﻿AbstractThe relationship between the generaColasiaKoch, 1965 andBelousoviaMedvedev, 2007 within the tribeBlaptiniis discussed, and a new synonymy is proposed:BelousoviaMedvedev, 2007,syn. nov.ofColasiaKoch, 1965. As a result, three new combinations are established:Colasiahelenae(Medvedev, 2007),comb. nov.,C.kabakiintermedia(Medvedev, 2007),comb. nov., andC.kabakikabaki(Medvedev, 2007),comb. nov.ColasiaakisoidesKoch, 1965 is redescribed, and a lectotype is designated. Three new species of the genusColasiaare described and illustrated from China:C.bijicasp. nov.(Guizhou),C.medvedevisp. nov.(Yunnan), andC.pilosasp. nov.(Yunnan). A distribution map and a key to species of the revised genusColasiaare presented.