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Modesto Luceno - One of the best experts on this subject based on the ideXlab platform.
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geographical speciation related to pleistocene range shifts in the western mediterranean mountains reseda sect glaucoreseda Resedaceae
Taxon, 2010Co-Authors: Santiago Martinbravo, Virginia Valcarcel, Pablo Vargas, Modesto LucenoAbstract:Reseda sect. Claucoreseda is a monophyletic group composed of five endemic tetraploid species with a disjunct distribution in the high mountains and plateaus of the Iberian Peninsula and Morocco. It was previously suggested that range shifts induced by Quaternary glaciations played an important role in the speciation of the group. We studied the evolution of R. sect. Glaucoreseda in order to infer historical range dynamics and speciation processes, and to understand current distributional patterns. Phylogeographic analyses were performed using nuclear ribosomal ITS and plastid trnL-F and rps16 sequences. Cloning of additive ITS sequences was carried out to elucidate the origin of intra-individual polymorphisms. A dated phylogeny based on ITS and cpDNA (rbcL, matK, trnL-F) sequences was used to estimate divergence times of R. sect. Glaucoreseda. Time estimates using Penalized Likelihood analyses indicate a late Pleistocene diversification of R. sect. Glaucoreseda. Incomplete lineage sorting of ancestral polymorphisms due to recent divergence, rather than rampant hybridisation, is suggested as the main cause of the phylogenetic incongruence detected between nuclear and plastid datasets. Our results support the vicariance hypothesis for population disjunctions in the Iberian Peninsula, in which an ancestral, widespread species could have undergone differentiation by Quaternary interglacial fragmentation. In contrast, long-distance dispersal across the Strait of Gibraltar may have been involved in the colonisation of North African plateaus by R. battandieri.
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is oligomeris Resedaceae indigenous to north america molecular evidence for a natural colonization from the old world
American Journal of Botany, 2009Co-Authors: Santiago Martinbravo, Pablo Vargas, Modesto LucenoAbstract:Oligomeris linifolia constitutes one of the few examples of intercontinental disjunctions at the species level between the arid regions of the Old World and SW North America. The status of the American populations has been obscure, with some authors considering the populations to be introduced, whereas others believe them to be native. To clarify these confl icting opinions, we performed phylogeographic analyses using nuclear ribosomal ITS and plastid trnL-F and rps16 sequences to infer the origin of the disjunct American populations. Two independent molecular clock approaches based on ITS and cpDNA sequences ( rbcL , matK , trnL-F ) were used to estimate a divergence time of O. linifolia . Low levels of sequence divergence and estimates of relatively recent splits of Oligomeris lineages disagree with the vicariance hypotheses traditionally suggested to account for New – Old World disjunctions. In addition, signifi cant genetic differentiation of American populations does not indicate a recent anthropogenic introduction. Morphological uniformity and the sharing of haplotypes between disjunct populations, together with the molecular clock results, suggest that a long-distance dispersal event from the Old Word to SW North America may have taken place during the Quaternary, in spite of limited dispersal mechanisms in Oligomeris .
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molecular systematics and biogeography of Resedaceae based on its and trnl f sequences
Molecular Phylogenetics and Evolution, 2007Co-Authors: Santiago Martinbravo, Harald Meimberg, Modesto Luceno, Wolfgang Markl, Virginia Valcarcel, Christian Brauchler, Pablo Vargas, Gunther HeublAbstract:Abstract The Resedaceae, containing 6 genera and ca. 85 species, are widely distributed in the Old World, with a major center of species diversity in the Mediterranean basin. Phylogenetic analyses of ITS and plastid trnL–trnF sequences of 66 species from all genera of the Resedaceae reveal (1) monophyly of the family, in congruence with preliminary phylogenetic studies; (2) molecular support for the traditional morphological subdivision of the Resedaceae into three tribes according to ovary and placentation types, and carpel number; (3) two monophyletic genera (Caylusea, Sesamoides), and one natural group (core Reseda), which includes the remaining four genera of the family (Ochradenus, Oligomeris, Randonia, Reseda); (4) a monophyletic origin for four of the six taxonomic sections recognized within Reseda (Leucoreseda, Luteola, Glaucoreseda, Phyteuma). Our results lead us to interpret an increment of the basic chromosome number in the family from x = 5 to x = 6 in at least two independent instances, and a broad representation of polyploids in multiple lineages across phylogenies, including association between octoploids and alien invasion in many parts of the world. Species diversity, endemism number, phylogenetic relationships and sequence divergence in Resedaceae suggest two major centers of differentiation, one in the western Mediterranean, and the other in the eastern Mediterranean and SW Asia. Two independent colonization events to the Canary Islands from Africa are indicated for the two Canarian Reseda endemics.
