Email updates

Keep up to date with the latest news and content from BMC Evolutionary Biology and BioMed Central.

Open Access Research article

Phylogeography of the Italian vairone (Telestes muticellus, Bonaparte 1837) inferred by microsatellite markers: evolutionary history of a freshwater fish species with a restricted and fragmented distribution

Flavio Marchetto12, Serena Zaccara1*, Frauke M Muenzel2 and Walter Salzburger2*

Author Affiliations

1 Department of Biotechnology and Molecular Sciences, University of Insubria, via Dunant 3, 21100 Varese, Italy

2 Zoological Institute, University of Basel, Vesalgasse 1, 4055 Basel, Switzerland

For all author emails, please log on.

BMC Evolutionary Biology 2010, 10:111  doi:10.1186/1471-2148-10-111

Published: 27 April 2010

Abstract

Background

Owing to its independence from the main Central European drainage systems, the Italian freshwater fauna is characterized by a high degree of endemicity. Three main ichthyogeographic districts have been proposed in Italy. Yet, the validity of these regions has not been confirmed by phylogenetic and population genetic analyses and a phylogeographic scenario for Italy's primary freshwater fish fauna is still lacking. Here, we investigate the phylogeography of the Italian vairone (Telestes muticellus).

Results

We sampled 38 populations representing the species' entire distribution range and covering all relevant drainage systems, and genotyped 509 individuals at eight variable microsatellite loci. Applying various population genetic analyses, we identify five distinct groups of populations that are only partly in agreement with the proposed ichthyogeographic districts. Our group I, which is formed by specimens from Veneto and the Po River system draining into the Adriatic Sea, corresponds to the Padano-Venetian ichthyogeographic district (PV), except for two Middle Adriatic drainages, which we identify as a separate group (III). The Tuscano-Latium district (TL) is equivalent to our group V. A more complex picture emerges for the Ligurian drainages: populations from Central Liguria belong to group I, while populations from West (group II) and East Liguria (group IV) form their own groups, albeit with affinities to PV and TL, respectively.

Conclusions

We propose a phylogeographic scenario for T. muticellus in which an initial T. muticellus stock became isolated from the 'Alpine' clade and survived the various glaciation cycles in several refugia. These were situated in the Upper Adriatic (groups I and II), the Middle Adriatic (group III), (East) Liguria (group IV) and Tuscano-Latium (group V). The population structure in the vairone is, in principal, in agreement with the two main ichthyogeographic districts (PV and TL), except for the two populations in the Middle Adriatic, which we identify as additional major "district".