Eleocharis acicularis is a species of spikesedge known by the common names needle spikerush and least spikerush. It is widespread across Europe, central and southeastern Asia, North America and northeastern South America as far south as Ecuador. It is also found in Australia, where it is probably an introduced species. Eleocharis acicularis is sold commercially as a aquascape plant suitable for inclusion in artificial aquatic environments. It thrives with plenty of light and a high concentration of carbon dioxide.