Santiago Martinbravo - One of the best experts on this subject based on the ideXlab platform.
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rediscovery of the restricted endemic reseda balansae Resedaceae in turkey
Phytotaxa, 2018Co-Authors: Emre Cilden, şinasi Yildirimli, Golshan Zare, Santiago MartinbravoAbstract:Reseda balansae Mull. Arg. (Resedaceae) is a very restricted and endangered Turkish endemic species known only from Mersin province (South Turkey), in a hotspot of biodiversity. It was first collected in 1855, and subsequently described in 1857. Afterwards, it was only collected once again in 1896. In this study we report the rediscovery of these two populations of R. balansae in Turkey more than 120 years after its last known collection. We provide a detailed revised description of this poorly known species and comments about its taxonomy (including designation of a lectotype), distribution and ecology. We also perform the first conservation assessment of the species at a global scale under IUCN categories and criteria, resulting in the proposal of the critically endangered category for the species, which apparently persists in one single population, since the type population has recently been destroyed.
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reseda minoica Resedaceae a new species from the eastern mediterranean region
Annales Botanici Fennici, 2013Co-Authors: Santiago Martinbravo, Pedro JimenezmejiasAbstract:Reseda minoica Martin-Bravo & Jim. Mejias (Resedaceae), a new species from the eastern Mediterranean region, is described and illustrated. It is distributed in Crete (Gavdos Island), Cyprus and S Anatolia (Mersin), where it grows mostly on basic, occasionally schistose, substrates near the coast. It is included in Reseda sect. Phyteuma, a taxonomically complex group mostly containing narrow endemics from the western or eastern Mediterranean region. Reseda minoica has been confused with R. odorata, R. orientalis and R. balansae in Crete, Cyprus and Turkey. It can be distinguished from those by the lower number of stamens, seed size, colour of petals and indumentum. An identification key to the eastern Mediterranean taxa of Reseda sect. Phyteuma is provided.
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biogeography of flowering plants a case study in mignonettes Resedaceae and sedges carex cyperaceae
2012Co-Authors: Santiago Martinbravo, Marcial EscuderoAbstract:Biogeography is a multidisciplinary science that studies the past and present geographic distribution of organisms and the causes behind it. The combination of historical events and evolutionary processes has usually an outstanding role when explaining the shape of a species range. As already noted by Darwin more than 150 years ago, patterns of species distribution may often be seen as clear footsteps of their evolution and diversification (Darwin, 1859). It is now also well known that geological events (i.e. continental drift, orogeny or island formation) and climatic oscillations occurred during the recent geological history of the Earth, like the cooling and aridification that took place during the Pliocene (5.3 – 2.5 million years ago, m.a) and the Pleistocene glaciations (1.8 – 0.01 m.a), prompted great range shifts. These geological and/or climatic changes caused, in some cases, the extinction of species; in many others, they provided conditions of reproductive isolation and/or genetic divergence between populations and, eventually, produced speciation, the engine of biodiversity.
