Portal de Periódicos da CAPES

The Rutilus alburnoides complex (Cyprinidae): evidence for a hybrid origin

2009; Wiley; Volume: 35; Issue: 1 Linguagem: Inglês

10.1111/j.1439-0469.1997.tb00398.x

1439-0469

Maria Judite Alves, Maria M. Coelho, Maria João Collares‐Pereira,

Genetic diversity and population structure

A genetic survey of 18 presumptive enzyme loci was conducted on members of the diploid-triploid R. alburnoides complex in order to test the hypothesis of hybrid origin. Most specimens examined were heterozygous at a high proportion of loci, with seven loci showing virtually fixed heterozygosity in some or all populations. This observation strongly supports the hypothesized hybrid ancestry. Involvement in the origin of the R. alburnoides complex was examined by comparison of allels with those observed in the other diploid cyprinids that inhabit the same Portuguese drainages. Allelic composition at the homozygous loci IDDH* and LDH-B* seems to rule out the genus Chondrostoma and other members of the genus Rutilus as one of the ancestors, and supports Leuciscus sp. as one parental species involved in the putative hybrid origin of the R. alburnoides complex. Moreover, with few exceptions, all specimens exhibited at every locus one or two alleles also present in extant populations of Leuciscus. The indentity of the other parental taxon remains unclear. Five diploid males exhibited multilocus genotypes that fit to the hypothetical genotype(s) of the ‘missing’ ancestor. However, the possibility exists that a hybrid female could produce or re-create a genotype of a parental species.