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1.
2.
For the first time amplified fragment length polymorphism (AFLP) fingerprinting is applied to classify tropical African Festuca species. Five afro-alpine narrow- and two afro-montane broad-leaved species from Uganda and Ethiopia are compared to ten European grass species. A principal coordinate analysis (PCoA) accounts for 62.5% with its first three coordinates. The PCoA and the neighbor-joining (NJ) distinguish the five narrow-leaved African Festuca species from all other species. The broad-leaved African Festuca africana and Festuca simensis are linked to the broad-leaved European species through Festuca altissima and Festuca gigantea, respectively. The narrow- and broad-leaved European species are separated as expected in the NJ. One narrow-leaved African alpine species recently described appears merged (i.e. Festuca richardii with Festuca abyssinica). We provide chromosome numbers for all seven Ugandan species and compare taxonomy and AFLP classification. Our most striking result is that the narrow-leaved African Festuca species are unique and not clustering with the narrow-leaved European species.  相似文献   

3.
A new species,Festuca samensis, belonging to theF. lilloi group (subgen.Festuca), is described from the Tarija region in southern Bolivia. The limits of theFestuca lilloi group are revised andF. setifolia, which is here lectotypified, is excluded from this group. Additionally, the first Bolivian record of the Tucuman floristic elementFestuca parodiana of subgen.Subulatae is reported.  相似文献   

4.
Aim The post‐glacial range dynamics of many European plant species have been widely investigated, but information rapidly diminishes as one moves further back in time. Here we infer the historical range shifts of Laurus, a paradigmatic tree of the Tethyan flora that has covered southern Eurasia since the Oligo‐Miocene, by means of phylogenetic and phylogeographical analyses. Location Mediterranean Basin, Black Sea and Macaronesian archipelagos (Azores, Madeira, Canary Islands). Methods We analysed plastid DNA (cpDNA) sequence (trnK–matK, trnD–trnT) variation in 57 populations of Laurus and three Lauraceae genera. Phylogenetic methods (maximum parsimony and Bayesian inference) and statistical parsimony networks were used to reconstruct relationships among haplotypes. These results were contrasted with the fossil record and bioclimatic niche‐based model predictions of past distributions to infer the migration routes and location of refugia. Results The phylogenetic tree revealed monophyly for Laurus. Overall sequence variability was low within Laurus, but six different haplotypes were distinguished and a single network retrieved, portraying three lineages primarily related to geography. A strongly divergent eastern lineage occupied Turkey and the Near East, a second clade was located in the Aegean region and, lastly, a western clade grouped all Macaronesian and central and western Mediterranean populations. A close relationship was observed between the Macaronesian populations of L. azorica and the western populations of L. nobilis. Main conclusions The phylogeographical structure of Laurus preserves the imprints of an ancient contraction and break‐up of the range that resulted in the evolution of separate cpDNA lineages in its western‐ and easternmost extremes. Intense range dynamics in the western Mediterranean and multiple glacial refugia contributed to the generation and long‐term conservation of this phylogeographical pattern, as shown by the fit between the haplotype ranges and past suitable areas inferred from bioclimatic models. Finally, our results challenge the taxonomic separation of Laurus into two distinct species.  相似文献   

5.
Presence of Neotyphodium-like endophytes in European grasses   总被引:1,自引:0,他引:1  
In order to improve knowledge of Neotyphodium‐likc fungi in European grasses, microscopic detection of endophytic mycelium was achieved in living grasses and in seeds. Samples of grasses were gathered near permanent pastures or along paths in France (93 samples, 13 genera, 22 species). Typical convoluted mycelium was found inside leaf sheaths of four genera, especially in Festuca and Lolium spp. The results suggest that endophytes were present most often in the southern regions where plants may suffer from summer drought. Endophytes were looked for in 489 seed samples (63 genera, 237 species) received from 24 European botanical gardens. Neotyphodium was found in seeds of only six genera (22 species), especially in Festuca (15 species) and Lolium (three species). No endophytic mycelium was found in the other 215 species, although other work had demonstrated the presence of the fungus in 39 of the species analysed. Neotyphodium‐likc mycelium was detected for the first time in Festuca juncifolia, F. trachyphylla, F. vaginata, F. pseudodalmatica, F. rupicaprina, F. arenaria, Vulpia ciliata and Micropyrum tenellum. Further studies are needed for the correct identification of the Neotyphodium species observed.  相似文献   

