Predators of pygmy three-toed sloths have not been reported. However, like other sloths, they are very slow-moving animals with long, hair that often grows algae, allowing them to blend in well in their leafy habitats. Other sloth species are preyed on by harpy eagles (Harpia harpyja), jaguars (Panthera onca), jaguarundis (Puma yagouaroundi) and ocelots (Leopardus pardalis).
Anti-predator Adaptations: cryptic
Bradypus pygmaeus is similar to Bradypus variegatus but smaller. Pygmy three-toed sloths have buff-colored faces with dark circles that surround the eye and go outwards to their temples. Clay-orange fur covers the face, starting underneath the dark eye circles. The hair on the head and shoulders is long and bushy, distinctive against the shorter facial hair and making it look as if these sloths have a hood. The throat is brown-gray and the dorsum is speckled and has a dark mid-sagittal stripe. Males differ in that they have a dorsal ginger speculum with fuzzy hair following the margin. Pygmy three-toed sloths have in total 18 teeth, 10 from the upper jaw which consists of 2 anterior chisel-shaped teeth and 8 molariform teeth. On the bottom jaw there are 8 teeth; 2 anterior chisel-shaped, and 6 molariform teeth. The skull is small in comparison to other closely related species, lacks foramina in the anterodorsal nasopharynx, and doesn't have pterygoid sinuses that are inflated. The zygomatic arch is incomplete with slim roots, and the process of the jugal descends long and thin. Bradypus pygmaeus also have large external auditory meatus. Like other sloths, body temperature regulation is likely to be imperfect, making them heterothermic.
Range mass: 2.5 to 3.5 kg.
Average mass: 2.9 kg.
Range length: 485 to 530 mm.
Average length: 505.4 mm.
Other Physical Features: endothermic ; heterothermic ; bilateral symmetry
Sexual Dimorphism: sexes colored or patterned differently
Little information is known at this time about the lifespan or longevity for Bradypus pygmaeus. Other species of sloths have been known to live 30 to 40 years in captivity.
Pygmy three-toed sloths have been found living only in coastal, red mangroves at sea level.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: rainforest
Aquatic Biomes: coastal
Bradypus pygmaeus was recently discovered in 2001, which is why a lot of information is lacking for the species. Compared to Bradypus variegatus Pygmy three-toed sloths are 15% smaller in total length, and 40% smaller in their mass.
There is little information on communication in Bradypus pygmaeus. Like other sloths, pygmy three-toed sloths are likely to have relatively poor eyesight. They may use vocalizations and are likely to use chemical cues in communication.
Perception Channels: visual ; tactile ; acoustic ; chemical
Because of their extremely restricted range, habitat degradation in that area, increasing tourism, and illegal hunting, Bradypus pygmaeus has been listed as Critically Endangered by the IUCN.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: critically endangered
There are no known adverse effects of Bradypus pygmaeus on humans.
There are no known benefits to humans from Bradypus pygmaeus at this time.
Because pygmy three-toed sloths are a recently described species, little is known about their ecosystem roles. They are hosts to various parasites, may influence vegetation through their browsing, and act as prey for larger, arboreal predators.
Pygmy three-toed sloths are arboreal folivores. They eat leaves from many different kinds of trees and have low metabolic rates.
Plant Foods: leaves
Primary Diet: herbivore (Folivore )
Bradypus pygmaeus, commonly called monk, dwarf, or pygmy three-toed sloth, is found only on the Isla Escudo de Veraguas of Bocas del Toro, which is located off the coast of Panama. This island is small, only about 5 square kilometers in area.
Biogeographic Regions: neotropical (Native )
Other Geographic Terms: island endemic
There is little information on the Bradypus pygmaeus mating system. However, in other Bradypus species, there is evidence that males compete for access to mating opportunities with receptive females.
Reproduction in Bradypus pygmaeus has not been researched enough to report details. Bradypus torquatus has been studied more extensively. They copulate towards the end of the dry season and early wet season, which occurs from August through October, which results in gestation and lactation occurring during times of plenty of food. Births occur from February to April, marking the end to the wet season and start of the dry season. One infant is born after a gestation period of 6 months. The interbirth interval is 1 year for maned sloths.
Breeding interval: A close relative, Bradypus torquatus, breeds once yearly, but the breeding interval for B. pygmaeus is not known.
