The first mention of the ashy-grey titi monkey seems to come from Edwards Griffith’s account of the Ash Coloured Monkey (Simia cineracia) 1821), with a plate of an animal resembling a titi monkey. The plate is after an animal that was brought to his country, but that he has never seen alive. He guessed that is belongs to the titi monkeys, but he is not sure. He never mentioned it again in his works on zoology.
The official description of Callicebus cinerascus was published in 1823 by John Baptist von Spix in his famous “Simiarum et Vespertilionum Brasiliensium species novae”. He collected the animal in Brazil; according to him in the forests around the Putumayo, but later research showed that this must have been a mistake.
The species was described as “occiput and back grey-reddish, the front of the head, the four limbs and the under side of the body mouse-grey and the tail black. The hands and feet have the same colour as the rest of the legs”.
The distribution range of the species is thought to extend north to the Río Paraná do Urariá, east to the left bank of the Río Abacaxis and the left bank of the upper Río Tapajós, west as far as the right bank of the Río Madeira, and south to the corridor formed between the Ríos Aripuanã-Roosevelt and Tapajós-Juruena, in the states of Amazonas and Mato Grosso.