ABSTRACT New data about several aspects of the biology of scorpions of genus Brachistosternus of the Atacama Desert are provided. Predatory techniques on tenebrionid larvae, and large spiders in their burrows are described, as well as the method used to transport large preys. The habitat of Brachistosternus mattonii Ojanguren-Affilastro 2005, by the tide line, is described for the first time. Finally a new type of pedipalp macroseta of Bothriuridae is described.