This is a baby red backed squirrel monkey. This species of monkey is highly endangered. Squirrel monkeys are aptly named since they are the size of a squirrel and weigh up to 1 kg - Costa Rican Jungle stock photo. Costa Rica has four species of monkeys, including the capuchin, mono titi (red backed squirrel monkey), howler and spider. Photographed by professional wildlife photographer Christina Craft.