6.
Aim Bryophytes exhibit apparently low rates of endemism in Macaronesia and differ from angiosperms in their diversity patterns by the widespread occurrence of endemics within and among archipelagos. This paper investigates the phylogeography of the leafy liverwort Radula lindenbergiana to determine: (1) whether or not morphologically cryptic diversification has occurred in Macaronesia, and (2) the relationships between Macaronesian and continental populations. Location Macaronesia, Europe, Africa. Methods Eighty‐four samples were collected across the species’ distribution range and sequenced at four chloroplast DNA (cpDNA) loci (atpB–rbcL, trnG, trnL and rps4). Phylogenetic reconstructions and Bayesian ancestral area reconstructions were used in combination with population genetics statistics (H, NST, FST) to describe the pattern of present genetic diversity in R. lindenbergiana and infer its biogeographic history. Results Patterns of genetic diversity in R. lindenbergiana exhibit a striking westwards gradient, wherein haplotype (0.90) and nucleotide (0.0038 ± 0.0019) diversity peak in Macaronesia, with a substantial endemic component. We found 20.9% of the genetic variance between biogeographic regions, and most pairwise FST comparisons between regions are significantly different from zero. The global NST (0.78) is significantly higher than the global FST (0.20), providing evidence for the presence of phylogeographic signal in the data. Ancestral area reconstructions suggest that the haplotypes currently found in western Europe share a Macaronesian common ancestor. Main conclusions The haplotype diversification exhibited by R. lindenbergiana in Macaronesia is comparable to that reported for many angiosperm groups at the species level. The apparent lack of radiation among Macaronesian bryophytes may thus reflect the reduced morphology of bryophytes in comparison with angiosperms. The high diversity found among Macaronesian haplotypes, especially in Madeira and the Canary Islands, and the significant NST/FST ratio between Macaronesia and all the other biogeographic regions (an indication that mutation rate exceeds dispersal rates) suggest that Macaronesian archipelagos could have served as a refugium during the Quaternary glaciations. Many haplotypes currently found in Europe share a Macaronesian common ancestor, and this further suggests that Macaronesia might have played a key role in the back‐colonization of the continent.  相似文献   

7.
Aim We used a phylogenetic framework to examine island colonization and predictions pertaining to differentiation within Macaronesian Tarphius (Insecta, Coleoptera, Zopheridae), and explain the paucity of endemics in the Azores compared with other Macaronesian archipelagos. Specifically, we test whether low diversity in the Azores could be due to recent colonization (phylogenetic lineage youth), cryptic speciation (distinct phylogenetic entities within species) or the young geological age of the archipelago. Location Macaronesian archipelagos (Azores, Madeira and the Canary Islands), northern Portugal and Morocco. Methods Phylogenetic analyses of mitochondrial and nuclear genes of Tarphius beetles of the Azores, other Macaronesian islands and neighbouring continental areas were used to investigate the origin of island biodiversity and to compare patterns of colonization and differentiation. A comparative nucleotide substitution rate test was used to select the appropriate substitution rate to infer clade divergence times. Results Madeiran and Canarian Tarphius species were found to be more closely related to each other, while Azorean taxa grouped separately. Azorean taxa showed concordance between species and phylogenetic clades, except for species that occur on multiple islands, which segregated by island of origin. Divergence time estimates revealed that Azorean Tarphius are an old group and that the most recent intra‐island speciation event on Santa Maria, the oldest island, occurred between 3.7 and 6.1 Ma. Main conclusions Our phylogenetic approach provides new evidence to understand the impoverishment of Azorean endemics: (1) Tarphius have had a long evolutionary history within the Azores, which does not support the hypothesis of fewer radiation events due to recent colonization; (2) the current taxonomy of Azorean Tarphius does not reflect common ancestry and cryptic speciation is responsible for the underestimation of endemics; (3) intra‐island differentiation in the Azores was found only in the oldest island, supporting the idea that young geological age of the archipelago limits the number of endemics; and (4) the lack of evidence for recent intra‐island diversification in Santa Maria could also explain the paucity of Azorean endemics. Phylogenetic reconstructions of other species‐rich taxa that occur on multiple Macaronesian archipelagos will reveal whether our conclusions are taxon specific, or of a more general nature.  相似文献   

