The sparsely settled tropical grasslands of southern venezuela and eastern colombia are called

The answer is Llanos. Llanos or in Spanish it is called plains. These are wide grasslands stretching across northern South America and inhabiting western Venezuela and northeastern Colombia. The Llanos have a region of approximately 220,000 square miles, surrounded by the Andes Mountains to the north and west, the Guaviare River and the lower Orinoco River and the Guiana Highlands to the east, and the Amazon River basin to the south.