What is "buff-breasted sandpiper"

The buff-breasted sandpiper (Tryngites subruficollis) is a small shorebird. Tryngites is from Ancient Greek trungas, a white-rumped wading bird mentioned by Aristotle but not further identified. The species name subruficollis is from Latin sub, "near to" and collum, "neck". It is a calidrid sandpiper and currently considered to be the only member of the genus Tryngites. It may belong in the genus Calidris itself, or more precisely with the small species thereof that could possibly be split into a distinct genus. Depending on whether this would include the curlew sandpiper or not, the name Erolia would or would not, respectively, apply.