These plants, traditionally known as A. serpentaria var. hastata (Nutt.) Ducharte, appear distinct from typical serpentatia in their linear to lance-deltoid shape (versus ovate to ovate-oblong), with divergent basal lobes (versus just cordate), ca. 1-2 cm wide (versus 2-5 cm). Also, leaves tend to be longer. less pubescent and relatively thin-textured (W, Ladd & Thomas 2015). E. hastata occurs mostly on the southeastern Coastal Plain (from e. Tex. to Va.), generally in subhydric bottomland forests. Typical serpentaria has a more widespread south-central range, typically in mesic to subxeric upland forests. Narrow leaves may be an adaptation to reduce egg-laying by the Eastern Pipe-vine Swallowtail butterfly, which uses leaf shape as a search image (FNA 3).