Potamogeton clystocarpus is a rare species of flowering plant in the pondweed family known by the common name Little Aguja pondweed. It is endemic to Texas in the United States, where it is known only from one river canyon in Jeff Davis County. There is a single population of the aquatic plant in Little Aguja Creek, and it has never been seen anywhere else. This is a federally listed endangered species of the United States.
This aquatic plant has a stem growing up to 57 centimeters long, varying ...