Aquatic hyphomycetes were discovered 50 years ago by C.T. Ingold. They remained a relatively obscure group until their role as intermediaries between deciduous leaves and stream invertebrates was established some 20 years ago. This book, for the first time, provides a comprehensive summary and critical evaluation of the biology and ecology of these organisms. Aspecial effort was made to evaluate the potential and actual insight that have been or will be derived from work in related disciplines such as the ecology of other fungal groups, stream ecology, or population ecology. The topics treated include the basic life history of the fungi and the potential role of wood, a discussion of how the fungi have adjusted to life in running water, their interactions with invertebrates, the attachment and germination of their spores, what is known about sexual reproduction, how water chemistry may influence their distribution and activity, how they react to human degradation of their environment, and a summary of the research done on the Indian subcontinent. The volume is of special interest to mycologists and stream ecologists and should facilitate the entry of new workers into this exciting area.

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1 Research on Aquatic Hyphomycetes: Historical Background and Overview.- 1.1 Early Discoveries.- 1.2 Ingold's Breakthrough.- 1.3 Significance of the Spore Shape.- 1.4 Advances in Taxonomy.- 1.5 Substrata Colonized by Aquatic Hyphomycetes.- 1.6 Geographical Distribution and Temperature Preferences.- 1.7 Nutrition.- 1.8 Sporulation.- 1.9 Role in Food Webs.- 1.10 Water Chemistry.- References.- 2 Recent Developments in Stream Ecology and Their Relevance to Aquatic Mycology.- 2.1 Longitudinal Variation: Distinct Zones or Gradual Replacement?.- 2.2 The River Continuum Concept.- 2.3 Hyporheos and Groundwater.- 2.4 Pristine Rivers and Their Boundaries.- 2.5 The Effects of Altitude and Latitude.- 2.6 Drift and Compensatory Mechanisms.- 2.6.1 Transport Within and Between Streams.- 2.6.2 Exchanges with the Surrounding Terrestrial Habitats.- 2.6.3 Exchanges with the Sea.- 2.7 Conclusions.- References.- 3 Community Organization.- 3.1 Theories of Community Structure.- 3.1.1 Historical Background.- 3.1.2 Recent Criticisms.- 3.1.2.1 Physics as a Model for Ecology.- 3.1.2.2 Does Competition Explain Community Structure?.- 3.1.2.3 Predation and Disturbance.- 3.1.2.4 Deterministic Chaos.- 3.2 Fungal Ecology.- 3.2.1 Recent Developments.- 3.2.2 Aquatic Hyphomycetes.- 3.2.2.1 Relative Importance in Leaf Decay.- 3.2.2.2 Seasonal Occurrence.- 3.2.2.3 Competition.- 3.2.2.4 Niche Partitioning.- 3.2.2.5 Ephemeral and Divided Resources.- 3.3 Conclusions.- References.- 4 The Role of Woody Debris.- 4.1 Introduction.- 4.2 Occurrence of Aquatic Hyphomycetes on Wood.- 4.2.1 Sampling Techniques.- 4.2.2 Species Occurring on Wood.- 4.3 Role of Woody Debris in Aquatic Hyphomycete Life Cycles.- 4.3.1 Habitat and Nutritional Resource.- 4.3.2 Site of Sexual Reproduction.- 4.3.3 Site of Interspecific and Intraspecific Interactions.- 4.3.4 Reservoir.- 4.3.5 Long Distance Dispersal.- 4.4 Conclusions.- References.- 5 Anamorph-Teleomorph Relationships.- 5.1 Introduction.- 5.2 Techniques.- 5.3 Nomenclature.- 5.4 Synanamorphs.- 5.5 Entomophthorales with Branched Conidia.- 5.6 Ascomycete Teleomorphs.- 5.7 Basidiomycete Teleomorphs.- 5.8 Discussion.- References.- 6 Interactions with Invertebrates.- 6.1 Introduction.- 6.2 Effects of Fungi on Shredders.- 6.2.1 Shredder Preferences.- 6.2.2 Shredder Nutrition.- 6.2.2.1 Growth and Survivorship.- 6.2.2.2 Digestive Adaptations.- 6.2.2.3 Contribution of Fungi to Shredder Nutrition.- 6.3 Effects of Shredders on Fungi.- 6.4 Conclusions.- References.- 7 Attachment and Germination of Conidia.- 7.1 Introduction.- 7.2 Conidial Attachment.- 7.3 Germination.- 7.4 Mucilage Secretion.- 7.5 Appressorium Formation.- 7.6 Influence of Attachment Structures on the Strength of Adhesion.- 7.6.1 Tetraradiate Conidia.- 7.6.2 Sigmoid Conidia.- 7.6.3 Ovoid Conidia.- 7.7 Conclusions.- References.- 8 Water Chemistry.- 8.1 Introduction.- 8.2 Field Studies - Species Diversity and pH.- 8.3 Alkalinity and pH.- 8.3.1 Studies in Acidic Streams.- 8.3.2 Chemical Characteristics of Acid Waters.- 8.3.3 Elevated Aluminum (Ali) Levels in Acidic Streams and Reduced Microbial Metabolism on Litter.- 8.3.4 Studies in Circumneutral and Alkaline Streams.- 8.3.5 Laboratory Studies of pH Tolerances.- 8.3.6 Laboratory Studies of pH and Activity of Cell-Wall Degrading Enzymes.- 8.4 Nitrogen and Phosphorus.- 8.5 Species Composition and Water Chemistry.- 8.6 Further Research.- References.- 9 Human Interference.- 9.1 Introduction.- 9.2 Organic Pollution.- 9.3 Heavy Metals.- 9.4 Pesticides.- 9.5 Acid Precipitation.- References.- 10 Research on the Indian Subcontinent.- 10.1 Introduction.- 10.2 Distribution.- 10.3 Regional Differences.- 10.4 Substrata.- 10.5 Survival Outside Streams.- 10.6 Other Studies.- 10.7 Conclusions.- References.- 11 Conclusions and Outlook.- References.