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- Multiplexed-shotgun-genotyping data resolve phylogeny within a very recently derived insular lineagePublication . Mort, Mark E.; Crawford, Daniel J.; Kelly, John K.; Santos-Guerra, Arnoldo; Sequeira, Miguel Menezes de; Moura, Mónica; Caujapé-Castells, JuliPremise of the study: Endemic plants on oceanic islands have long served as model systems for studying patterns and processes of evolution. However, phylogenetic studies of island plants frequently illustrate a decoupling of molecular divergence and ecological/morphological diversity, resulting in phylogenies lacking the resolution required to interpret patterns of evolution in a phylogenetic context. The current study uses the primarily Macaronesian fl owering plant genus Tolpis to illustrate the utility of multiplexed shotgun genotyping (MSG) for resolving relationships at relatively deep (among archipelagos) and very shallow (within archipelagos) nodes in this small, yet diverse insular plant lineage that had not been resolved with other molecular markers. • Methods: Genomic libraries for 27 accessions of Macaronesian Tolpis were generated for genotyping individuals using MSG, a form of reduced-representation sequencing, similar to restriction-site-associated DNA markers (RADseq). The resulting data fi les were processed using the program pyRAD, which clusters MSG loci within and between samples. Phylogenetic analyses of the aligned data matrix were conducted using RAxML. • Key results: Analysis of MSG data recovered a highly resolved phylogeny with generally strong support, including the fi rst robust inference of relationships within the highly diverse Canary Island clade of Tolpis . • Conclusions: The current study illustrates the utility of MSG data for resolving relationships in lineages that have undergone recent, rapid diversifi cation resulting in extensive ecological and morphological diversity. We suggest that a similar approach may prove generally useful for other rapid plant radiations where resolving phylogeny has been diffi cult.
- Phylogenetic relationships and phylogeography of relevant lineages within the complex Campanulaceae family in MacaronesiaPublication . Menezes, Tiago; Romeiras, Maria M.; Sequeira, Miguel Menezes de; Moura, MónicaMacaronesia has long been recognized as a natural model for studying evolutionary processes in plant diversification. Several studies have attempted to focus on single lineages, and few have covered the diversification of a family across all the archipela gos. We used a comprehensive sample to clarify the phylogenetic relationships and the biogeographic history of the Macaronesian Campanulaceae. Hypotheses related to the colonization of these archipelagos will be used to examine the diversification patterns of different lineages. We sequenced the ITS region and six cpDNA markers (atpB, matK, petD, rbcL, trnL-F, and psbA-trnH) from 10 Campanulaceae species, includ ing seven endemic species in Macaronesia. The phylogeny of these taxa was recon structed using maximum parsimony, maximum likelihood, and Bayesian inference. To study the relationships within each lineage, haplotype networks were calculated using NeighborNet and TCS algorithms. Moreover, data were combined with fossil informa tion to construct time-calibrated trees for the Macaronesian Campanulaceae species. The phylogenetic analyses are largely congruent with current taxon circumscriptions, and all the endemic genera formed monophyletic clades, namely Azorina in Azores; Musschia in Madeira; and Campanula in Cape Verde. The Azorina clade and the Cape Verde endemic Campanula may share a common ancestor in North Africa, and the di vergence was dated ca. 12.3 million years ago (Mya). The divergence of the Musschia clade began in the Pliocene ca. 3.4 Mya. Moreover, several examples of intraspecific variation were revealed among the native species with a clear geographic structured patterns, suggesting that cryptic diversity might exist within the native Macaronesian Campanulaceae when compared to the close mainland taxa (e.g., Campanula erinus, Trachelium caeruleum), but additional studies are needed to support the molecular data. This study highlights the power of combining data (e.g., phylogeny and diver gence times, with species distribution data) for testing diversification hypotheses within the unique Macaronesian flora, providing useful information for future conser vation efforts.
