![banner3 Molluscs of Tasmania](https://molluscsoftasmania.org.au/wp-content/uploads/2017/07/banner3.jpg)
Rissoidae: Onoba (Ovirissoa) pertumida (May, 1916) (‘swollen rice-shell’)
Synonym(s): pertumida May, 1916.
Typical shell-length 2.2 mm. Lives subtidally and offshore. Native. Endemic to southeastern Australia (TAS only).
Classification
Class: Gastropoda
Subclass: Caenogastropoda – Sorbeoconcha
Order: Hypsogastropoda – Littorinimorpha
Superfamily: Rissooidea
Family: Rissoidae
Genus: Onoba
Localities for Onoba pertumida
![species image](https://molluscsoftasmania.org.au/wp-content/uploads/2017/07/no_image.jpg)
![locality map](https://molluscsoftasmania.org.au/wp-content/uploads/2017/09/Onoba-pertumida.jpg)