Symplegma is a genus of colonial sea squirts within the class Ascidiacea, commonly found in shallow tropical and subtropical marine environments. Species of Symplegma form thin, encrusting or lobed colonies composed of numerous small zooids embedded in a shared, often translucent tunic. The colonies may appear sheet-like or slightly raised and are frequently brownish, purplish, gray, or translucent, sometimes blending closely with the substrate. Each zooid has separate incurrent and excurrent siphons and feeds by filtering plankton and organic particles from the water through a well-developed pharyngeal basket. Like other ascidians, Symplegma species begin life as free-swimming tadpole larvae that settle and metamorphose into sessile adults. They commonly grow on rocks, mangrove roots, coral rubble, pilings, and boat hulls, contributing to biofouling communities while playing an ecological role in water filtration and nutrient cycling.