Two new species of Heteranthera (Pontederiaceae) in North America

  • Charles N. Horn Department of Biology, Newberry College


Two new species are here described as segregates from Heteranthera multiflora. Heteranthera missouriensis sp. nov. has 5–13 flowers on an elongate floral axis, lavender to purplish flowers, a smaller perianth with the tube 3–5 mm long and lobes 3–4.5 mm long; it is common in the southern Great Plains of North America. Heteranthera pauciflora sp. nov. has 3–6 flowers on a shortened floral axis, commonly enclosed by the subtending spathe, white to light lavender flowers with the tube 8–10 mm long; it is known from the Atlantic coast from New Jersey to North Carolina. A taxonomic key to all species of the genus in North America, and a modified description of Heteranthera multiflora, are provided.


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How to Cite
Horn, C. N. (2020). Two new species of Heteranthera (Pontederiaceae) in North America. Journal of the Botanical Research Institute of Texas, 14(1), 1-8.