Cheirogaleusdwarf lemurs

Diversity

Cheirogaleus contains ten species. Only four species have sufficient research done, while the others are understudied. They can only be found in Madagascar and typically avoid humans. An unique characteristic is that they can store fat deposits in their tails and are used for energy during hibernation or topor. They are an arboreal and nocturnal genus. (Blanco, et al., 2021; Hapke, et al., 2005; Petra, 2008)

Geographic Range

Genus Cheirogaleus are endemic to the island of Madagascar and the Ethiopian region. Species of the genus can be found mainly in the northern and southern areas like Cheirogaleus major and Cheirogalues lavasoensis. A few other species can also be found in western and southeastern regions, like Cheirogaleus medius. (Hapke et al. 2005) (Hapke, et al., 2005)

Habitat

Cheirogaleus live in the Madagascar rainforest, the dry deciduous forests, and dry shrubland. They are arboreal and will spend most of their time up in the trees.Based on the particular species and body size of the genus, the area and height of the tree varies. (Lahann 2008) For example, Cheirogaleus major lives in the upper parts of trees while Cheirogaleus medius lives in the middle parts of trees.(Lahann 2008) Typically, smaller species will occupy smaller trees while larger dwarf lemurs will occupy larger trees. (Petra, 2008)

Systematic and Taxonomic History

Cheirogaleus is part of the family Cheirogaleidae along with four other genera. (Pastorini et al. 2001) The closest relative to Cheirogaleus is Allocebus. (Pastrorini, et al., 2001)

  • Synonyms
    • Altililemur (Elliot 1913)
    • Cebuggale (Lesson 1840)
    • Mioxocebus (Lesson 1840)
    • Myspithecus (F. Cuvier 1842)
    • Opolemur (Gray 1873)
  • Synapomorphies
    • Long tails
    • White underbelly
    • Dark rings around eyes
    • Robust eyes
    • Store fat deposits in tail

Physical Description

There are 10 species in the genus that range in color from reddish brown, brown, or grey. They all have a white belly and a long tail. The average body length is 19-27 cm and their average tail length is 16-17 cm long. (Ankel-Simons 2007) Each species has a dark ring around both eyes. They also have big eyes due to being nocturnal. There are no differences between males and females. (Ankel-Simons, 2007)

  • Sexual Dimorphism
  • sexes alike

Reproduction

Cheirogaleus has a monogamous mating system, but in some cases there can also be a polygynadrous system. In the polygynadrous case, it's usually one male with multiple females. Even though there is monogamy, the young are sometimes raised by another male. (Fietz 1999) (Fietz, 1999)

The breeding season starts in October or November and will last until February. The gestation period averages about 70 days. A normal litter typically has one to four infants, (a litter with two is the most common). (Muller 1999) There is a month and a half of parental investment before the infants become independent. It takes about a year before the infants become mature but will take 18 months before females can start reproducing. (Muller, 1999)

Both the female and male contribute to caring for their young. The investment includes include protecting, feeding, and thermoregulation of the offspring until they reach independence from both parents. (Fietz and Dausmann 2003) (Fietz and Dausmann, 2003)

  • Parental Investment
  • male parental care
  • female parental care
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • male
      • female
  • pre-independence
    • protecting
      • male
      • female
  • post-independence association with parents

Lifespan/Longevity

Although there is literature that addresses the lifespan of the Cheirogaleus, the research and educational sources do not provide enough substantive content to reference. ("Cheirogaleus", 2022)

Behavior

Cheirogaleus are solitary at night but typically sleep in groups during the day in the trees. In the wild, they go into hibernation for either 3 or 7 months, but in captivity they go into topor during the winter season or when there is food scarcity. (Blanco et al. 2021) During topor, this genus's body temperature and heart rate will drop. It will occur for 11 days for a few hours at a time. (Blanco et al. 2021) They are are able to live off fat deposits in their tails for energy. (Blanco, et al., 2021)

Communication and Perception

They typically communicate with vocal sounds, but are mostly a quiet genus. One species, sp.Chirogaleus medius, can use ultrasonic vocalization between mothers and infants. (Cherry, Izard, and Simmons 1987) The genus also uses fecal scent markings to establish territory. (Cherry, et al., 1987)

Food Habits

Cheirogaleus are mainly frugivores. While they mostly eat fruit, they can also eat flowers, seeds, nectar, and insects. (Lahann 2007) They are also able to live off of fat deposits in their tail when there is food scarcity and when they go into torpor. (Lahann, 2007)

Predation

Cheirogaleus has few predators. The ones they have are: the ring-tailed mongoose, the Malagasy tree boa, the Madagascar buzzard, and fossas. There's not much known about anti-predator adaptations besides being nocturnal. ("Cheirogaleus", 2022)

Ecosystem Roles

Cheirogaleus help with seed dispersal and pollination of flowers. They are also prey for medium and large carnivores.

