A new species of the Indo-West Pacific gastropod Iravadia s.s. is described from the late Oligocene (Chattian) of southwestern France, the earliest record of the genus. Iravadia dolini n. sp. is close to the recent species I. angulata (Laseron, 1956) but has a shorter spire and smaller ovate aperture not angled. This discovery suggests that the adaptation of Iravadia Blanford, 1867 to brackish waters (mangroves subenvironment?) probably occurred earlier than previously suspected.
Mollusca, Gastropoda, Rissooidea, Iravadia s.s., Oligocene, Cenozoic, brackish-water, mangrove, southern France, new species