Mary Freeman James Wood 2017 <p><i>Podostemum ceratophyllum</i><span>, commonly called Hornleaf Riverweed, occurs in mid-order montane and piedmont rivers of eastern North America, where the plant grows submerged and attached to rocks and stable substrates in swift, aerated water. Multiple studies, mostly conducted in the southern portions of the plant’s range, have shown that </span><i>Podostemum</i><span> can variously influence benthic communities in flowing waters. However, a synthetic review of the biology and ecology of the plant is needed to inform conservation, particularly because </span><i>P. ceratophyllum</i><span> is reported to be in decline in much of its range, for mostly unknown reasons. We have thus summarized the literature showing that </span><i>Podostemum</i><span> provides substantial habitat for invertebrates and fish, may be consumed by invertebrates, turtles, and other vertebrates, removes and sequesters dissolved elements (i.e., nitrogen, phosphorus, calcium, zinc, etc.) from the water column, and contributes organic matter to the detrital pool. </span><i>Podostemum</i><span> may be tolerant to some forms of pollution but appears vulnerable to sedimentation, epiphytic over-growth, and hydrologic changes that result in desiccation, and possibly increased herbivory pressure. Much remains unknown about </span><i>Podostemum</i><span>, including aspects of morphological variation, seed dispersal, and tolerance to changes in temperature and water chemistry. Nonetheless, </span><i>Podostemum</i><span> may be considered a foundation species, whose loss from eastern North American rivers is likely to affect higher trophic levels and ecosystem processes.</span></p> application/pdf 10.1016/j.aquabot.2017.02.009 en Elsevier Ecology of the macrophyte <i>Podostemum ceratophyllum</i> Michx. (Hornleaf riverweed), a widespread foundation species of eastern North American rivers article