The Tahiti sandpiper was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae.

[3] Gmelin based his description on the "white-winged sandpiper" that had been described and illustrated in 1785 by the English ornithologist John Latham from a specimen collected in Tahiti.

[5][6] Bonaparte did not explain the etymology of the genus name, but it is likely from the Ancient Greek prosōpon meaning "mask" or "face".

[7] Based on Zusi & Jehl (1970):[8] A small (some 18 cm long), plain-colored sandpiper, brown below, darker above, with a white wing patch.

Bill blackish, lower mandible slightly paler, pointed, thin and short, rather like in an insectivorous passerine than a wader.

The Moorea Sandpiper—of which another painting, by William Ellis, and a plate by John Webber, supposed to depict the other specimen, constitute all remaining evidence—differs in the color of wings and head.

It is not likely that they will be studied anytime soon; a scientific description would require either successful extraction and analysis of DNA from both the bones and the Leiden specimen (which would risk being damaged during extraction of the tissue sample), or the collection of a sufficient amount of material from Tahiti or Moorea to determine the Mangaia bird's affiliation by analysis of the osteology.