Average number of offspring: 1.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous
Female pygmy three-toed sloths invest heavily in young through gestation and lactation, as do females in other sloth species. Details of parental care are not reported for pygmy three-toed sloths, but related species care for their young for up to 6 months.
Parental Investment: precocial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female)
The pygmy three-toed sloth (Bradypus pygmaeus), also known as the monk sloth or dwarf sloth, is a species of sloth in the family Bradypodidae. The species is endemic to Isla Escudo de Veraguas, a small island off the Caribbean coast of Panama. The species was first described by Robert P. Anderson of the University of Kansas and Charles O. Handley Jr., of the Smithsonian Institution in 2001. The pygmy three-toed sloth is significantly smaller than the other three members of its genus, but otherwise resembles the brown-throated three-toed sloth. According to Anderson and Handley Jr., the head-and-body length is between 48 and 53 centimetres (19 and 21 in), and the body mass ranges from 2.5 to 3.5 kg (5.5 to 7.7 lb).
This sloth, like other sloths, is arboreal (tree-living) and feeds on leaves. It has a body adapted to hang by its limbs; the large curved claws help the sloth to keep a strong grip on tree branches. It lives high in the canopy but descends once a week to defecate on the forest floor.[3] It is symbiotically associated with green algae, that can provide it with a camouflage. Details of mating behavior and reproduction have not been documented. The pygmy three-toed sloth is found exclusively in the red mangroves of Isla Escudos de Veraguas, restricted to an area of 4.3 square kilometres (1.7 sq mi). A 2012 census of pygmy three-toed sloths estimated the total population at 79. The IUCN lists the pygmy three-toed sloth as critically endangered and they are listed on the world's 100 most threatened species.
The pygmy three-toed sloth was first described by Robert P. Anderson of the University of Kansas and Charles O. Handley Jr., of the Smithsonian Institution in 2001. The researchers noted that the three-toed sloths found on Isla Escudo de Veraguas were significantly smaller than those that occur on the nearby outer islands of Bocas del Toro Province. Moreover, they differ from other populations in terms of pelage and cranial characteristics. Hence, they considered the three-toed sloths in Isla Escudo de Veraguas to be an independent species and formally described it from the skin and skull of an adult female. The researchers further pointed out that Isla Escudos de Veraguas is the oldest island and located farthest from the mainland, which began breaking up into small islands due to rises in sea levels 10,000 years ago. They proposed that this species evolved from an isolated population that had originated from the mainland population of brown-throated three-toed sloths; it gradually differentiated enough to become an independent species through insular dwarfism.[4] In another study the following year, the researchers observed that the mean body size of three-toed sloths on an island decreases linearly as the age of the island increases; the area of the island and the distance from the mainland, however, do not appear to significantly affect dwarfing.[5]
The pygmy three-toed sloth is one of the four extant members of the genus Bradypus, and is classified under the family Bradypodidae.[6] According to molecular phylogenetic analysis, Bradypodidae nests with Megalonychidae, Megatheriidae and Nothrotheriidae in the sloth superfamily Megatherioidea.[7][8] The generic name Bradypus is the combination of two Greek words: brady ("slow") and pous ("foot").[9] The specific name pygmaeus comes from the Greek pugmaios ("as small as a fist").[10] 'Monk sloth' and 'dwarf sloth' are two other names for this sloth.[11]
The pygmy three-toed sloth is significantly smaller than the other members of its genus, but otherwise resembles the brown-throated sloth. According to Anderson and Handley Jr., the head-and-body length is between 48 and 53 centimetres (19 and 21 in), and the body mass ranges from 2.5 to 3.5 kg (5.5 to 7.7 lb). The brown-throated sloth is nearly 40% heavier and 15% smaller in head-and-body length than the pygmy three-toed sloth. Moreover, the brown-throated sloth is lighter on the crown. The face is buff to tan; a dark band runs across the brow, surrounded by an orange patch. The throat is gray to brown, lighter than the underbelly; the dark brown back is spotted and has a dark stripe along the midline. Facial hair is short, while the long, rough hair on the crown and shoulders forms a hood. The grayish limbs have three claws each. The tail is 4.5 to 6 centimetres (1.8 to 2.4 in) long.[4][5][12]
