The Family Rheidae is a group of birds found in South America. They are commonly referred to as rheas and are similar in appearance to ostriches and emus. Some synonyms for the Family Rheidae include rheids and American rheas. These flightless birds have long legs, small wings, and large bodies. They are primarily herbivores and are known for their distinctive mating behaviors. Rheas are important to the ecosystem of South America and are an important part of indigenous cultural traditions. Despite facing threats from habitat destruction and hunting, rheas continue to thrive in their native South American habitats.