Critically endangered species representing ancient, evolutionarily isolated lineages must be give... more Critically endangered species representing ancient, evolutionarily isolated lineages must be given priority when allocating resources for conservation projects. Sound phylogenetic analyses and divergence time estimations are required to detect them, and studies on their population genetics, ecological requirements and breeding system are needed to understand their evolutionary history and to design efficient conservation strategies. Here we present the paradigmatic case of Avellara, a critically endangered monotypic genus of Compositae inhabiting a few swamps in the W-SW Iberian coastal plains. Our phylogenetic and dating analyses based on nuclear (ITS) and plastid (matK) DNA sequences support a Miocene (>8.6 Ma) divergence between Avellara and closely related genera, resulting in a marked morphological and ecological differentiation. We found alarmingly low levels of genetic diversity, as based on AFLPs and plastid DNA sequences, and confirmed the prevalence of clonal reproduction. Species distribution modeling suggested a large macroclimatically suitable area for Avellara in W Iberian Peninsula, but its apparently narrow microecological requirements restrict its distribution to peatlands with low-mineralized waters. Although five populations have been recorded from Spain and Portugal in the past, its current distribution may be reduced to only one population recurrently found in the last decade,but threatened by herbivory and habitat degradation. All this agrees with the consideration of Avellara as a threatened species with a high phylogenetic singularity and makes it a flagship species for plant conservation in both Spain and Portugal, which should be given priority in the design of in situ and ex situ conservation programs. This article is protected by copyright. All rights reserved.
Interspecific gene flow is increasingly recognized as an important evolutionary phenomenon in pla... more Interspecific gene flow is increasingly recognized as an important evolutionary phenomenon in plants. A surprising observation is that historical introgression is often inferred between species that presently have geographic and reproductive barriers that would appear to prohibit the inferred sexual exchange. A striking example concerns Gossypium aridum (subsection Erioxylum); previous analyses have shown that populations from Colima (southwestern Mexico) have a chloroplast genome (cpDNA) similar to that of a different taxonomic subsection (Integrifolia) that presently is confined to Baja California and the Galapagos Islands, whereas other G. aridum populations share a cpDNA lineage with each other and with other species in subsection Erioxylum. To evaluate further the possibility that this cpDNA evidence reflects introgression as opposed to some other evolutionary process, as well as to explore patterns of genetic diversity and similarity in both subsections, we conducted amplified fragment-length polymorphism (AFLP) analysis using 50 populations representing all seven species in the two subsections. Genetic diversity is high in G. aridum, and is strongly correlated with geography, as are similarities among the five species in subsection Erioxylum. This subsection is genetically distant from the two species in subsection Integrifolia, whose populations are highly similar inter se. Populations of G. aridum from Colima are genetically distinct from the remainder of the species, and exhibit a comparatively high frequency of AFLP fragments that otherwise are diagnostic of the Integrifolia lineage. These data implicate intersubsectional introgression between presently allopatric and genetically isolated clades, giving rise to a morphologically cryptic, introgressant entity. Biogeographic considerations suggest that this history was initiated following migration of one or more seeds from Baja California to the Colima coast, perhaps during the Pleistocene. We suggest that cryptic and seemingly improbable interspecific introgression and molecular differentiation may be more common than appreciated in angiosperm evolution.
... 30TVL20 VL2902, «Colmenar Viejo: inter oppida Colmenar Viejo et Hoyo de Manzanares, 900 m. In... more ... 30TVL20 VL2902, «Colmenar Viejo: inter oppida Colmenar Viejo et Hoyo de Manzanares, 900 m. In ... MA RIVAS PONCE, C. SORIANO MARTÍN & FJ FERNÁNDEZ CASAS (1985: 130 ... 800 m. Praditos sobre berrocal; substrato silíceo», J. J. González Aguilera & A. Susanna de la ...
The complexity of the evolutionary history of Senecio is reflected in its conflicted taxonomy. Wi... more The complexity of the evolutionary history of Senecio is reflected in its conflicted taxonomy. Within this genus, Senecio section Crociseris (Compositae, Senecioneae), a group of perennial herbs distributed in Europe, western and Central Asia, and northwestern Africa, was not fully revised. A worldwide revision of this section recognizing 28 species and eight subspecies is presented here. The main morphological characters revealed as useful for distinguishing between species are the number and shape of supplementary and involucral bracts, synflorescence architecture, indumentum, and the shape and size of leaves and achenes. In this new taxonomic treatment S. provincialis and S. lagascanus have been segregated from S. doronicum, within which three subspecies are recognized (S. doronicum subsp. orientalis is validly published herein). On the other hand, S. ruthenensis from France and S. lusitanicus from Portugal have been synonymized to S. lagascanus, as well as S. ovatifolius, S. pis...
