Salvinia, scientifically named Salvinia molesta, is a floating fern with paired, oval leaves covered in tiny water-repellent hairs that give the plant a velvety texture. These hairs form a distinctive egg-beater shape under magnification, allowing Salvinia molesta to remain buoyant and effectively shed water. Native to South America, it spreads across still or slow-moving waters such as ponds, canals, and wetlands.

A notable trait of Salvinia molesta is its rapid vegetative reproduction—fragments expand into thick mats that can block sunlight, restrict gas exchange, and severely impact native aquatic communities. Though rootless, it produces submerged leaf structures that mimic roots. Its dense growth can halt boat movement and disrupt ecosystems, making Salvinia molesta one of the world’s most problematic aquatic invasives. Despite this, its unusual floating architecture makes it visually distinctive among water plants.