Learn More
Most of the small ciliate protozoa, including Dasytricha ruminantium and Entodinium spp. living in the rumen of sheep, were found to have intracellular bacteria. These bacteria were not present in digestive vacuoles. They showed characteristic coenzyme F420 autofluorescence and they were detected with a rhodamine-labelled Archaea-specific oligonucleotide(More)
Psilotricha acuminata was described by Stein in 1859 as the type species of the ciliate genus Psilotricha Stein, 1859. The ciliate has rarely been found since, and its infraciliature has never been described with the aid of silver-impregnation techniques. We have found P. acuminata Stein, 1859 in soil samples from upland grassland in Scotland (U.K.). Living(More)
Free-living microbes are by far the most abundant group of organisms in the biosphere, yet estimates of global species richness remain nebulous, and there is no consensus regarding the likely geographical distribution of species. Both uncertainties are addressed by the suggestion that the vast abundance of microbes may drive their ubiquitous random(More)
Microbial eukaryotes that are morphologically indistinguishable (i.e. 'morphospecies') tend to be genetically diverse. While most protist morphospecies have cosmopolitan distribution, it has been suggested that ribotypes (unique rRNA gene sequences) or rRNA sequence clusters do have biogeography and such clusters may correlate with particular(More)
Ubiquitous dispersal of free-living microbial species implies that each and every ecosystem supports a 'seedbank' of microbial species that are imported by random dispersal. However, many of the microbial species present in any particular ecosystem will probably never thrive there because the local environment is unsuitable for their population growth. To(More)
We have developed a method for determining the potential abundance of free-living protozoa in soil. The method permits enumeration of four major functional groups (flagellates, naked amoebae, testate amoebae, and ciliates) and it overcomes some limitations and problems of the usual 'direct' and 'most probable number' methods. Potential abundance is(More)
Towards the end of the 17th century, Leeuwenhoek built "magnifying glasses" that enabled him to see and describe protozoa for the first time. Continued exploration of the natural history of protozoa during the past 300 years has progressed far beyond simply documenting morphospecies (global total probably <20,000). We now realize that protozoan(More)
We report aerobic eukaryotic microbial life in the dimly lit anoxic water layer of a small freshwater lake. The microbial eukaryote is the ciliated protozoon Histiobalantium natans. Electron microscopy of thin sections shows that the cytoplasm of the ciliate harbours sequestered chloroplasts and sequestered mitochondria. The sequestered chloroplasts are(More)