• Nuclear microsatellite primers were developed for the weedy herb Anacyclus clavatus to study th... more • Nuclear microsatellite primers were developed for the weedy herb Anacyclus clavatus to study the genetic structure of hybrid zones with closely related taxa in the western Mediterranean Basin, where different floral phenotypes are present. • We obtained two microsatellite libraries using next-generation sequencing and Sanger sequencing of cloned restriction fragments. A total of 13 polymorphic and 11 monomorphic loci were identified in three Iberian populations of A. clavatus. The primers amplified di- and trinucleotide repeats with 1-8 alleles per locus. Most primers also amplified in A. homogamos, A. monanthos, A. radiatus, and A. valentinus. • These results indicate the utility of these markers in A. clavatus for population genetic and hybridization studies as well as their applicability across the genus.
The present study provides results of multi-species coalescent species tree analyses of DNA seque... more The present study provides results of multi-species coalescent species tree analyses of DNA sequences sampled from multiple nuclear and plastid regions to infer the phylogenetic relationships among the members of the subtribe Leucanthemopsidinae (Compositae, Anthemideae), to which besides the annual Castrilanthemum debeauxii (Degen, Hervier & É.Rev.) Vogt & Oberp., one of the rarest flowering plant species of the Iberian Peninsula, two other unispecific genera (Hymenostemma, Prolongoa), and the polyploidy complex of the genus Leucanthemopsis belong. Based on sequence information from two single- to low-copy nuclear regions (C16, D35, characterised by Chapman et al. (2007)), the multi-copy region of the nrDNA internal transcribed spacer regions ITS1 and ITS2, and two intergenic spacer regions of the cpDNA gene trees were reconstructed using Bayesian inference methods. For the reconstruction of a multi-locus species tree we applied three different methods: (a) analysis of concatenated...
Critically endangered species representing ancient, evolutionarily isolated lineages must be give... more Critically endangered species representing ancient, evolutionarily isolated lineages must be given priority when allocating resources for conservation projects. Sound phylogenetic analyses and divergence time estimations are required to detect them, and studies on their population genetics, ecological requirements and breeding system are needed to understand their evolutionary history and to design efficient conservation strategies. Here we present the paradigmatic case of Avellara, a critically endangered monotypic genus of Compositae inhabiting a few swamps in the W-SW Iberian coastal plains. Our phylogenetic and dating analyses based on nuclear (ITS) and plastid (matK) DNA sequences support a Miocene (>8.6 Ma) divergence between Avellara and closely related genera, resulting in a marked morphological and ecological differentiation. We found alarmingly low levels of genetic diversity, as based on AFLPs and plastid DNA sequences, and confirmed the prevalence of clonal reproduction. Species distribution modeling suggested a large macroclimatically suitable area for Avellara in W Iberian Peninsula, but its apparently narrow microecological requirements restrict its distribution to peatlands with low-mineralized waters. Although five populations have been recorded from Spain and Portugal in the past, its current distribution may be reduced to only one population recurrently found in the last decade,but threatened by herbivory and habitat degradation. All this agrees with the consideration of Avellara as a threatened species with a high phylogenetic singularity and makes it a flagship species for plant conservation in both Spain and Portugal, which should be given priority in the design of in situ and ex situ conservation programs. This article is protected by copyright. All rights reserved.