8.
Aims Several bird‐pollinated or ornithophilous flowers are present on the Macaronesian archipelagos, the Canary Islands and Madeira, but absent from nearby NW Africa and Europe. In Macaronesia, no specialist nectar‐feeding birds are found, but several generalist passerine bird species visit flowers for nectar. Two hypotheses attempt to explain the origin and evolution of ornithophily in the Macaronesian flora. According to ‘the island de novo hypothesis’, bird‐flowers evolved from mainland insect‐pollinated ancestors after island colonization. Alternatively, ancestors of the ornithophilous Macaronesian plant species evolved bird‐flowers before reaching the islands (‘the relict hypothesis’). In this study we first compile information of Macaronesian bird–flower interactions from the literature and our own field observations. Secondly, we discuss the two hypotheses of origin of ornithophily in the light of evidence from recent molecular plant phylogenies, palaeontology, historical biogeography of the African avifauna and flora, and present‐day ecological patterns. Location Madeira and Canary Islands. Results At least eleven endemic Macaronesian plant species from six genera have typical ornithophilous floral traits. These genera are: Canarina and Musschia (Campanulaceae), Isoplexis (Scrophulariaceae), Echium (Boraginaceae), Lotus (Fabaceae) and Lavatera (Malvaceae). These lineages have clear affinities to the Mediterranean region, except for Canarina whose closest relatives grow in East African mountains. Six generalist passerine bird species of Sylvia, Phylloscopus (Sylviidae), Serinus (Fringillidae) and Parus (Paridae) visit this flora for nectar. Main conclusion We suggest that the origin and evolution of ornithophilous traits in these plant species took place mostly in mainland areas prior to island colonization. In Canarina and Lavatera, it is well supported that ornithophily is a relict condition, which originated in mainland areas possibly in association with specialist nectar‐feeding birds. For the remaining plant species except Echium wildpretii bird floral traits probably also are a relict condition. These species may be derived from ancestors, which were visited by specialist nectar‐feeding birds during geological periods when the Mediterranean and the Ethiopian vegetation were intermingled in mainland Africa. Probably, these mainland ancestors went extinct due to severe climatic fluctuations, while their Macaronesian descendants survived in ‘refuge’ on the islands. Finally, the island de novo hypothesis may explain the evolution of a mixed bird/insect‐pollination system in the neo‐endemic red‐flowered Echium wildpretii.  相似文献   

