Macrauchenia (literally "Big Neck") was a long-necked and long-limbed, three-toed South American ungulate mammal, typifying the order Litopterna. The oldest fossils date back to around seven million years ago, and M. patagonica disappears from the fossil record during the late Pleistocene, around 10 thousand years ago. M. patagonica was the best known member of the family Macraucheniidae, and is known only from fossil finds in South America, primarily from the Lujan Formation in Argentina. The original specimen was discovered by Charles Darwin during the voyage of the Beagle. In life, Macrauchenia resembled a humpless camel with a short trunk, though it is not closely related to either camels or proboscideans.