as do the larvae of the moth Spodoptera pectinicornis from Thailand. Both are proving to be useful tools in the management of Pistia stratiotes through the experimental recovery of benthic communities with hypoxic conditions. Native range The center of origin of Pistia stratiotes remains uncertain. However, the plant is thought to be native to South America or Africa. Described in Egyptian hieroglyphics and reported by Greek botanists, Dioscorides and Theophrastus, in the Nile River, the plant suggests an African origin. In addition, the co-evolution of Pistia stratiotes with various insects native to Brazil and Argentina, such as the water lettuce weevil, proposes a South American origin. It is a common aquatic plant in the southeastern United States, particularly in Florida. A more recent argument for nativity in Florida notes that it was recorded by botanist, William Bartram, in the St. Johns River basin in 1765, and fossil specimens dating back to the late Pleistocene (~12,000 BP) and early Holocene (~3,500 BP) period are reported from Florida. Yet, the rationale of southeastern, North American nativity remains controversial as disagreeing botanists claim the Spanish may have indirectly introduced into the plant into Florida's basins from their ship ballast. Fossil record Pistia-like plants appear in the fossil record during the Late Cretaceous epoch in rock strata from the western interior of North America. They were first described as †Pistia corrugata by Leo Lesquereux in 1876 based on specimens from the Almond Formation of Wyoming (late Campanian age). However, based on more complete specimens from the Campanian Dinosaur Park Formation of southern Alberta, Canada, and other areas, they were redescribed as a separate genus, †Cobbania, primarily due to differences in leaf morphology. Younger fossils attributed to Pistia stratiotes have described from Eocene strata in the southeastern United States, and 350 fossil seeds of †Pistia sibirica have been described from middle Miocene strata of the Fasterholt area near Silkeborg in Central Jutland, Denmark. Fossils of this species have also been described from the Oligocene and Miocene of Western Siberia and from the Miocene of Germany. A specimen of Pistia stratiotes from the Florida peninsula dating from at least 3,550 years Before Present, as well as a report of early Holocene Pistia pollen from a lake in Florida, have cast doubt on the claim that Pistia stratiotes is not native to the southeastern United States. Uses Consumption While considered edible, Pistia stratiotes is not palatable as