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geographical speciation related to pleistocene range shifts in the western mediterranean mountains reseda sect glaucoreseda Resedaceae
Taxon, 2010Co-Authors: Santiago Martinbravo, Virginia Valcarcel, Pablo Vargas, Modesto LucenoAbstract:Reseda sect. Claucoreseda is a monophyletic group composed of five endemic tetraploid species with a disjunct distribution in the high mountains and plateaus of the Iberian Peninsula and Morocco. It was previously suggested that range shifts induced by Quaternary glaciations played an important role in the speciation of the group. We studied the evolution of R. sect. Glaucoreseda in order to infer historical range dynamics and speciation processes, and to understand current distributional patterns. Phylogeographic analyses were performed using nuclear ribosomal ITS and plastid trnL-F and rps16 sequences. Cloning of additive ITS sequences was carried out to elucidate the origin of intra-individual polymorphisms. A dated phylogeny based on ITS and cpDNA (rbcL, matK, trnL-F) sequences was used to estimate divergence times of R. sect. Glaucoreseda. Time estimates using Penalized Likelihood analyses indicate a late Pleistocene diversification of R. sect. Glaucoreseda. Incomplete lineage sorting of ancestral polymorphisms due to recent divergence, rather than rampant hybridisation, is suggested as the main cause of the phylogenetic incongruence detected between nuclear and plastid datasets. Our results support the vicariance hypothesis for population disjunctions in the Iberian Peninsula, in which an ancestral, widespread species could have undergone differentiation by Quaternary interglacial fragmentation. In contrast, long-distance dispersal across the Strait of Gibraltar may have been involved in the colonisation of North African plateaus by R. battandieri.
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molecular data helps traditional taxonomy re evaluation of reseda collina Resedaceae and a new record for europe
Folia Geobotanica, 2009Co-Authors: Santiago Martinbravo, Pedro JimenezmejiasAbstract:Reseda collina is included in Reseda section Phyteuma, a monophyletic and morphologically well-defined group that is also characterized by taxonomic problems regarding species circumscription. The status of this species has been controversial, usually being subordinated to the widespread R. phyteuma. A study of R. collina and allied taxa based on morphological and molecular (nuclear ITS, plastid trnL-F) data supports the taxonomic identity of R. collina and its separation from R. phyteuma. An epitype is designated to support the holotype and prevent future nomenclature problems. In addition, our molecular and morphological analyses suggest that some problematic southeastern Iberian populations, previously identified as R. phyteuma, belong to R. collina, which implies a new European record for this species that was previously considered as a northwestern African endemic. Following this finding, biogeographic relationships between the southern Iberian Peninsula and northwestern Africa are also discussed.
Niels Agerbirk - One of the best experts on this subject based on the ideXlab platform.
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glucosinolate profiles and phylogeny in barbarea compared to other tribe cardamineae brassicaceae and reseda Resedaceae based on a library of ion trap hplc ms ms data of reference desulfoglucosinolates
Phytochemistry, 2021Co-Authors: Niels Agerbirk, Cecilie Cetti Hansen, Carl Erik Olsen, Christiane Kiefer, Thure P Hauser, Stina Christensen, Karen R Jensen, Marian Orgaard, David I Pattison, Conny Bruun Asmussen LangeAbstract:A library of ion trap MS2 spectra and HPLC retention times reported here allowed distinction in plants of at least 70 known glucosinolates (GSLs) and some additional proposed GSLs. We determined GSL profiles of selected members of the tribe Cardamineae (Brassicaceae) as well as Reseda (Resedaceae) used as outgroup in evolutionary studies. We included several accessions of each species and a range of organs, and paid attention to minor peaks and GSLs not detected. In this way, we obtained GSL profiles of Barbarea australis, Barbarea grayi, Planodes virginica selected for its apparent intermediacy between Barbarea and the remaining tribe and family, and Rorippa sylvestris and Nasturtium officinale, for which the presence of acyl derivatives of GSLs was previously untested. We also screened Armoracia rusticana, with a remarkably diverse GSL profile, the emerging model species Cardamine hirsuta, for which we discovered a GSL polymorphism, and Reseda luteola and Reseda odorata. The potential for aliphatic GSL biosynthesis in Barbarea vulgaris was of interest, and we subjected P-type and G-type B. vulgaris to several induction regimes in an attempt to induce aliphatic GSL. However, aliphatic GSLs were not detected in any of the B. vulgaris types. We characterized the investigated chemotypes phylogenetically, based on nuclear rDNA internal transcribed spacer (ITS) sequences, in order to understand their relation to the species B. vulgaris in general, and found them to be representative of the species as it occurs in Europe, as far as documented in available ITS-sequence repositories. In short, we provide GSL profiles of a wide variety of tribe Cardamineae plants and conclude aliphatic GSLs to be absent or below our limit of detection in two major evolutionary lines of B. vulgaris. Concerning analytical chemistry, we conclude that availability of authentic reference compounds or reference materials is critical for reliable GSL analysis and characterize two publicly available reference materials: seeds of P. virginica and N. officinale.
