This species can be distinguished from all other Lord Howe Island tateids by its broadly ovate shape and brown colour.
The penis with swollen base, distal third simple, narrow, tapering, bent back on basal portion when at rest. The lack of a penial flange is unique for the Lord Howe Island species of Fluviopupa.
Fluviopupa oscitans (Iredale, 1944)
Class Gastropoda
Infraclass Caenogastropoda
Order Littorinida
Suborder Rissoidina
Superfamily Truncatelloidea
Family Tateidae
Genus Fluviopupa Pilsbry, 1911.
Original name: Fluviorissoina oscitans Iredale, 1944. In Iredale, T. (1944). The land Mollusca of Lord Howe Island Australian Zoologist 10: 299-334.
Type locality: Little Slope, Lord Howe Island.
Synonym: Fluviorissoina obesa Iredale,1944.
The only Lord Howe Island tateid which lives almost exclusively on permanently wet vertical rock surfaces.
Southern mountains of Lord Howe Island.
This species was was tentatively assigned to Potamopyrgus by Ponder (1982) and but has recently been shown to belong to Fluviopupa (Ponder et al. 2023).
Ponder, W. F. (1982). Hydrobiidae of Lord Howe Island (Mollusca: Gastropoda: Prosobranchia). Australian Journal of Marine and Freshwater Research 33: 89-159.
Ponder, W. F., & Köhler, F. (2024). A review of the relationships of the Tateidae of Lord Howe Island. Molluscan Research, pp. 1–7. https://doi.org/10.1080/13235818.2024.2355680
