An elater is a cell (or structure attached to a cell) that is hygroscopic, and therefore will change shape in response to changes in moisture in the environment. Elaters come in a variety of forms, but are always associated with plantspores. In many plants that do not have seeds, they function in dispersing the spores to a new location. Mosses do not have elaters, but peristome which also change shape with changes in humidity or moisture to allow for a gradual release of spores.
"Elaters" is also used as a common name for the Elateridae (click beetles). For the click beetle genus, see Elater (beetle).
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