an Entity references as follows:
Plecturocebus is one of three genera of titi monkeys. Historically, these monkeys were monogeneric, being placed in a single genus: Callicebus Thomas, 1903. Owing to the great diversity found across titi monkey species, a new genus-level taxonomy was proposed in 2016 that recognises three genera within the subfamily Callicebinae; Plecturocebus Byrne et al., 2016 for the Amazonian and Chaco titis of the moloch and donacophilus groups; Cheracebus Byrne et al., 2016 for the species of the torquatus group (Widow titis); and Callicebus Thomas, 1903 sensu stricto, for species of the Atlantic Forest personatus group.