- Colonization routes, microevolutionary genetic structure and conservation concerns in a remote widespread insular endemic grass: the case of the Azorean tussock grass Deschampsia foliosaPublication . Moura, Mónica; Catalán, Pilar; Brehm, António; Sequeira, Miguel Menezes dePopulation genetic structure and diversity and phylogeographical dispersal routes were assessed for the Azorean endemic grass Deschampsia foliosa using AFLP markers. This species occurs on seven islands in the archipelago and a sampling of populations from the three main geographical groups of islands was used, covering its known distribution. Principal coordinates analyses (PCoAs), Bayesian analyses and phylogenetic networks revealed different degrees of admixture for the central group (C) populations and a clear differentiation for the western group (W) and São Miguel island (in the eastern group, E) populations. The best K values corresponded to nine and 11 genetic groups, which were also confirmed by analysis of molecular variance. A low but significant correlation between genetic data and geography was observed, with most relevant barriers to gene flow generally placed between sub archipelagos. We suggest a west-to-east isolation by distance dispersal model across an island age continuum with Flores–Corvo (W) and Pico (C) at the extremes of the dispersal path. An alternative scenario, also supported by the genetic data, implies an initial colonization of São Jorge (C), dispersal within C and following bidirectional dispersal to the W and E. The phylogeographical framework detected might be related to island age and to highly destructive volcanic events, and it supports the occurrence of cryptic diversity within D. foliosa. Genetic diversity estimators were highest for Pico island populations (C), lowest for São Miguel (E) and Flores (W) populations, and more divergent for the Corvo population (W). Conservation measures should be taken to preserve the genetic structure found across sub-archipelagos and islands.
- An expanded molecular phylogeny of Plumbaginaceae, with emphasis on Limonium (sea lavenders): taxonomic implications and biogeographic considerationsPublication . Koutroumpa, Konstantina; Theodoridis, Spyros; Warren, Ben H.; Jiménez, Ares; Celep, Ferhat; Doğan, Musa; Romeiras, Maria M.; Santos-Guerra, Arnoldo; Fernández-Palacios, José María; Caujapé-Castells, Juli; Moura, Mónica; Sequeira, Miguel Menezes de; Conti, ElenaPlumbaginaceae is characterized by a history of multiple taxonomic rearrangements and lacks a broad molecular phylogenetic framework. Limonium is the most species‐ rich genus of the family with ca. 600 species and cosmopolitan distribution. Its center of diversity is the Mediterranean region, where ca. 70% of all Limonium species are endemic. In this study, we sample 201 Limonium species covering all described infra‐ generic entities and spanning its wide geographic range, along with 64 species of other Plumbaginaceae genera, representing 23 out of 29 genera of the family. Additionally, 20 species of the sister family Polygonaceae were used as outgroup. Sequences of three chloroplast (trnL‐F, matK, and rbcL) and one nuclear (ITS) loci were used to infer the molecular phylogeny employing maximum likelihood and Bayesian analyses. According to our results, within Plumbaginoideae, Plumbago forms a non‐ monophyletic assemblage, with Plumbago europaea sister to Plumbagella, while the other Plumbago species form a clade sister to Dyerophytum. Within Limonioideae, Ikonnikovia is nested in Goniolimon, rejecting its former segregation as genus distinct from Goniolimon. Limonium is divided into two major clades: Limonium subg. Pteroclados s.l., including L. sect. Pteroclados and L. anthericoides, and L. subg. Limonium. The latter is divided into three well‐supported subclades: the monospecific L. sect. Limoniodendron sister to a clade comprising a mostly non‐Mediterranean subclade and a Mediterranean subclade. Our results set the foundation for taxonomic propos‐ als on sections and subsections of Limonium, namely: (a) the newly described L. sect. Tenuiramosum, created to assign L. anthericoides at the sectional rank; (b) the more restricted circumscriptions of L. sect. Limonium (= L. sect. Limonium subsect. Genuinae) and L. sect. Sarcophyllum (for the Sudano‐Zambezian/Saharo‐Arabian clade); (c) the more expanded circumscription of L. sect. Nephrophyllum (including species of the L. bellidifolium complex); and (d) the new combinations for L. sect. Pruinosum and L. sect. Pteroclados subsect. Odontolepideae and subsect. Nobiles.
