Revision of aloricate Oligotrichea

The Oligotrichea (Protozoa, Ciliophora) are the last class of the Spirotricha which requires a fresh revision. Since the cytological features of the house-forming Tintinnina are almost unknown, they are excluded from the planned monograph. The aloricate Oligotrichea are not only comparatively better known than the tintinnids but they also often dominate the marine and limnetic microplankton. The 127 species descriptions compiled in the monographs from Maeda & Carey (1985) and Maeda (1986) were based on live and preserved material. These guides therefore do not comprise information on species-specific features obtained by modern techniques, e.g., protargol impregnation (staining with silver proteinate) and scanning electron microscopy. Since 1986, 75 new species of aloricate Oligotrichea have been described and 43 insufficiently known ones have been redescribed applying the modern methods. A recent phylogenetic approach based on morphologic features necessitated the establishment of three new families and four new genera within the aloricate Oligotrichea and a revision of the classification. Furthermore, several hundreds of papers on the ecology, cell division, conjugation, resting cysts, gene sequence analyses of these ciliates have been published in a wide variety of journals. The fragmented publication of the data, i.e., the lack of a unifying guide and key to the species of the aloricate Oligotrichea, causes serious problems, concerning (i) the species identification, (ii) the assessment of their biodiversity and role in the food web dynamics, and (iii) the estimation of their spatial distribution. The main aim of the proposed project is the development of a monograph on the aloricate Oligotrichea, including (i) a description of the general morphology, biology, phylogeny, classification, and methodology and (ii) the descriptions of the families, genera, and species by providing all literature data and line drawings. Additionally, hundreds of ecological paper will be studied for an estimation of the spatial distribution and further autecological data. Two keys will guide to the species: one based on live and protargol-impregnated specimens, the other on fixed material. A draft of the monograph comprising ~ 300 pages with rough descriptions and ~ 1,200 line drawings of the more than 200 species has already been developed. A literature data bank with more than 25,000 data set has also been established by the applicant, providing an easy access to the species descriptions published in several hundred publications. The second objective of the planned project is the description of further new or insufficiently known Oligotrichea species contained in available material from European coastal waters. The aloricate Oligotrichea do not provide many morphological characters for phylogenetic studies compared to the related stichotrichs (e.g., Stylonychia) or hypotrichs (e.g., Euplotes). Ultrastructural investigations will thus be performed to search for new features to be included into the cladistic analyses. Parallel, the small subunit rRNA gene of further aloricate Oligotrichea will be sequenced in a well-tried cooperation with Canadian colleagues, as the gene tree currently comprise too few species to elucidate the genealogies. All results will also be included into the monograph. The planned monograph will thus serve as an essential guide to the taxa, without referring back to the original literature, and a valuable tool for all who deal with ciliates, i.e., not only for taxonomists but also ecologists, physiologists, and molecular biologists.

The Oligotrichea (Protozoa, Ciliophora) are the last class of the Spirotricha which requires a fresh revision. Since the cytological features of the house-forming Tintinnina are almost unknown, they are excluded from the planned monograph. The aloricate Oligotrichea are not only comparatively better known than the tintinnids but they also often dominate the marine and limnetic microplankton. The 127 species descriptions compiled in the monographs from Maeda & Carey (1985) and Maeda (1986) were based on live and preserved material. These guides therefore do not comprise information on species-specific features obtained by modern techniques, e.g., protargol impregnation (staining with silver proteinate) and scanning electron microscopy. Since 1986, 75 new species of aloricate Oligotrichea have been described and 43 insufficiently known ones have been redescribed applying the modern methods. A recent phylogenetic approach based on morphologic features necessitated the establishment of three new families and four new genera within the aloricate Oligotrichea and a revision of the classification. Furthermore, several hundreds of papers on the ecology, cell division, conjugation, resting cysts, gene sequence analyses of these ciliates have been published in a wide variety of journals. The fragmented publication of the data, i.e., the lack of a unifying guide and key to the species of the aloricate Oligotrichea, causes serious problems, concerning (i) the species identification, (ii) the assessment of their biodiversity and role in the food web dynamics, and (iii) the estimation of their spatial distribution. The main aim of the proposed project is the development of a monograph on the aloricate Oligotrichea, including (i) a description of the general morphology, biology, phylogeny, classification, and methodology and (ii) the descriptions of the families, genera, and species by providing all literature data and line drawings. Additionally, hundreds of ecological paper will be studied for an estimation of the spatial distribution and further autecological data. Two keys will guide to the species: one based on live and protargol-impregnated specimens, the other on fixed material. A draft of the monograph comprising ~ 300 pages with rough descriptions and ~ 1,200 line drawings of the more than 200 species has already been developed. A literature data bank with more than 25,000 data set has also been established by the applicant, providing an easy access to the species descriptions published in several hundred publications. The second objective of the planned project is the description of further new or insufficiently known Oligotrichea species contained in available material from European coastal waters. The aloricate Oligotrichea do not provide many morphological characters for phylogenetic studies compared to the related stichotrichs (e.g., Stylonychia) or hypotrichs (e.g., Euplotes). Ultrastructural investigations will thus be performed to search for new features to be included into the cladistic analyses. Parallel, the small subunit rRNA gene of further aloricate Oligotrichea will be sequenced in a well-tried cooperation with Canadian colleagues, as the gene tree currently comprise too few species to elucidate the genealogies. All results will also be included into the monograph. The planned monograph will thus serve as an essential guide to the taxa, without referring back to the original literature, and a valuable tool for all who deal with ciliates, i.e., not only for taxonomists but also ecologists, physiologists, and molecular biologists.