Geology topics
Publications and source records attributed to C.C. Jacono.
Naturalized populations of the Asian amphibious species Rotala rotundifolia are documented for three peninsular Florida counties. Distinguishing characters and a comment on invasive potential are also provided.
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.
Abstract not supplied at this time
A non-native species of Scleria, S. lacustris is reported from six counties and three major hydrologic regions in Florida. Biogeography and habitat in Florida are addressed. A description, key features and illustration are presented.
Hydrilla (Hydrilla verticillata (L.f.) Royle), an invasive aquatic weed, continues to spread to new regions in the United States. Two biotypes, one a female dioecious and the other monoecious have been identified. Management of the spread of hydrilla requires understanding the mechanisms of introduction and transport, an ability to map and make available information on distribution, and tools to distinguish the known U.S. biotypes as well as potential new introductions. Review of the literature and discussions with aquatic scientists and resource managers point to the aquarium and water garden plant trades as the primary past mechanism for the regional dispersal of hydrilla while local dispersal is primarily carried out by other mechanisms such as boat traffic, intentional introductions, and waterfowl. The Nonindigenous Aquatic Species (NAS) database is presented as a tool for assembling, geo-referencing, and making available information on the distribution of hydrilla. A map of the current range of dioecious and monoecious hydrilla by drainage is presented. Four hydrilla samples, taken from three discrete, non-contiguous regions (Pennsylvania, Connecticut, and Washington State) were examined using two RAPD assays. The first, generated using primer Operon G17, and capable of distinguishing the dioecious and monoecious U.S. biotypes, indicated all four samples were of the monoecious biotype. Results of the second assay using the Stoffel fragment and 5 primers, produced 111 markers, indicated that these samples do not represent new foreign introductions. The differences in the monoecious and dioecious growth habits and management are discussed.
[No abstract available]