The term “para-hypotaxis” is commonly used by Romance linguists to refer to sentences containing a proleptic dependent clause, with the main clause introduced by a coordinator. It is thus an intermediate structure between parataxis and hypotaxis; it should not be confused, however, with seemingly analogous phenomena, such as co-subordination. Traditionally considered as an idiosyncratic feature of the Old Romance languages (as well as Biblical Hebrew, Greek and Latin), para-hypotaxis has recently been discovered in at least one modern, genetically unrelated language (Swahili). This paper shows – with illustrations mostly stemming from the Zamucoan family (Ayoreo and Chamacoco) – that it is also widespread in several languages of the Chaco Boreal. The possible functional justifications of this peculiar syntactic phenomenon are discussed.