A vegetative population of Cryptocoryne (Araceae), introduced at a Florida spring, appeared to represent three closely related species in the C. beckettii complex: C. beckettii Thw. ex Trimen, C. wendtii de Wit and C. undulata Wendt. Individuals of C. undulata were true to type and could be delineated at the site. Intergradation of diagnostic features was common in others, upon transplanting and flowering. While some transplants produced spathes characteristic of either C. wendtii or C. beckettii, intermediates between the two species were common. Neither C. beckettii nor C. wendtii could be delineated at the site. The seclusion of the stream and the integrity of native plant communities have likely prevented dispersal downstream.