Local versus global diversity of microorganisms: Cryptic diversity of ciliated protozoa

Authors: Fenchel, T., Esteban, G.F. and Finlay, B.J.

Journal: Oikos

Volume: 80

Issue: 2

Pages: 220-225

ISSN: 0030-1299

DOI: 10.2307/3546589

Abstract:

Microbial species diversity, both global and local, is still poorly understood. In this study all species of ciliated protozoa were recorded microscopically from ~1 cm2 sediment collected from a small lake and from a marine shallow-water bay. Additional adjacent sediment samples (together representing <50 cm2) were then incubated under a variety of culture conditions to reveal 'cryptic species' that are present as resting cysts or are too rare to be found microscopically. About 85 and 57% of the total number of observed species from the limnic and marine sediment, respectively, were such cryptic species. In both cases the number of species found in <50 cm2 of sediment represented about 75% of all ciliate species ever recorded from these two previously well-studied habitats, and about 8% of all named free-living ciliates. These observations support the assumption that in the case of microorganisms 'everything is everywhere' and that their global species diversity is relatively limited.

Source: Scopus