The definition of the genus Jupiaba is based on six putative synapormorphies related to the structures of pelvic girdle and adjacent musculature (Zanata, 1997; Lima & Zanata, 2005). Jupiaba was proposed by Zanata (1997) to include 21 characid species primarily described in the genera Astyanax Baird & Girard or Deuterodon Eigenmann . More recently, Lima & Zanata (2005) described an additional species, Jupiaba poekotero , from rio Negro drainage. Therefore, Jupiaba currently comprises 22 valid species, widely distributed throughout the rio Amazonas, rio Essequibo, and rio Oiapoque drainages, plus one single species from the rio Paraguay drainage (Lima et al., 2003; Eschmeyer, 2006). However, the study of Jupiaba samples deposited at the Fish Collection of the Laboratório de Ictiologia Sistemática da Universidade Federal do Tocantins (acronym UNT) revealed the presence of an undescribed Jupiaba species from the rio Tocantins drainage; the description of this species is provided below.