Heterogeneous genetic structure in eastern North American peatmosses (Sphagnum)

<p><span><span><span>Bryophytes generally have broad geographic ranges that suggest high dispersal ability. The aim of this study was to test hypotheses about dispersal limitation, as indicated by isolation by distance (IBD), in four spore producing species of the moss genus <i>Sphagnum</i> (<i>S. carolinianum</i>, <i>S. missouricum</i>, <i>S. macrophyllum</i>, <i>S. pylaesii</i>), and to assess whether plants in the southern United States harbor high levels of unique alleles and/or other indicators of exceptional genetic diversity. IBD was detected in all four species, but regional patterns of genetic structure were very species-specific. One species, <i>S. macrophyllum</i>, exhibited differentiation between northern and southern genetic groups that appear to reflect more ancient phylogenetic diversification.</span></span></span></p>