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Comparison of glucosinolate diversity in the crucifer tribe Cardamineae and the remaining order Brassicales highlights repetitive evolutionary loss and gain of biosynthetic steps.
Phytochemistry, 2021Co-Authors: Niels Agerbirk, Cecilie Cetti Hansen, Christiane Kiefer, Thure P Hauser, Marian Orgaard, Conny Bruun Asmussen Lange, Don Cipollini, Marcus A KochAbstract:We review glucosinolate (GSL) diversity and analyze phylogeny in the crucifer tribe Cardamineae as well as selected species from Brassicaceae (tribe Brassiceae) and Resedaceae. Some GSLs occur widely, while there is a scattered distribution of many less common GSLs, tentatively sorted into three classes: ancient, intermediate and more recently evolved. The number of conclusively identified GSLs in the tribe (53 GSLs) constitute 60% of all GSLs known with certainty from any plant (89 GSLs) and apparently unique GSLs in the tribe constitute 10 of those GSLs conclusively identified (19%). Intraspecific, qualitative GSL polymorphism is known from at least four species in the tribe. The most ancient GSL biosynthesis in Brassicales probably involved biosynthesis from Phe, Val, Leu, Ile and possibly Trp, and hydroxylation at the β-position. From a broad comparison of families in Brassicales and tribes in Brassicaceae, we estimate that a common ancestor of the tribe Cardamineae and the family Brassicaceae exhibited GSL biosynthesis from Phe, Val, Ile, Leu, possibly Tyr, Trp and homoPhe (ancient GSLs), as well as homologs of Met and possibly homoIle (intermediate age GSLs). From the comparison of phylogeny and GSL diversity, we also suggest that hydroxylation and subsequent methylation of indole GSLs and usual modifications of Met-derived GSLs (formation of sulfinyls, sulfonyls and alkenyls) occur due to conserved biochemical mechanisms and was present in a common ancestor of the family. Apparent loss of homologs of Met as biosynthetic precursors was deduced in the entire genus Barbarea and was frequent in Cardamine (e.g. C. pratensis, C. diphylla, C. concatenata, possibly C. amara). The loss was often associated with appearance of significant levels of unique or rare GSLs as well as recapitulation of ancient types of GSLs. Biosynthetic traits interpreted as de novo evolution included hydroxylation at rare positions, acylation at the thioglucose and use of dihomoIle and possibly homoIle as biosynthetic precursors. Biochemical aspects of the deduced evolution are discussed and testable hypotheses proposed. Biosyntheses from Val, Leu, Ile, Phe, Trp, homoPhe and homologs of Met are increasingly well understood, while GSL biosynthesis from mono- and dihomoIle is poorly understood. Overall, interpretation of known diversity suggests that evolution of GSL biosynthesis often seems to recapitulate ancient biosynthesis. In contrast, unprecedented GSL biosynthetic innovation seems to be rare.
