Aim The question whether free‐living protists are generally cosmopolitan is currently a matter of debate. In this study we investigate the geographical distribution of a distinctive testate amoeba species, Nebela ansata, and use our data to assess the potential for highly restricted distribution patterns in some protist species.
Methods We analysed (1) 3400 testate amoeba publications from North America and other continents, (2) unpublished slides of the Penard Collection of the Natural History Museum, London, UK, and (3) 104 Sphagnum samples from eastern North America. Non‐metric multidimensional scaling (NMDS) was used to visualize the similarities in testate amoeba community composition among 1012 North American samples, including two communities that contained N. ansata.
Results We rediscovered N. ansata at a site in New Jersey located close to its type locality, and in Nova Scotia. We also report the existence of an apparently unpublished museum specimen originally collected from New Jersey. Our extensive literature survey confirmed the presence of this species only in the temperate part of eastern North America. The NMDS revealed that communities with N. ansata were less similar to each other than to communities from other parts of North America, suggesting that favourable habitats for N. ansata occur in other Sphagnum‐dominated peatlands, a habitat type that has been extensively sampled in North America and elsewhere.
Main conclusions These data provide an unusually convincing case of a free‐living microorganism with a very limited distribution range in the temperate part of eastern North America. The remarkably restricted distribution of N. ansata highlights the extent of our ignorance about the natural history of free‐living microorganisms, and raises questions about the lack of attention to microbial diversity in conservation biology.
Document Type: Research Article
Affiliations: 1: Earth and Environmental Science Department, Lehigh University, Bethlehem, PA 18015, USA 2: Natural Science and Psychology, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK 3: Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, ON, Canada N2L 3G1 4: Department of Zoology and Ecology, Penza VG Belinsky State Pedagogical University, Lermontova str., 37, Penza 440026, Russia 5: Institute for Biology 2, RWTH Aachen University, D-52056 Aachen, Germany 6: Laboratory of Soil Biology, Institute of Biology, University of Neuchâtel, CH-2000 Neuchâtel, Switzerland
Publication date: 2011-10-01