
New Populations of the Rheophytic Macrophyte Podostemum ceratophyllum Michx. (Hornleaf Riverweed) in West Virginia
Podostemum ceratophyllum (Hornleaf riverweed) is a macrophyte that inhabits swift-water rivers with stable substrates and abundant light in montane and piedmont ecoregions of eastern North America. Within these habitats, P. ceratophyllum is considered a foundation species because the plant can strongly influence community structure by increasing habitat complexity for macroinvertebrates and fishes, and facilitates resources cycling via elemental sequestration, herbivory, and detrital pathways. Currently, the USDA and NatureServe recognize P. ceratophyllum as a conservation concern in some states, but the plant’s status remains uncertain in many other states. In West Virginia, P. ceratophyllum is considered imperiled (S2) by the West Virginia Natural Heritage Program. The most recent records were collected in 1998, while other populations have not been confirmed since the late 1800s. To expand our current understanding of the distribution of P. ceratophyllum in West Virginia, we surveyed six historical sites and 34 new sites between 2015–2019. Four historical