This is the smallest marmoset and one of the smallest primates. The size of these primates allows them to feed off slender branches that are out of the reach of their relatives. Pygmy marmosets use their teeth in an unusual way, cutting notches in the bark of trees, which allows them to reach sap. They live in the low plants that grow beneath tall trees in tropical forests. They clamber among the thick vegetation in search of food throughout the day, being most active in the cooler hours at the beginning and end of each day.
Pygmy marmosets have grey-brown fur and tails ringed with red-brown stripes. Their tails are prehensile and can be wrapped around branches. They move cautiously through the tree tops to avoid attack by large birds of prey.
The pygmy marmoset is active in the daytime, but may rest at noon. It is particularly vulnerable to attack by large birds of prey because of its size, so it tries to keep out of sight and to avoid danger. It moves either extremely slowly or in short dashes, punctuated by moments of frozen immobility. Its cryptic coloration also helps it to hide from predators. The pygmy marmoset is primarily a tree-dweller and sleeps in holes in trees. However, it does come down to the ground occasionally in order to feed or to move from one tree to another.
Pygmy marmosets eat fruit, flower buds and insects, but their preferred food is the sweet, sticky sap from certain trees. Their lower canine teeth are specially shaped for gouging holes in tree bark, causing the sap to leak out from the wood beneath. A tree used by a group of pygmy marmosets will be covered in wounds where the animals have repeatedly bitten through the bark.
Like all monkeys, pygmy marmosets live in complex societies. They live in family groups, with two parents and eight or nine offspring. Families sleep together, huddled on branches. Breeding pairs may mate at any time, but most produce small litters - usually twins - in December or June. They are very vocal, uttering a series of whistles, squeaks and clicks. This enables them to communicate any hint of danger in their vicinity. At close quarters, they also communicate by means of facial gestures and body posture.
Distribution: Found in northern South America, restricted to the rainforest areas of southeastern Colombia, eastern parts of Ecuador and Peru, northern Bolivia and western Brazil.
Weight: 120 - 140 g (4 - 5 oz); females are smaller.
Length: 29 - 36 cm (11.4 - 14.1 in) overall; the tail is longer than the body.
Maturity: 1.1 - 1.6 years.
Gestation Period: 120 - 135 days.
Breeding: 2, occasionally 3; males are responsible for carrying the young for 2 months until they are largely weaned.
Diet: Sap from trees, returning daily to feed on the exudate; also eats fruit and invertebrates.
Lifespan: Up to 11 years.
The face is quite broad, with the eyes appearing close together and the ears hidden by fur.
Legs and feet
Nimble by nature, these marmosets can run up and down branches easily.
Tawny patterning helps to conceal the presence of these marmosets.
Their agility helps pygmy marmosets to catch invertebrates. They can jump vertically up to 5 m (16 ft), and bound between branches.
Long and slender, this is banded along its length and tapers to a tip. It is not prehensile.
Larger snakes hunt pygmy marmosets, as do wild cats. They are also vulnerable to birds of prey flying over the canopy.
Facial gestures are used to communicate.