The Titis, or Titi monkeys, are the New World monkeys belonging to the genus Callicebus. They are the only living members of the Callicebinae subfamily, which also contains the extinct genera Xenothrix, Paralouatta, Carlocebus, Antillothrix, Lagonimico, and possibly also Tremacebus.

These monkeys reside on South America, from Colombia to Brazil, Peru and north Paraguay.

Depending on the species, titis have a head and a body length of 9.1 to 18 inches and a tail, which is longer than the head and the body, of 10 to 22 inches. The different titi species vary considerably in coloring, but look a lot like each other in the majority of other physical ways. They have long and soft fur, and it is normally reddish, brownish, grayish, or blackish, and is most species the underside is a lighter color or more rufescent than the upper side. Some species have contrasting black or whitish forehead, while all members of the subgenus Torquatus have a white half-collar. The tail is always furry and isn’t prehensile.

As they are diurnal and arboreal, titis show a preference for dense forest near water. They easily jump from branch to branch, earning them their German name, Springaffen. They sleep during the night, but also take a midday nap.

The titis are territorial. They reside in family groups that consist of parents and their offspring, roughly 2 to 7 animals in total. They defend their territory by shouting chasing off intruders, but rarely engage in actually fighting. Their grooming and communication is significant for the co-operation of the group. They can usually be seen in pairs sitting or sleeping with their tails entwined.

The diet of the titis is made up mostly of fruits, although they also eat leaves, insects, flowers, bird eggs, and small vertebrates.

These monkeys are monogamous, mating for life. The females give birth to a single offspring after about a five month gestation period. Twins occur very rarely, having been documented in only 1.4 percent of all births in captive groups of C. moloch. While the second infant normally doesn’t survive, cases where neighboring groups have adopted infants are known, proposing that twins might be reared successfully under certain circumstances. Frequently, it is the father who cares for the offspring, carrying it and bringing it to the mother only for nursing. The young are weaned after 5 months and are fully grown after 2 years old. After 3 or more years, they leave their family group in order to find a mate. While the life expectancy of most species isn’t clear, the members of the subgenus Torquatus might live for up to 12 years within the wild, while members of the C. moloch group have been known to live for more than 25 years within captivity.

The number of known species of these monkeys has doubled in recent years, with four, C. stephennashi, C. Bernhard, C. caquetensis, and C. aureipalatii, being described from the Amazon basin since 2000.

Image Caption: Dusky Titi Monkey (Callicebus brunneus). Credit: Cliff/Wikipedia (CC BY 2.0)