There are several closely related species such as Sagittaria cuneata Sheldon, with a minute beak to the achene, which is erect over the ventral wing; Sagittaria pubescens Muhlenberg, which is strongly pubescent; Sagittaria graminea Michaux, which has long-petioled, linear, lanceolate or elliptical leaf blades, acute at both ends, and much smaller flowers than S. latifolia, and other less abundant species. A nearly related genus is Alisma, represented in our range by the very common Alisma subcordatum Rafinesque (American Water Plantain), with oblong, elliptic, oval or ovate leaf blades which are cuneate, truncate or cordate at the base, the flowering scapes rather tall, bearing numerous branches and pedicels in whorls of three to ten, with very small, white flowers. Like most other members of the Alismaceae, it inhabits shallow water or muddy places.