ORIGINAL PAPER Mapping biodiversity hotspots and conservation priorities for the Euro-Mediterranean headwater ecosystems, as inferred from diversity and distribution of a water beetle lineage Marco Trizzino • Francesco Bisi • Luigi Maiorano • Adriano Martinoli • Marco Petitta • Damiano G. Preatoni • Paolo Audisio Received: 30 May 2014 / Revised: 25 August 2014 / Accepted: 10 September 2014 Ó Springer Science+Business Media Dordrecht 2014 Abstract Euro-Mediterranean running water ecosystems represent a highly threatened habitat due to draining, construction, agriculture, eutrophication, pollution and climate changes. Thereby, the associated biodiversity is often more threatened compared to any other ecosystem and the identification of biodiversity hotspots and conservation priorities for running water fauna is therefore a primary target. Here we focused on invertebrates, as important indicators of ecosystem functions, modelling a lineage of water beetles and investigating the conservation status of Euro-Mediterranean headwater ecosystems. We selected the ‘‘Haenydra’’ lineage (Hydraenidae, genus Hydraena) as representative taxon (92 species overall, known to occur from Iberian Peninsula to W Iran), analysing a geo- graphic database including literature, field-collecting and Museums data in order to map the distribution of biodiversity hotspots in Euro-Mediterranean headwater systems and locate the running water sites potentially important for invertebrates conservation. We Communicated by Dirk Sven Schmeller. Electronic supplementary material The online version of this article (doi:10.1007/s10531-014-0798-z) contains supplementary material, which is available to authorized users. M. Trizzino Istituto Oikos, Conservazione delle Risorse Naturali e Sviluppo Sostenibile, Via Crescenzago 1, 20134 Milan, Italy M. Trizzino (&) Á F. Bisi Á A. Martinoli Á D. G. Preatoni Dipartimento di Scienze Teoriche e Applicate, Universita ` dell’Insubria, Via H. Dunant, 3, 21100 Varese, Italy e-mail: marco.trizzino83@gmail.com L. Maiorano Á P. Audisio Dipartimento di Biologia e Biotecnologie ‘‘C. Darwin’’, Sapienza Universita ` degli Studi di Roma, Via A. Borelli, 50, 00161, 00185 Rome, Italy M. Petitta Dipartimento di Scienze della Terra, Sapienza Universita ` degli Studi di Roma, Piazzale A. Moro, 5, 00185 Rome, Italy 123 Biodivers Conserv DOI 10.1007/s10531-014-0798-z