The sites of Kossom Bougoudi (KB) and Kollé (KL) are intermediate in age between the Sahelanthropus sites of Toros Menalla and the Australopithecus sites of Koro Toro, and their bovid faunas are also intermediate in composition and stage of evolution. Four new taxa are erected. The hippotragine Tchadotragus fanonei nov. sp. is more derived than the type-species of the genus, from Toros Menalla. Kobus ammolophi nov. sp. is also clearly related to the most common reduncine of the latter sites, rather than with other African forms. However, Jamous kolleensis nov. gen. nov. sp., a new bovine with extremely divergent, horizontal horn-cores, is unrelated to other Chadian Bovini. The KB and KL assemblages document the gradual replacement of hippotragines by alcelaphines in Northern Chad, but it is not necessarily linked with environmental change, as all Chadian assemblages virtually lack indicators of bush or woodland like Tragelaphini and Aepyceros. In spite of a significant endemic component, the KB and KL Bovidae compare best with some of those from Sahabi in Libya, confirming North-South connections.