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Glucosinolate turnover in Brassicales species to an oxazolidin-2-one, formed via the 2-thione and without formation of thioamide
Phytochemistry, 2018Co-Authors: Niels Agerbirk, Annemarie Matthes, Pernille Ø. Erthmann, Luisa Ugolini, Susanna Cinti, Eleni Lazaridi, Jean-marc Nuzillard, Caroline Muller, Søren Bak, Patrick RollinAbstract:Glucosinolates are found in plants of the order Brassicales and hydrolyzed to different breakdown products, particularly after tissue damage. In Barbarea vulgaris R.Br. (Brassicaceae), the dominant glucosinolate in the investigated “G-type” is glucobarbarin, (S)-2-hydroxy-2-phenylethylglucosinolate. Formation of the nitrile from glucobarbarin was observed in vitro, while a previously suggested thioamide (synonym thionamide) was not confirmed. Resedine (5-phenyl-1,3-oxazolidin-2-one) was detected after glucobarbarin hydrolysis in crushed B. vulgaris leaves and siliques, but not in intact parts. The abundance increased for several hours after completion of hydrolysis. The corresponding 1,3-oxazolidine-2-thione (OAT), with the common name barbarin, was also formed, and appeared to be the precursor of resedine. Addition of each of two non-endogenous OATs, (S)-5-ethyl-5-methylOAT and (R)-5-vinylOAT (R-goitrin), to a leaf homogenate resulted in formation of the corresponding 1,3-oxazolidin-2-ones (OAOs), confirming the metabolic connection of OAT to OAO. Formation of OAOs was inhibited by prior brief heating of the homogenate, suggesting enzyme involvement. We suggest the conversion of OATs to OAOs to be catalyzed by an enzyme (“oxazolidinethionase”) responsible for turnover of OAT formed in intact plants. Resedine had been reported as an alkaloid from another species - Reseda luteola L. (Resedaceae) - naturally containing the glucosinolate glucobarbarin. However, resedine was not detected in intact R. luteola plants, but formed after tissue damage. The formation of resedine in two families suggests a broad distribution of putative OATases in the Brassicales; potentially involved in glucosinolate turnover that needs myrosinase activity as the committed step. In agreement with the proposed function of OATase, several candidate genes for myrosinases in glucosinolate turnover in intact plants were discovered in the B. vulgaris genome. We also suggest that biotechnological conversion of OATs to OAOs might improve the nutritional value of Brassicales protein. HPLC-MS/MS methods for detection of these glucobarbarin products are described.
Pablo Vargas - One of the best experts on this subject based on the ideXlab platform.
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geographical speciation related to pleistocene range shifts in the western mediterranean mountains reseda sect glaucoreseda Resedaceae
Taxon, 2010Co-Authors: Santiago Martinbravo, Virginia Valcarcel, Pablo Vargas, Modesto LucenoAbstract:Reseda sect. Claucoreseda is a monophyletic group composed of five endemic tetraploid species with a disjunct distribution in the high mountains and plateaus of the Iberian Peninsula and Morocco. It was previously suggested that range shifts induced by Quaternary glaciations played an important role in the speciation of the group. We studied the evolution of R. sect. Glaucoreseda in order to infer historical range dynamics and speciation processes, and to understand current distributional patterns. Phylogeographic analyses were performed using nuclear ribosomal ITS and plastid trnL-F and rps16 sequences. Cloning of additive ITS sequences was carried out to elucidate the origin of intra-individual polymorphisms. A dated phylogeny based on ITS and cpDNA (rbcL, matK, trnL-F) sequences was used to estimate divergence times of R. sect. Glaucoreseda. Time estimates using Penalized Likelihood analyses indicate a late Pleistocene diversification of R. sect. Glaucoreseda. Incomplete lineage sorting of ancestral polymorphisms due to recent divergence, rather than rampant hybridisation, is suggested as the main cause of the phylogenetic incongruence detected between nuclear and plastid datasets. Our results support the vicariance hypothesis for population disjunctions in the Iberian Peninsula, in which an ancestral, widespread species could have undergone differentiation by Quaternary interglacial fragmentation. In contrast, long-distance dispersal across the Strait of Gibraltar may have been involved in the colonisation of North African plateaus by R. battandieri.
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is oligomeris Resedaceae indigenous to north america molecular evidence for a natural colonization from the old world
American Journal of Botany, 2009Co-Authors: Santiago Martinbravo, Pablo Vargas, Modesto LucenoAbstract:Oligomeris linifolia constitutes one of the few examples of intercontinental disjunctions at the species level between the arid regions of the Old World and SW North America. The status of the American populations has been obscure, with some authors considering the populations to be introduced, whereas others believe them to be native. To clarify these confl icting opinions, we performed phylogeographic analyses using nuclear ribosomal ITS and plastid trnL-F and rps16 sequences to infer the origin of the disjunct American populations. Two independent molecular clock approaches based on ITS and cpDNA sequences ( rbcL , matK , trnL-F ) were used to estimate a divergence time of O. linifolia . Low levels of sequence divergence and estimates of relatively recent splits of Oligomeris lineages disagree with the vicariance hypotheses traditionally suggested to account for New – Old World disjunctions. In addition, signifi cant genetic differentiation of American populations does not indicate a recent anthropogenic introduction. Morphological uniformity and the sharing of haplotypes between disjunct populations, together with the molecular clock results, suggest that a long-distance dispersal event from the Old Word to SW North America may have taken place during the Quaternary, in spite of limited dispersal mechanisms in Oligomeris .
