A Survey of the Land Snails of Kosrae (Caroline Islands, Micronesia) Including the Rediscovery of EndemicDelos oualanensis(Pease, 1866) (Mollusca: Pulmonata: Rhytididae)

Abstract

ABSTRACT This is the first published documentation of the land snails from Kosrae Island (eastern Caroline Islands, Micronesia; ∼ 5.3°N, 163°E). Timed hand collecting in leaf litter and emergent vegetation over the course of five days yielded 15 species in 13 gastropod families, including important collections of Delos oualanensis (Rhytididae) and Sinployea kusaieana (Charopidae), which had not been collected since the last survey of Kosrae in the 1930s. We did not recover evidence for in situ diversification in Kosrae — rather, the fauna seems to be a subset of the general Micronesian fauna (especially that of Pohnpei), with endemic species most likely having sister species off-island. An exotic veronicellid slug, and several snails that are widespread and possibly introduced were found, but no giant African land snails (Achatina fulica) were found. Due to its position as the eastern-most high island in Micronesia, Kosrae is an important part of our understanding of both the pre-anthropogenic assembly of...