Within Camelus two species are generally accepted: C. dromedarius, the one-humped or Arabian camel or dromedary; and C. bactrianus, the Bactrian camel or two-humped camel. Biologically, the species division is not correct, as the two freely interbreed in either direction and produce fertile offspring. There are four species of new world Camelidae of which two are domesticated and two wild. The llama, L. glama, is used mainly as a pack animal, while the alpaca, L. pacos, is primarily a producer of high quality fibre. The two wild species are the guanaco, L. guanicoe and the vicuna, .