9.
Ma C  Yang P  Jiang F  Chapuis MP  Shali Y  Sword GA  Kang L 《Molecular ecology》2012,21(17):4344-4358
The migratory locust, Locusta migratoria, is the most widely distributed grasshopper species in the world. However, its global genetic structure and phylogeographic relationships have not been investigated. In this study, we explored the worldwide genetic structure and phylogeography of the locust populations based on the sequence information of 65 complete mitochondrial genomes and three mitochondrial genes of 263 individuals from 53 sampling sites. Although this locust can migrate over long distances, our results revealed high genetic differentiation among the geographic populations. The populations can be divided into two different lineages: the Northern lineage, which includes individuals from the temperate regions of the Eurasian continent, and the Southern lineage, which includes individuals from Africa, southern Europe, the Arabian region, India, southern China, South‐east Asia and Australia. An analysis of population genetic diversity indicated that the locust species originated from Africa. Ancestral populations likely separated into Northern and Southern lineages 895 000 years ago by vicariance events associated with Pleistocene glaciations. These two lineages evolved in allopatry and occupied their current distributions in the world via distinct southern and northern dispersal routes. Genetic differences, caused by the long‐term independent diversification of the two lineages, along with other factors, such as geographic barriers and temperature limitations, may play important roles in maintaining the present phylogeographic patterns. Our phylogeographic evidence challenged the long‐held view of multiple subspecies in the locust species and tentatively divided it into two subspecies, L. m. migratoria and L. m. migratorioides.  相似文献   

10.
11.
Morphological and seed protein analyses of 26 species of the generaLolium, Festuca andVulpia confirmed their close systematic affinities. Six inflorescence characters readily differentiatedFestuca fromLolium. Protein similarities betweenFestuca of sect.Bovinae and cross-pollinated species ofLolium, coupled with cytogenetic and crossability data, substantiate that they should be united into one genus.Vulpia had phenetic similarities with sect.Scariosae, Montanae andOvinae ofFestuca. Lolium, Festuca, andVulpia are most likely derived from a common ancestral form which was close toFestuca pratensis andLolium perenne.  相似文献   

12.
Aim We reconstructed the phylogeny of the lichen genus Nephroma (Peltigerales) to assess the relationships of species endemic to Macaronesia. We estimated dates of divergences to test the hypothesis that the species arose in Macaronesia (neo‐endemism) versus the oceanic archipelagos serving as refugia for formerly widespread taxa (palaeo‐endemism). Location Cosmopolitan with a special focus on the archipelagos of the Azores, Madeira and the Canary Islands. Methods DNA sequences were obtained from 18 species for three loci and analysed using maximum parsimony, maximum likelihood and Bayesian inferences. Divergence dates were estimated for the internal transcribed spacer (ITS)‐based phylogeny using a relaxed molecular clock. Reconstruction of the ancestral geographical range was conducted using the Bayesian 50% majority rule consensus tree under a parsimony method. Results The backbone phylogenetic tree was fully supported, with Nephroma plumbeum as sister to all other species. Four strongly supported clades were detected: the Nephroma helveticum, the N. bellum, the N. laevigatum and the N. parile clades. The latter two share a common ancestor and each includes a widespread Holarctic species (N. laevigatum and N. parile, respectively) and all species endemic to Macaronesia. The data suggest a neo‐endemic origin of Macaronesian taxa, a recent range expansion from Macaronesia of both widespread species, a range expansion limited to the Mediteranean Basin and south‐western Europe for another taxon, and a long dispersal event that resulted in a speciation event in the western parts of North America. Main conclusions The Macaronesian endemic species belong to two sister clades and originated from a most recent common ancestor (MRCA) shared with one widely distributed taxon, either N. parile or N. laevigatum. Estimates of the mean divergence dates suggest that the endemics originated in the archipelagos after the rise of the volcanic islands, along with the ancestor to the now widespread species, which probably expanded their range beyond Macaronesia via long‐distance dispersal. This study provides the first phylogenetic evidence of Macaronesian neo‐endemism in lichenized fungi and provides support for the hypothesis that oceanic islands may serve as a source for the colonization of continents. However, further data are needed to properly assess the alternative hypothesis, namely colonization from western North America.  相似文献   

