Black lion tamarin

The black lion tamarin (Leontopithecus chrysopygus), also known as the golden-rumped lion tamarin, is a lion tamarin endemic to the Brazilian state of São Paulo, almost exclusively in Morro do Diabo State Park. A 2020 assessment by the IUCN estimated 1,600 individuals in the wild, 1,200 of them in that park. It lives in groups of 4 to 9 in secondary and primary forest and weighs 300 to 700 grams. Its diet is seasonal: in dryland forest it eats a variety of fruit, while in swampy forest it feeds mainly on the gum of various trees. It spends long periods each day searching for insects and spiders, and about 80 percent of its foraging time goes to insects. Most infant deaths occur within the first two weeks of life.