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Global diversity of inland water cnidarians

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Global diversity of inland water cnidarians is low, containing <40 species belonging to phylogenetically distinct groups representing independent invasion events: the common and cosmopolitan hydras (12–15 species); the sporadically occurring freshwater medusae (6–16 sp.); the Cordylophorinae (2 sp.); the parasitic Polypodium (1 sp.); the medusae occurring in saline lakes (4 sp.). Freshwater cnidarians inhabit nearly all types of freshwater on all continents (except Antarctica), but only a few species have cosmopolitan distributions. Due to uncertainty in species knowledge, fine scale regions of endemicity are not yet clear.

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This work was partly funded by the Swiss Federal Office of Education and Science within the framework of the European Union Environment and Climate projects CLIME (EVK1-CT-2002-00121) and Eurolimpacs (GOCE-CT-2003-505540).

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Correspondence to Thomas Jankowski.

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Guest editors: E. V. Balian, C. Lévêque, H. Segers & K. Martens

Freshwater Animal Diversity Assessment

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Jankowski, T., Collins, A.G. & Campbell, R. Global diversity of inland water cnidarians. Hydrobiologia 595, 35–40 (2008).

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