential prey. Although most species are thought to prey on flying insects, some occasionally feed on flightless insects such as ants. Hipposiderids are generally territorial and hunt and feed within a specific range. For example, members of the genus Asellia, have been observed flying more than a mile through the desert to their feeding territory. Often, hipposiderids bring captured prey back to their roost prior to consumption. When chewing, the jaws of hipposiderids move side-to-side and up and down, simultaneously. This shearing motion helps break down the chitinous exoskeleton of insect prey. (Graham and Reid, 1994; Nowak, 1991; Walton and Richardson, 1989)

Predation

Hipposiderids are preyed upon by a number of small nocturnal mammals with the ability to capture them mid-flight or locate their roosts. In many localities, the major predator of hipposiderids is snakes, which are sometimes able to locate their roosting sites. During flight, hipposiderids can be captured and eaten by various birds of prey including hawks, falcons, and owls. Furthermore, in Australia, members of the family Dasyuridae have been known to locate hipposiderid roosts. In conjunction with their ability to fly, the nocturnal lifestyle of bats helps reduce predation as does the colonial roosting behavior of many species. (Walton and Richardson, 1989)

Ecosystem Roles

As insectivores, hipposiderids help control insect pest populations. While little information exists on potential endoparasites of hipposiderids, like most bats, they are probably host to a number of ectoparasitic arthropods including lice, mites and fleas. (Graham and Reid, 1994; Hill and Smith, 1992; Kunz and Racey, 1998; Nowak, 1991; Nowak, 1994)

Commensal/Parasitic Species

Economic Importance for Humans: Positive

As insectivores, hipposiderids help control insect pest populations that might otherwise spread disease or damage crops. The guano of hipposiderids is locally used as a nitrogen rich fertilizer. (Nowak, 1991; Walton and Richardson, 1989)

  • Positive Impacts
  • produces fertilizer
  • controls pest population

Economic Importance for Humans: Negative

Hipposiderids cause little economic damage. There are no known pathogens specific to Hipposideridae that are harmful to people or domesticated animals. However, bats occasionally roost in occupied buildings, which can be destructive and has the potential to spread disease. Any species of bat infected with rabies could potentially bite and transmit the pathogen to humans. (Nowak, 1991; Walton and Richardson, 1989; Nowak, 1991; Walton and Richardson, 1989)

Conservation Status

As a family, hipposiderids are not a particularly threatened group. However, many species are not well understood and as a result, potential conservation needs are unknown. The International Union for Conservation of Nature (IUCN) lists 5 species as either endangered or critically endangered, and another 10 species are listed as vulnerable. Of the 84 species listed, 7 are classified as near threatened, 44 are listed as least concern, and the remaining 18 are classified as data deficient. Habitat loss and deforestation are serious concerns and their greatest threats. In specific cases, habitat loss has been so extreme that several species are now classified as endangered and some local populations are nearing extirpation. For example, Thailand leaf-nosed bats have been subjected to severe range contraction due to deforestation, which has resulted in a population reduction of 20% in just the last 5 years. Durga Das's leaf-nosed bats have had nearly all of their native range destroyed and now only roost in the homes of three different villages in central India. Due to deforestation, Orbiculus leaf-nosed bats are now resident to only two locations in Indonesia and Malaysia. Lamotte's roundleaf bats can be found in a single cave on the island of Guinea, and are classified as critically endangered. If conservation efforts are to be successful, habitat loss must be slowed and reforestation projects should be encouraged in critical habitat areas. (Dewey, 2011; IUCN, 2008; Nowak, 1991; Walton and Richardson, 1989)

  • IUCN Red List [Link]
    Not Evaluated

Contributors

Lauren Hall (author), University of Michigan-Ann Arbor, Laura Jadwin (author), University of Michigan-Ann Arbor, Ian Winkelstern (author), University of Michigan-Ann Arbor, Phil Myers (editor), University of Michigan-Ann Arbor, John Berini (editor), Animal Diversity Web Staff.

Glossary

Australian

Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.

World Map

Ethiopian

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

World Map

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

acoustic

uses sound to communicate

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.

carnivore

an animal that mainly eats meat

causes disease in humans

an animal which directly causes disease in humans. For example, diseases caused by infection of filarial nematodes (elephantiasis and river blindness).

causes or carries domestic animal disease

either directly causes, or indirectly transmits, a disease to a domestic animal

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.

delayed fertilization

a substantial delay (longer than the minimum time required for sperm to travel to the egg) takes place between copulation and fertilization, used to describe female sperm storage.

delayed implantation

in mammals, a condition in which a fertilized egg reaches the uterus but delays its implantation in the uterine lining, sometimes for several months.

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

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.

female parental care

parental care is carried out by females

forest

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

heterothermic

having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

hibernation

the state that some animals enter during winter in which normal physiological processes are significantly reduced, thus lowering the animal's energy requirements. The act or condition of passing winter in a torpid or resting state, typically involving the abandonment of homoiothermy in mammals.

insectivore

An animal that eats mainly insects or spiders.

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.

nocturnal

active during the night

oriental

found in the oriental region of the world. In other words, India and southeast Asia.

World Map

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.

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

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.

solitary

lives alone

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.

ultrasound

uses sound above the range of human hearing for either navigation or communication or both

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.

young precocial

young are relatively well-developed when born

References

2009. "Leaf-nosed bat" (On-line). Encyclopaedia Britannica Online. Accessed February 27, 2009 at http://www.britannica.com/EBchecked/topic/693386/leaf-nosed-bat.

Adams, R., S. Pedersen. 2000. Ontogeny, Functional Ecology, and Evolution of Bats. Cambridge, UK: Cambridge University Press.

Dewey, T. 2011. "Hipposiderinae (Old World leaf-nosed bats)" (On-line). Grzimek's Animal Life. Accessed April 25, 2011 at http://animals.galegroup.com.

Graham, G., F. Reid. 1994. Bats of the World. New York: St Martin's Press.

Hill, J., J. Smith. 1992. Bats: A Natural History. Austin, TX: University of Texas Press.

IUCN, 2008. "IUCN 2008 Red List" (On-line). Accessed February 15, 2009 at http://www.iucnredlist.org/search.

Jones, G. 2001. Bats. Pp. 754-785 in D MacDonald, ed. The Encyclopedia of Mammals. Oxfordshire, UK: Andromeda Oxford Limited.

Kunz, T., P. Racey. 1998. Bat Biology and Conservation. Washington and London: Smithsonian Institution Press.

Nowak, R. 1994. Walker's Bats of the World. Baltimore: Johns Hopkins University Press.

Nowak, R. 1991. Walker's Mammals of the World: Fifth Edition. Baltimore and London: The Johns Hopkins University Press.

Simmons, N., T. Conway. 1997. "Tree of Life Web Project" (On-line). Rhinolophidae. Horseshoe Bats.. Accessed February 26, 2009 at http://tolweb.org/Rhinolophidae/16126/1997.01.01.

Slaughter, B., D. Walton. 1970. About Bats: A Chiropteran Biology Symposium. Dallas: Southern Methodist University Press.

Thomas, J., C. Moss, M. Vater. 2004. Echolocation in Bats and Dolphins. Chicago: University of Chicago Press.

Walton, D., B. Richardson. 1989. Fauna of Australia Volume 1B: Mammalia. Canberra, Australia: Australian Government Publishing Service.

Wilson, D., D. Reeder. 2005. Mammal Species of the World. A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press.