Ultrastructural Description of the Family Metacystidae (Prostomatida, Ciliophora, Protista) and a Phylogenetic Analysis of the Prostomate Ciliates

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WPC 2 B V P Z Courier 10cpi ? x x x , k x 6 X @ 8 ; X @ HP Laserjet (25-in-one, Network) HPLASEII.PRS x @ , t 0 OpX @ 2 2 @ Z cpi 3| x Sj x 6 X @ 8 ; X @ HP DeskJet 500 HPDES500.PRS x @ x X , , 0 FX @ 2 , F P #| x 9305925 Lipscomb During the past two decades many ultrastructural; descriptions of ciliate genera provided new information that inspired reviews and revisions of ciliate systematics. However, there have been only a few publications on the ultrastructural morphology of ciliates in the order Prostomatida, and no work at all on the suborder Prostomatina. Because these ciliates have been proposed to be among the most primitive ciliates, a thorough morphological and taxonomic analysis of them is necessary before a stable classification of the phylum Ciliophora can be achieved. The primary objective of this proposal is to extend the taxonomic scope of the PI's previous studies on the ciliates to include the prostomate family Metacystidae Kahl 1926 by focussing on an ultrastructural description of all the genera in the family, a description of the morphogenesis of a species of the genus Metacystis , and a cladistic phylogenetic analysis of the family's relationship to other prostomial ciliates. The cladistic analysis will allow testing of hypotheses about the supposedly primitive evolutionary position of prostomate ciliates. The broader significance of the proposed investigation is that understanding the diversity and phylogeny of ciliate groups will provide insight into basic evolutionary principles acting on both the single eukaryotic cell and on microbial organisms. In analyzing the complex ultrastructural features o f these ciliates, problems and limitations of various methods for ordering multistate characters will be explored. Details of this methodological exploration should be of broad value to systematists working with different groups of organisms and confronting problems with multistate character ordering. %%% Ciliate protozoa play an important role in temporate costal wetlands as predators on bacteria, algae, other protozoa and small invertabrates in the decomposer food chain. But the relationships of most of these ciliates are poorly understood. This project will utilize detailed ultrastructural analysis to address questions of relationships of the family Metacystidae, a group considered to be very basal and therefore critical in understanding relationships of these important protozoa.