- Diversity and cytogenomic characterization of wild carrots in the Macaronesian IslandsPublication . Roxo, Guilherme; Moura, Mónica; Talhinhas, Pedro; Costa, José Carlos; Silva, Luís; Vasconcelos, Raquel; Sequeira, Miguel Menezes de; Romeiras, Maria ManuelThe Macaronesian islands constitute an enormous reservoir of genetic variation of wild carrots (subtribe Daucinae; Apiaceae), including 10 endemic species, but an accurate understanding of the diversification processes within these islands is still lacking. We conducted a review of the morphology, ecology, and conservation status of the Daucinae species and, on the basis of a comprehensive dataset, we estimated the genome size variation for 16 taxa (around 320 samples) occurring in different habitats across the Macaronesian islands in comparison to mainland specimens. Results showed that taxa with larger genomes (e.g., Daucus crinitus: 2.544 pg) were generally found in mainland regions, while the insular endemic taxa from Azores and Cabo Verde have smaller genomes. Melanoselinum decipiens and Monizia edulis, both endemic to Madeira Island, showed intermediate values. Positive correlations were found between mean genome size and some morphological traits (e.g., spiny or winged fruits) and also with habit (herbaceous or woody). Despite the great morphological variation found within the Cabo Verde endemic species, the 2C-values obtained were quite homogeneous between these taxa and the subspecies of Daucus carota, supporting the close relationship among these taxa. Overall, this study improved the global knowledge of DNA content for Macaronesian endemics and shed light into the mechanisms underpinning diversity patterns of wild carrots in the western Mediterranean region.
- Breeding systems in Tolpis (Asteraceae) in the Macaronesian islands: the Azores, Madeira and the CanariesPublication . Crawford, Daniel J.; Anderson, Gregory J.; Silva, Lurdes Borges; Sequeira, Miguel Menezes de; Moura, Mónica; Santos-Guerra, Arnoldo; Kelly, John K.; Mort, Mark E.Plants on oceanic islands often originate from self-compatible (SC) colonizers capable of seed set by self fertilization. This fact is supported by empirical studies, and is rooted in the hypothesis that one (or few) individuals could find a sexual population, whereas two or more would be required if the colonizers were self-incompatible (SI). However, a SC colonizer would have lower heterozygosity than SI colonizers, which could limit radiation and diver sification of lineages following establishment. Limited evidence suggests that several species-rich island lineages in the family Asteraceae originated from SI colonizers with some ‘‘leakiness’’ (pseudo-self-compatibility, PSC) such that some self-seed could be produced. This study of Tolpis (Asteraceae) in Macaronesia provides first reports of the breeding system in species from the Azores and Madeira, and additional insights into variation in Canary Islands. Tolpis from the Azores and Madeira are predominately SI but with PSC. This study suggests that the breeding sys tems of the ancestors were either PSC, possibly from a single colonizer, or from SI colonizers by multiple dis seminules either from a single or multiple dispersals. Long distance colonists capable of PSC combine the advantages of reproductive assurance (via selfing) in the establishment of sexual populations from even a single colonizer with the higher heterozygosity resulting from its origin from an outcrossed source population. Evolution of Tolpis on the Canaries and Madeira has generated diversity in breeding systems, including the origin of SC. Macaronesian Tolpis is an excellent system for studying breeding system evolution in a small, diverse lineage.
- Is there solid evidence of widespread landscape disturbance in the Azores before the arrival of the Portuguese?Publication . Elias, Rui B.; Connor, Simon E.; Góis-Marques, Carlos A.; Schaefer, Hanno; Silva, Luís; Sequeira, Miguel M.; Moura, Mónica; Borges, Paulo A. V.; Gabriel, Rosalina