13.
Historical sea levels have been influential in shaping the phylogeography of freshwater‐limited taxa via palaeodrainage and palaeoshoreline connections. In this study, we demonstrate an approach to phylogeographic analysis incorporating historical sea‐level information in a nested clade phylogeographic analysis (NCPA) framework, using burrowing freshwater crayfish as the model organism. Our study area focuses on the Bass Strait region of southeastern Australia, which is marine region encompassing a shallow seabed that has emerged as a land bridge during glacial cycles connecting mainland Australia and Tasmania. Bathymetric data were analysed using Geographical Information Systems (GIS) to delineate a palaeodrainage model when the palaeocoastline was 150 m below present‐day sea level. Such sea levels occurred at least twice in the past 500 000 years, perhaps more often or of larger magnitude within the last 10 million years, linking Victoria and Tasmania. Inter‐locality distance measures confined to the palaeodrainage network were incorporated into an NCPA of crayfish (Engaeus sericatus Clark 1936) mitochondrial 16S rDNA haplotypes. The results were then compared to NCPAs using present‐day river drainages and traditional great‐circle distance measures. NCPA inferences were cross‐examined using frequentist and Bayesian procedures in the context of geomorphological and historical sea‐level data. We found distribution of present‐day genetic variation in E. sericatus to be partly explained not only by connectivity through palaeodrainages but also via present‐day drainages or overland (great circle) routes. We recommend that future studies consider all three of these distance measures, especially for studies of coastally distributed species.  相似文献   

14.
Abstract

Festuca alpestris R. et S. in the Alps near Belluno.—Some populations of Festuca from the F. varia aggr. occurring in the south-eastern Alps near Belluno have been recognized as belonging to F. alpestris R. et S. The relationships between this species and F. calva (Hackel) Richter from the Julian Alps are discussed and the diacritic characters are newly defined.  相似文献   

15.
This paper provides comparative information on the reproductive biology of the alfonsino, Beryx splendens Lowe, 1834, species with commercial interest in the Azores, Madeira and the Canary Islands. A total of 846 individuals from Azores (14.0–42.0 cm fork length), 621 from Madeira (17.2–50.0 cm fork length) and 643 from the Canaries (18.2–38.9 cm fork length) were used for the study. The alfonsino is gonochoric with no evidence of sexual dimorphism. Females are more abundant than males; this dominance probably reflects certain differences in the spatial distribution and/or the catchability of males and females in the Macaronesian archipelagos. The spawning season was distinct for the three Macaronesian areas, with an observed North–South variation in the reproductive period: September–March in the Azores, March–June in Madeira and July–September in the Canary Islands. The size at sexual maturity estimated for Madeira and the Canary Islands is similar (32 and 30 cm fork length, respectively), while for the Azores it is reached at smaller length (23 cm fork length). The differences observed in the size at sexual maturity can be explained by the different exploitation levels in each archipelago. Life‐history parameters of the alfonsino suggest that this species has a specialistic life‐history strategy and fisheries based on this species are more susceptible to growth overfishing and population depletion.  相似文献   

16.
Repetitive DNA sequences contribute considerably to an understanding of the genomes of higher plants. Repetitive DNA sequences tend to be genome-specific due to the rate of amplification and extent of divergence. Two genome-specific probes from the genomic DNA library of Festuca arundinacea var. genuina Schreb.were selected and characterized. TF521 was found to be P genome-specific since it was able to hybridize with Festuca pratensis Huds. (PP) and Festuca arundinacea var. genuina (PPG1G1G2G2), but not, or only weakly, with tetraploid Festuca species. TF521 hybridized only with the diploid Festuca and not with the Lolium species (LL). TF436 was specific to tetraploid species of Festuca, such as F. arundinacea var. glauces-cens Boiss. (G1G1G2G2) and Festuca mairei St. Yves (M1M1M2M2). By means of Southern hybridization, TF436 was used to detect chromatin introgression of F. mairei in the progenies of the hybrid F. mairei×Lolium perenne L. Potential addition and translocation lines were identified in the BC1F1 derivatives of F. mairei×L. perenne. In situ hybridization was used to confirm the genetic identity of these lines. Sequence analyses indicated that TF436 and TF521 were two novel DNA sequences as no homologous sequences were found in Genebank. Received: 22 June 2000 / Accepted: 3 November 2000  相似文献   

