Identification. The fact that the Mataco have been identified with a series of denominations indicates the fragmentary knowledge that we have of all their different dialects and subsections. The name "Mataco" seems to be derived from Spanish montaraces (bush people), a pejorative word for those living in the little-known dry forests of the Gran Chaco.
Location. Ever since their habitat was first established, the Mataco have lived in northern and central Gran Chaco, roughly in the area between the Pilcomayo and Bermejo rivers, from the foothills of the Andes in Bolivia to the town of Las Lomitas in Argentina. This part of the Gran Chaco is known as the hottest region of South America, and, apart from a few chilly days during the period from June to August, day temperatures range between 30° and 40° C, with the average summer temperature ascending to more than 30° C. Precipitation is normally sparse, around 60 centimeters per year, which results in a semidesert climate with xerophytic vegetation.
Linguistic Affiliation. The Mataco language belongs to the Mataco-Mak'á Branch of the Macro-Guaicuruan Language Family. Lately, the latter has been associated with the Ge-Pano-Carib Language Group. Mataco has for centuries been divided into three dialects: Noctenes, Güisnay, and Véjoz, but this partition may prove insufficient.
Demography. According to official figures, there are 12,000 Mataco in Argentina and some 2,000 in Bolivia. These numbers are most certainly too low, however. In 1988 an Argentine newspaper El Nuevo Diario assessed the number of Mataco in Argentina alone to be about 60,000.