Sporobolus virginicus, known by numerous common names including seashore dropseed, marine couch, sand couch, salt couch grass, saltwater couch, coastal rat-tail grass, and nioaka, is a species of grass with a wide distribution.

It is a spreading perennial tussock grass from 10 to 50 cm (3.9 to 19.7 in) in height. Its flowers are green or purple. It reproduces asexually by use of both stolons and rhizomes.