They have a relatively small and slender skull, with a large external auditory meatus, narrow squamosal and mandibular processes, a minuscule stylomastoid foramen, and usually lack foramina for the external carotid artery and anterodorsal (meaning in front and toward the back) nasopharynx. The dental formula of three-toed sloths is: 54–5[13] Two of the teeth in each jaw are incisor-like, although those in the upper jaw are small or may be absent. Many of the features found in pygmy sloths are thought to be indicative of a relatively rapid evolution of a new species in an isolated, island habitat.[4]
They host algae inside their fur which causes them to have a greenish color. The algae is generally more noticeable on the top of their head and neck, dorsal portions of the forelimbs, and upper backside.[14]
The pygmy three-toed sloth is unique in that it is found exclusively in the red mangroves of Isla Escudo de Veraguas; the island has a small area of approximately 4.3 square kilometres (1.7 sq mi). A 2012 census of pygmy three-toed sloths estimated the total population at 79 – of which 70 occurred on mangroves and 9 in the surroundings. The population density was calculated as 5.8 per hectare (2.3 per acre). The total area occupied by mangroves on the island was estimated to be around 10.67 hectares (0.0412 sq mi).[15] While their population has presumably always been low due to their restricted range, the 2012 census found far lower numbers than had been estimated (less than 500) by the IUCN in 2010.[16]
The IUCN lists the pygmy three-toed sloth as critically endangered; it is also listed in CITES Appendix II. According to the IUCN, conservation efforts are being hampered by conflict between local peoples and the government.[1] Threats to the sloth's survival include timber harvesting and human settlement, that might lead to habitat degradation.[17] After several observations, the corpses of the pygmy three-toed sloth were found to be unharmed physically, suggesting that predation is not a major threat. Instead, disease, habitat loss, or natural causes were larger factors in the species’ death. A study in 2011 showed that there were 79 pygmy sloths in the wild. Studies in 2010 and 2013 suggested a recent population bottleneck and decline in genetic variability.[1]
The pygmy three-toed sloth, like others in its genus, is an arboreal (tree-living) animal. This sloth can spend as many as 15 to 20 hours per day on trees. It moves at an extremely slow speed of 0.24 kilometres per hour (0.15 mph), making it one of the slowest animals.[18] The pygmy three-toed sloth is symbiotically related to green algae; a 2010 study investigated this in detail. Different sloths harbour different types of algae – only Tricophilus species were found on the brown-throated and pygmy three-toed sloths. These algae discolor the fur of the sloth, giving it a greenish hue – this serves as an efficient camouflage.[19] Some of these algae might be transferred to offspring through the mother, others may be picked up from the surroundings over time.[20] The smaller size of pygmy sloths reduces their energy requirements for survival and reproduction, making them an apparent example of insular dwarfism.[5] A BBC documentary, in which English naturalist Chris Packham recognizes the pygmy three-toed sloth as the first in his list of the top ten discoveries in the 2000s, shows a rare clip of a swimming pygmy three-toed sloth.[21]
Like other sloths, the pygmy three-toed sloth feeds on leaves. It feeds on red mangrove leaves, which are relatively poor in nutrients and coarser than the tender leaves of Cecropia species eaten by brown-throated sloths on the mainland.[5] Details of mating behavior and reproduction have not been documented.[11]
The pygmy three-toed sloth (Bradypus pygmaeus), also known as the monk sloth or dwarf sloth, is a species of sloth in the family Bradypodidae. The species is endemic to Isla Escudo de Veraguas, a small island off the Caribbean coast of Panama. The species was first described by Robert P. Anderson of the University of Kansas and Charles O. Handley Jr., of the Smithsonian Institution in 2001. The pygmy three-toed sloth is significantly smaller than the other three members of its genus, but otherwise resembles the brown-throated three-toed sloth. According to Anderson and Handley Jr., the head-and-body length is between 48 and 53 centimetres (19 and 21 in), and the body mass ranges from 2.5 to 3.5 kg (5.5 to 7.7 lb).
This sloth, like other sloths, is arboreal (tree-living) and feeds on leaves. It has a body adapted to hang by its limbs; the large curved claws help the sloth to keep a strong grip on tree branches. It lives high in the canopy but descends once a week to defecate on the forest floor. It is symbiotically associated with green algae, that can provide it with a camouflage. Details of mating behavior and reproduction have not been documented. The pygmy three-toed sloth is found exclusively in the red mangroves of Isla Escudos de Veraguas, restricted to an area of 4.3 square kilometres (1.7 sq mi). A 2012 census of pygmy three-toed sloths estimated the total population at 79. The IUCN lists the pygmy three-toed sloth as critically endangered and they are listed on the world's 100 most threatened species.
