Clover grass is a type of seagrass found mainly in the Caribbean region, forming dense underwater meadows in some areas, yet elsewhere the species is rare and sparse, limited to seven locations and continuing to decline.

The biology of clover grass is relatively unknown, but it performs an ecological role as food source for the vulnerable West Indian manatee and shelters some species of mussels and fish. Clover grass is highly susceptible to the effects of polluted water and heavy storms, while a large meadow in Belize is in rapid decline due to both the growing tourist industry and eutrophication. Seagrasses worldwide are contaminated by micro-plastic particles; a 2020 study found that each blade of seagrass examined in a bed in the Orkney Islands had an average of four micro-plastic particles on its surface, posing severe risks to the ecology that seagrasses support.