Features

Brachyteles arachnoides (Southern Muriqui or Wolly spider monkey) belongs to the family, subfamily Atelinae monotypic genus, which belong to the genera Ateles sp. (Spider-monkey) and Lagothrix sp. (Woolly-monkey).

The  woolly spider monkey is the largest primate in the Americas. This classification is based on terms of body size and also according to the relationship between relative brain size relative to the size corporal. The males get to weigh 15 kg and to measure 595 mm (total length of the head and body) and the females, 13 Kg and to measure 573 mm.

They possess the coat thickens and soft, of brown-yellowish color. His face is black and without hair, sometimes presenting despigmentation, with outlines of ring of clearer hair. The skin of the hands, feet and plant of the tail are black.

A characteristic of the gender is that as much the youths as the adults of both sexes they project the abdomen, forming a belly, due, probably, to the great volume of ingested leaves. The arms are long and usually in hook form, with thumb vestigial or inexistent – an important characteristic to differentiate the two species. The tail is prehensile and long, exceeding the length of the body, with nude final third, serving as tactile surface. The dental formula of the species belonging to this gender is i2/2, c1/1, pm 3/3, m3/3 = 36. The males possess a led scrotum and the females a prominent clitoris, what facilitates the identification of the sexes.

Its main mode of locomotion is by brachiation, held hands and through the elongated members. The thumb is vestigial or absent, and the hand is used as hook in handling performance.