Vaejovis intrepidus atrox Hoffmann, 1931, is newly synonymized with T. Three new species of Thorellius are described: Thorellius tekuani Thorellius wixarika and Thorellius yuyuawi. Thorellius cristimanus ( Pocock, 1898) and Thorellius intrepidus (Thorell, 1876) are redescribed and their type localities discussed and clarified. The monotypic Balsateres and Kuarapu are redescribed. In the present contribution, all except Kochius, treated elsewhere, are revised.
Four genera formed a monophyletic group, referred to as the Kochius clade, in the phylogeny of the North American vaejovid scorpion subfamily Syntropinae Kraepelin, 1905: Balsateres González-Santillán and Prendini, 2013 Kochius Soleglad and Fet, 2008 Kuarapu Francke and Ponce-Saavedra, 2010 and Thorellius Soleglad and Fet, 2008.
