Noun
A South American mammal (Auchenia huanaco), allied to the llama, but of larger size and more graceful form, inhabiting the southern Andes and Patagonia. It is supposed by some to be the llama in a wild state.
Source: Webster's dictionaryAlpacas are descended from wild vicuna ancestors, while domesticated llamas are descended from wild guanaco ancestors, though a considerable amount of hybridization between the two species has occurred. Source: Internet
The guanaco and vicuña are wild, the former being endangered, and of a nearly uniform light-brown color, passing into white below. Source: Internet
They certainly differ from each other, the vicuña being smaller, more slender in its proportions, and having a shorter head than the guanaco. Source: Internet