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molecular systematics and biogeography of Resedaceae based on its and trnl f sequences
Molecular Phylogenetics and Evolution, 2007Co-Authors: Santiago Martinbravo, Harald Meimberg, Modesto Luceno, Wolfgang Markl, Virginia Valcarcel, Christian Brauchler, Pablo Vargas, Gunther HeublAbstract:Abstract The Resedaceae, containing 6 genera and ca. 85 species, are widely distributed in the Old World, with a major center of species diversity in the Mediterranean basin. Phylogenetic analyses of ITS and plastid trnL–trnF sequences of 66 species from all genera of the Resedaceae reveal (1) monophyly of the family, in congruence with preliminary phylogenetic studies; (2) molecular support for the traditional morphological subdivision of the Resedaceae into three tribes according to ovary and placentation types, and carpel number; (3) two monophyletic genera (Caylusea, Sesamoides), and one natural group (core Reseda), which includes the remaining four genera of the family (Ochradenus, Oligomeris, Randonia, Reseda); (4) a monophyletic origin for four of the six taxonomic sections recognized within Reseda (Leucoreseda, Luteola, Glaucoreseda, Phyteuma). Our results lead us to interpret an increment of the basic chromosome number in the family from x = 5 to x = 6 in at least two independent instances, and a broad representation of polyploids in multiple lineages across phylogenies, including association between octoploids and alien invasion in many parts of the world. Species diversity, endemism number, phylogenetic relationships and sequence divergence in Resedaceae suggest two major centers of differentiation, one in the western Mediterranean, and the other in the eastern Mediterranean and SW Asia. Two independent colonization events to the Canary Islands from Africa are indicated for the two Canarian Reseda endemics.
Gunther Heubl - One of the best experts on this subject based on the ideXlab platform.
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molecular systematics and biogeography of Resedaceae based on its and trnl f sequences
Molecular Phylogenetics and Evolution, 2007Co-Authors: Santiago Martinbravo, Harald Meimberg, Modesto Luceno, Wolfgang Markl, Virginia Valcarcel, Christian Brauchler, Pablo Vargas, Gunther HeublAbstract:Abstract The Resedaceae, containing 6 genera and ca. 85 species, are widely distributed in the Old World, with a major center of species diversity in the Mediterranean basin. Phylogenetic analyses of ITS and plastid trnL–trnF sequences of 66 species from all genera of the Resedaceae reveal (1) monophyly of the family, in congruence with preliminary phylogenetic studies; (2) molecular support for the traditional morphological subdivision of the Resedaceae into three tribes according to ovary and placentation types, and carpel number; (3) two monophyletic genera (Caylusea, Sesamoides), and one natural group (core Reseda), which includes the remaining four genera of the family (Ochradenus, Oligomeris, Randonia, Reseda); (4) a monophyletic origin for four of the six taxonomic sections recognized within Reseda (Leucoreseda, Luteola, Glaucoreseda, Phyteuma). Our results lead us to interpret an increment of the basic chromosome number in the family from x = 5 to x = 6 in at least two independent instances, and a broad representation of polyploids in multiple lineages across phylogenies, including association between octoploids and alien invasion in many parts of the world. Species diversity, endemism number, phylogenetic relationships and sequence divergence in Resedaceae suggest two major centers of differentiation, one in the western Mediterranean, and the other in the eastern Mediterranean and SW Asia. Two independent colonization events to the Canary Islands from Africa are indicated for the two Canarian Reseda endemics.