  • Ecosystem Impact
  • disperses seeds
  • pollinates

Economic Importance for Humans: Positive

Cheirogaleus live away from the human population, so there's not much economic importance for humans. They can disperse seeds and pollinate flowers, which can provide vegetation for humans. ("Cheirogaleus", 2022)

  • Positive Impacts
  • food
  • pollinates crops

Economic Importance for Humans: Negative

There are no known adverse effects of Cheirogaleus on humans.

Conservation Status

The conversation status ranges from vulnerable to critically endangered on the IUCN list. ("Cheirogaleus" 2022) The vulnerable species include: Cheirogaleus medius, Cheirogaleus major, Cheirogaleus crossleyi. The endangered species include: Cheirogaleus lavasoensis, Cheirogaleus thomasi, Cheirogaleus shethi, and Cheirogaleus andysabini. The critically endangered species is Cheirogaleus sibreei. All of the species are moving down the IUCN list and are all extant. ("Cheirogaleus", 2022)

  • IUCN Red List [Link]
    Not Evaluated

Contributors

Emily Ouellette (author), Colorado State University, Audrey Bowman (editor), Colorado State University.

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.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

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

food

A substance that provides both nutrients and energy to a living thing.

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

granivore

an animal that mainly eats seeds

herbivore

An animal that eats mainly plants or parts of plants.

insectivore

An animal that eats mainly insects or spiders.

island endemic

animals that live only on an island or set of islands.

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).

male parental care

parental care is carried out by males

monogamous

Having one mate at a time.

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.

nectarivore

an animal that mainly eats nectar from flowers

nocturnal

active during the night

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.

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

scrub forest

scrub forests develop in areas that experience dry seasons.

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

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.

ultrasound

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

viviparous

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

References

2022. "Cheirogaleus" (On-line). Accessed May 13, 2022 at https://www.iucnredlist.org/fr/search/map?taxonomies=100091&searchType=species.

Ankel-Simons, . 2007. Primate Anatomy An Introduction. Cambridge, Massachusetts: Academic Press.

Blanco, M., L. Greene, R. Schopler, C. Williams, D. Lynch, J. Browning, K. Welser, M. Simmons, P. Klopfer, E. Ehmke. 2021. On the modulation and maintenance of hibernation in captive dwarf lemurs.. Scientific Reports, 11(1): 5740.

Cherry, J., M. Izard, E. Simons. 1987. Description of ultrasonic vocalizations of the mouse lemur (Microcebus murinus) and the fat-tailed dwarf lemur (Cheirogaleus medius).. American Journal of Primatology, 13(2): 181-185.

Fietz, J. 1999. Monogamy as a rule rather than exception in nocturnal lemurs: the case of the fat-tailed dwarf lemur, Cheirogaleus medius.. Ethology, 105(3): 259-272.

Fietz, O., K. Dausmann. 2003. Costs and potential benefits of parental care in the nocturnal fat-tailed dwarf lemur (Cheirogaleus medius). Folia Primatologica, 74(5,6): 246-258.

Hapke, A., J. Fietz, S. Nash, D. Rakotondravony, B. Rakotosamimanana, J. Ramanamanjato, G. Randria, H. Zischler. 2005. Biogeography of Dwarf Lemurs: Genetic Evidence for Unexpected Patterns in Southeastern Madagascar. International Journal of Primatology, 26: 873-901.

Lahann, P. 2007. Feeding ecology and seed dispersal of sympatric cheirogaleid lemurs (Microcebus murinus, Cheirogaleus medius, Cheirogaleus major) in the littoral rainforest of south-east Madagascar.. Journal of Zoology (London), 271(1): 88-98.

Muller, A. 1999. Aspects of social life in the fat-tailed dwarf lemur (Cheirogaleus medius): inferences from body weights and trapping data.. American Journal of Primatology, 49(3): 265-280.

Pastrorini, J., R. Martin, P. Ehresmann, E. Zimmermann, M. Forstner. 2001. Molecular phylogeny of the lemur family Cheirogaleidae (primates) based on mitochondrial DNA sequences.. Molecular Phylogenetics and Evolution, 19(1): 45-56.

Petra, L. 2008. Habitat Utilization of Three Sympatric Cheirogaleid Lemur Species in a Littoral Rain Forest of Southeastern Madagascar. International Journal of Primatology, 29: 117-134.