Developmental and Structural Section
Meis Chormanski, Theresa , Richards, Jennifer .
Morphology and anatomy of three common Everglades Utricularia species: U. gibba, U. subulata, and U. cornuta.
OF the approximately 475 carnivorous plant species, over 200 belong to the genus Utricularia, the bladderworts. Ten species of Utricularia are native to South Florida and seven are found in Everglades National Park. These Utricularia species are important components of local wetlands, comprising three of the 15 most common species in the 1999 and 2005 EPA REMAP plant surveys. Despite their abundance, we do not have a good understanding of the basic biology of Everglades Utricularia species. Utricularia species have lost the typical angiosperm structure, are flexible in their growth patterns, and have predatory or mutualistic interactions with organisms in their traps. These characteristics complicate understanding their position in local plant communities; increased knowledge of their biology will contribute to understanding community structure and ecosystem processes in the Everglades. We analyzed the morphology of U. gibba, U. cornuta, and U. subulata using dissecting, compound and scanning electron microscopy. Paraffin-embedded stained sections were used to examine internal anatomy. U. gibba is classified as an affixed aquatic while U. cornuta and U. subulata are terrestrial but all three can occur in submerged benthic or floating periphyton mats. Additionally, the three are commonly confused because their morphology exhibits a high degree of plasticity. Vegetatively, U. gibba consists of mat-forming stolons from which filiform, dichotomously branching leaves arise. The leaves bear traps, and axillary buds are often present. Although phylogenetically divergent, U. cornuta and U. subulata are morphologically similar. These two species produce stolons with linear green leaves and “rhizoids” or thin, non-photosynthetic organs that anchor the plant in the substrate. Unlike U. gibba, traps are found on all plant organs. For this study, the range of plasticity was determined by quantifying the vegetative characteristics of field-collected plants. All species were plastic in their growth forms with morphological variation correlating to nutrient availability.
Log in to add this item to your schedule
1 - Florida International University, Deparment of Biological Sciences, 11200 SW 8th St., Miami, Florida, 33199, USA
Presentation Type: Oral Paper:Papers for Sections
Location: 303/Bell Memorial Union
Date: Monday, July 31st, 2006
Time: 8:15 AM