The Podostemacea are a unique group of strictly aquatic rheophytic macrophytes, that grow attached to stable substrates throughout South and Central America and Eastern North America, as well as in Africa, Australia, and southeastern Asia. The plants attached to stable substrates and specialize on waterfall, cascades, and other similar swift-water habitats. Eastern North America has only one species of Podostemaceae, Podostemum ceratophyllum, which has been described as a foundation species of eastern North American rivers due to the plant’s positive influence on macroinvertebrate diversity and abundance, and correlations with some species of fish. However, observations of the plant suggest that when the plant is stressed, it can easily be detached from benthic substrates, possibly leading to rapid local extirpation. Previous observational studies have suggested the Podostemaceae may use cyanobacteria to attach to substrates. Here I report the results of a study on P. ceratophyllum that used phylogenetics to assess the microbial community of the haptera (the structure that attaches the plant to the substrate). We found that the haptera community was diverse, and while cyanobacteria were present on the haptera of some plants, other bacteria and archaea were also present, including nitrogen-fixing taxa. Our results indicate a more complicated relationship between the Podosteamceae and the biofilm community than had previously been suggested, providing insight into how environmental stressors may affect these plants.