Geographical genetic structuring and phenotypic variation in the Vellozia hirsuta (Velloziaceae) ochlospecies complex.
OBJECTIVE
Vellozia hirsuta forms a complex presenting wide morphological and anatomical variation, resulting in five specific names and 14 morpho-anatomical patterns occurring in disjunct populations. We carried out a phylogeographical study to investigate the existence of correlation among the genetic and morphological patterns within this complex, and to determine whether it is composed of various species or should be treated as an ochlospecies, a species having widely polymorphic and weakly polytypic complex variation, with morphological characteristics varying independently.


METHODS
We carried out phylogeographical analyses using cpDNA rpl32F-trnL intergenic region.


RESULTS
We found 20 haplotypes in 23 populations sampled. The populations are genetically structured (Φ(ST) = 0.818) into four phylogeographical groups demonstrating geographical structuring but with no correlation with morpho-anatomical patterns. Our analyses do not support recognizing any of the species now synonymized under Vellozia hirsuta. The northern populations were the most genetically differentiated and could be considered a distinct taxon, as they are also morphologically different.


CONCLUSIONS
It is recommended that Vellozia hirsuta be considered a single enormously variable species. The patterns of variation within V. hirsuta probably are related to climatic changes that occurred during the Pleistocene Epoch in tropical Brazil when reductions in forest cover favored the expansion of V. hirsuta populations into extensive lowland areas. The expansion of forest cover at the end of the glaciations would have again restricted the occurrence of campos rupestres vegetation to high elevations, which constitute the current centers of diversity of this species.
Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Belo Horizonte, Minas Gerais 31270-901 Brazil.
Ariane R
AR
Barbosa
Cecília F
CF
Fiorini
Viviane
V
Silva-Pereira
Renato
R
Mello-Silva
Eduardo L
EL
Borba
D001499:Bayes Theorem; D016000:Cluster Analysis; D018742:DNA, Chloroplast / Q000235:genetics; D021901:DNA, Intergenic / Q000235:genetics; D014644:Genetic Variation; D005828:Genetics, Population; D005843:Geography; D006239:Haplotypes / Q000235:genetics; D019684:Magnoliopsida / Q000033:anatomy & histology* / Q000235:genetics*; D010641:Phenotype; D010802:Phylogeny
D018742:DNA, Chloroplast; D021901:DNA, Intergenic