Vitta usnea is a species of freshwater snail with an operculum, an aquatic gastropod mollusk in the family Neritidae, the nerites.

[1] Vitta usnea, (common name olive nerite) is a euryhaline organism living at salinities ranging from 0 to 19 ppt.

It ranges from north Florida on the Atlantic Coast through the coastal waters of the Gulf of Mexico and the Caribbean Sea to Trinidad (Russell, 1941).

Vitta usnea lives in shallow protected bays from just above high water to approximately 1.5 meters in depth where it is found on sea grasses, emergent marsh plants, rocks, and stumps.

It is known to climb up marsh grass blades at high tide to avoid predators.