Great Waterleaf is one of the more common Hydrophyllum spp. within the state and its flowers are the most attractive. This species has hairy stems and calyxes, and some of its leaves are maple-shaped. A distinctive characteristic consists of the small recurved appendages between the teeth of the calyx, hence the 'appendiculatum' in the scientific name. Other Hydrophyllum spp. lack these strongly recurved appendages and they have less showy flowers. The species Hydrophyllum virginiana (Virginia Waterleaf) and Hydrophyllum canadense (Canada Waterleaf) have smooth stems and hairless calyxes, while Hydrophyllum macrophyllum (Large-Leaved Waterleaf) lacks cleft orbicular leaves with a maple-like appearance. The leaves of this latter species are always longer than broad, and they are pinnately divided to an even greater extent than the lower leaves of Great Waterleaf.