Hunt for early diverged stramenopiles and construction of taxonomic system

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The following results were obtained during the period of this research :1. Undescribed two heterotrophic stramenopiles were discovered and reported as two new genera, Wobblia and Placidea. Molecular analyzes indicated these organisms diverged before emergence of the heterokont chromophytes, and that they form a clade independent from any known clades of the stramenopiles. A new class Placididea or Placidiophyceae was proposed.2. A new class of heterokont chromophytes, Pinguiophyceae, was proposed. This class is biochemically characterized : all the members so far known produce rich omega 3 fatty acids.3. Non-photosynthetic stramenopiles, Ptendomonas and Ciliophrys, were revealed to have chloroplast encoded gene rbcL. The gene was almost intact and unlikely a pseudogene. In Pteridomonas, the presence of vestigial chloroplast was confirmed with the electron microscope.4. Three orders of the class Dictyochophyceae were investigated with EM and molecular data (18S rDNA and rbcL). Taxonomic characters appeared in previously published articles were reevaluated based on cladistics of using morphological (LM and EM) and behavioral characters, and diagnostic characters of genera were considered. Practical guide for classification of Pedinellales genera was proposed.5. An amoeboid alga presumably a primitive member of the class Dictyochophyceae was discovered and examined. This organism formed a clade with Sulcochrysis described as incertae cedis. A proposal of a new order Sulcochrysidaies is under process.6. An amoeboid alga that produce biflagellate swimming cells in the life cycle was discovered. Comparison of this alga with other members of the Dictyochophyceae suggested that primitive state of the class was biflagellate and possession of typical stramenopile flagellar apparatus.The results obtained allowed to reconstruct character evolution presumably occurred in major clades of the stramenopiles.