Chloroplast DNA sequences were obtained from 331 Asplenium ceterach plants representing 143 populations from throughout the range of the complex in Europe, plus outlying sites in North Africa and the near East. We identified nine distinct haplotypes from a 900 bp fragment of trnL-trnF gene. Tetraploid populations were encountered throughout Europe and further afield, whereas diploid populations were scarcer and predominated in the Pannonian-Balkan region. Hexaploids were encountered only in southern Mediterranean populations. Four haplotypes were found among diploid populations of the Pannonian-Balkans indicating that this region formed a northern Pleistocene refugium. A separate polyploid complex centred on Greece, comprises diploid, tetraploid and hexaploid populations with two endemic haplotypes and suggests long-term persistence of populations in the southern Mediterranean. Three chloroplast DNA (cpDNA) haplotypes were common among tetraploids in Spain and Italy, with diversity reducing northwards suggesting expansion from the south after the Pleistocene. Our cpDNA and ploidy data indicate at least six independent origins of polyploids.

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Isolated oceanic archipelagos are natural laboratories of evolution, ideally suited for in situ studies of speciation processes, and the recent availability of checklist data for many archipelagos worldwide (e.g. Izquierdo et al., 2004;

Little is known about the mode of transmission of chloroplasts in ferns, despite the importance of such knowledge for molecular phylogenetic and biosystematic studies. Andersson‐Kötto (1930, 1931) inferred from crossing experiments that chloroplasts are inherited biparentally in Asplenium scolopendrium L. Here we present evidence from artificial hybridisation that demonstrates maternal inheritance of chloroplast DNA in the genus Asplenium (Aspleniaceae, Pteridophyta) using length variation in a non‐coding spacer (trnLUAA‐trnFGAA) in the chloroplast DNA.

Macaronesia, which includes five mid-Atlantic archipelagos (Azores, Madeira, Selvagems, Canaries, and Cape Verdes), has been traditionally recognized as a distinct biogeographic unit whose circumscription has been intimately associated with the hypothesis that the flora is a relict of a formerly broadly distributed subtropical Tertiary flora. The concept of Macaronesia is revisited here using parsimony and Bayesian analyses of floristic data sets for the moss, liverwort, and pteridophyte floras. All analyses reject the monophyly of Macaronesia s.l., resolving the Cape Verdes with tropical Africa. Of the other Macaronesian archipelagos, the liverwort and pteridophyte analyses support, or could not reject, an Azorean-Madeiran-Canarian clade (hereafter Macaronesia s.s.), but the moss analysis resolves the Canary Islands as sister to North Africa, thus rejecting the concept of Macaronesia s.s. for this group. Dynamic interchange of taxa with neighboring continental areas rather than relictualism best explains the relationships of the Cape Verde cryptogamic flora and the Canary Island moss flora. In contrast, relictualism is consistent with a monophyletic Macaronesia s.s. for liverworts and pteridophytes. However, from the limited information available on relationships of endemic cryptogams, this explanation alone may be unsatisfactory. Spatially congruent patterns may, in fact, conceal a complex mixture of relictual distributions and more recent speciation and dispersal events.