Psammon (from Greek "psammos", "sand"[1]) is a group of organisms inhabiting coastal sand moist — biota buried in sediments. Psammon is a part of water fauna, along with periphyton, plankton, nekton, and benthos.[2] Psammon is also sometimes considered a part of benthos due to its near-bottom distribution.[3] Psammon term is commonly used to refer to freshwater reservoirs such as lakes.[2][4]