Interspecific gene flow is increasingly recognized as an important evolutionary phenomenon in pla... more Interspecific gene flow is increasingly recognized as an important evolutionary phenomenon in plants. A surprising observation is that historical introgression is often inferred between species that presently have geographic and reproductive barriers that would appear to prohibit the inferred sexual exchange. A striking example concerns Gossypium aridum (subsection Erioxylum); previous analyses have shown that populations from Colima (southwestern Mexico) have a chloroplast genome (cpDNA) similar to that of a different taxonomic subsection (Integrifolia) that presently is confined to Baja California and the Galapagos Islands, whereas other G. aridum populations share a cpDNA lineage with each other and with other species in subsection Erioxylum. To evaluate further the possibility that this cpDNA evidence reflects introgression as opposed to some other evolutionary process, as well as to explore patterns of genetic diversity and similarity in both subsections, we conducted amplified fragment-length polymorphism (AFLP) analysis using 50 populations representing all seven species in the two subsections. Genetic diversity is high in G. aridum, and is strongly correlated with geography, as are similarities among the five species in subsection Erioxylum. This subsection is genetically distant from the two species in subsection Integrifolia, whose populations are highly similar inter se. Populations of G. aridum from Colima are genetically distinct from the remainder of the species, and exhibit a comparatively high frequency of AFLP fragments that otherwise are diagnostic of the Integrifolia lineage. These data implicate intersubsectional introgression between presently allopatric and genetically isolated clades, giving rise to a morphologically cryptic, introgressant entity. Biogeographic considerations suggest that this history was initiated following migration of one or more seeds from Baja California to the Colima coast, perhaps during the Pleistocene. We suggest that cryptic and seemingly improbable interspecific introgression and molecular differentiation may be more common than appreciated in angiosperm evolution.
... 30TVL20 VL2902, «Colmenar Viejo: inter oppida Colmenar Viejo et Hoyo de Manzanares, 900 m. In... more ... 30TVL20 VL2902, «Colmenar Viejo: inter oppida Colmenar Viejo et Hoyo de Manzanares, 900 m. In ... MA RIVAS PONCE, C. SORIANO MARTÍN & FJ FERNÁNDEZ CASAS (1985: 130 ... 800 m. Praditos sobre berrocal; substrato silíceo», J. J. González Aguilera & A. Susanna de la ...
The complexity of the evolutionary history of Senecio is reflected in its conflicted taxonomy. Wi... more The complexity of the evolutionary history of Senecio is reflected in its conflicted taxonomy. Within this genus, Senecio section Crociseris (Compositae, Senecioneae), a group of perennial herbs distributed in Europe, western and Central Asia, and northwestern Africa, was not fully revised. A worldwide revision of this section recognizing 28 species and eight subspecies is presented here. The main morphological characters revealed as useful for distinguishing between species are the number and shape of supplementary and involucral bracts, synflorescence architecture, indumentum, and the shape and size of leaves and achenes. In this new taxonomic treatment S. provincialis and S. lagascanus have been segregated from S. doronicum, within which three subspecies are recognized (S. doronicum subsp. orientalis is validly published herein). On the other hand, S. ruthenensis from France and S. lusitanicus from Portugal have been synonymized to S. lagascanus, as well as S. ovatifolius, S. pis...
• Nuclear microsatellite primers were developed for the weedy herb Anacyclus clavatus to study th... more • Nuclear microsatellite primers were developed for the weedy herb Anacyclus clavatus to study the genetic structure of hybrid zones with closely related taxa in the western Mediterranean Basin, where different floral phenotypes are present. • We obtained two microsatellite libraries using next-generation sequencing and Sanger sequencing of cloned restriction fragments. A total of 13 polymorphic and 11 monomorphic loci were identified in three Iberian populations of A. clavatus. The primers amplified di- and trinucleotide repeats with 1-8 alleles per locus. Most primers also amplified in A. homogamos, A. monanthos, A. radiatus, and A. valentinus. • These results indicate the utility of these markers in A. clavatus for population genetic and hybridization studies as well as their applicability across the genus.
The present study provides results of multi-species coalescent species tree analyses of DNA seque... more The present study provides results of multi-species coalescent species tree analyses of DNA sequences sampled from multiple nuclear and plastid regions to infer the phylogenetic relationships among the members of the subtribe Leucanthemopsidinae (Compositae, Anthemideae), to which besides the annual Castrilanthemum debeauxii (Degen, Hervier & É.Rev.) Vogt & Oberp., one of the rarest flowering plant species of the Iberian Peninsula, two other unispecific genera (Hymenostemma, Prolongoa), and the polyploidy complex of the genus Leucanthemopsis belong. Based on sequence information from two single- to low-copy nuclear regions (C16, D35, characterised by Chapman et al. (2007)), the multi-copy region of the nrDNA internal transcribed spacer regions ITS1 and ITS2, and two intergenic spacer regions of the cpDNA gene trees were reconstructed using Bayesian inference methods. For the reconstruction of a multi-locus species tree we applied three different methods: (a) analysis of concatenated...
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