Experimental Procedures
Samples
A total of 17 hybrid diploid (4) and triploid (13) specimens of S. alburnoides
were collected from the Tejo River Basin (Portugal), where all forms that
compose the complex are putatively present [7]. Five specimens of nuclear
‘‘nonhybrid’’ males of S. alburnoides and four of S. pyrenaicus (maternal ancestor
of the complex) were morphologically identified and collected to be
used as diploid controls of the A and P genomes. The determination of
genotype identity of individual samples was performed by a conjoined approach
of flow-cytometry measurements and the analysis of microsatellite
variation