They are small wading birds confined to remote Pacific islands of French Polynesia.

The genus Prosobonia was introduced in 1850 by the French naturalist Charles Lucien Bonaparte with the Tahiti sandpiper, as the type species.

[1][2] Bonaparte did not explain the etymology of the genus name but it is probably from the Ancient Greek prosōpon meaning "mask" or "face".

The first of these was almost certainly more closely related to the Tahiti and Moorea populations than to the Tuamotu sandpiper, but the exact nature of their relationship is unlikely to be resolved anytime soon.

The latter, a distinct species with long legs and short wings,[7] became extinct only about 1000 years after the Mangaia form, some time after 1200.