17.
Morphological and seed protein studies of selected species ofFestuca were performed to elucidate the relationships between species of sect.Ovinae and their affinity with other fescues.Festuca rubra andF. heterophylla (extravaginale group) had higher phenetic affinity with taxa of sect.Scariosae, Montanae andBovinae than with members of their own section. 5 species of the intravaginale group (F. ovina, F. capillata, F. valesiaca, F. sulcata, F. trachyphylla) were fairly uniform and well defined by protein and morphological data. This supports current systematic thinking and does not agree withHackel's (1882) classification of this group.  相似文献   

18.
Macaronesian archipelagos stand apart from other oceanic islands reputed as laboratories for the study of evolution by their proximity to the mainland, lack of subsidence, and steep ecological gradients. The genus Pholcus Walckenaer, 1805, commonly known as daddy-long-leg spiders, is one of the most speciose arthropod groups in the region, with 25 endemic species. In the present study, we use information from four mitochondrial genes, along with morphological data, to examine the phylogenetic relationships and diversification patterns of the genus in the region. Phylogenetic analyses support monophyly of Macaronesian Pholcus including the Moroccan species Pholcus vachoni and hence a single colonization event in the archipelagos. Madeira colonizers most likely originated from the Canaries, and a back-colonization of the nearby mainland receives further support. Estimated lineage divergence times suggest a long-time presence of Pholcus in the region, but also reveal that most present-day species are the result of recent, and probably rapid, speciation events. Diagnostic characters among Macaronesian Pholcus are confined to structures involved in copulation. Coupled with the extremely high diversification rate, the highest recorded for spiders, these copulatory characters suggest that sexual selection has played a key role in the local diversification of Pholcus in Macaronesia.  相似文献   

19.
Aim Endemism in the flora of the Azores is high (33%) but in other respects, notably the paucity of evolutionary radiations and the widespread distribution of most endemics, the flora differs markedly from the floras of the other Macaronesian archipelagos. We evaluate hypotheses to explain the distinctive patterns observed in the Azorean endemic flora, focusing particularly on comparisons with the Canary Islands. Location Azores archipelago. Methods Data on the distribution and ecology of Azorean endemic flowering plants are reviewed to ascertain the incidence of inter‐island allopatric speciation and adaptive, ecological speciation. These are contrasted with patterns for the Canary Islands. Patterns of endemism in the Azores and Canaries are further investigated in a phylogenetic context in relation to island age. beast was used to analyse a published molecular dataset for Pericallis (Asteraceae) and to investigate the relative ages of Azorean and Canarian lineages. Results There are few examples of inter‐island allopatric speciation in the Azorean flora, despite the considerable distances between islands and sub‐archipelagos. In contrast, inter‐island allopatric speciation has been an important process in the evolution of the Canary Islands flora. Phylogenetic data suggest that Azorean endemic lineages are not necessarily recent in origin. Furthermore, in Pericallis the divergence of the Azorean endemic lineage from its closest relative pre‐dates the radiation of a Canarian herbaceous clade by inter‐island allopatric speciation. Main conclusions The data presented do not support suggestions that hypotheses pertaining to island age, age of endemic lineages and ecological diversity considered individually explain the lack of radiations and the widespread distribution of Azorean endemics. We suggest that palaeoclimatic variation, a factor rarely considered in macroecological studies of island diversity patterns, may be an important factor. Palaeoclimatic data suggest frequent and abrupt transitions between humid and arid conditions in the Canaries during the late Quaternary, and such an unstable climate may have driven the recent diversification of the flora by inter‐island allopatric speciation, a process largely absent from the climatically more stable Azores. Further phylogenetic/phylogeographic analyses are necessary to determine the relative importance of palaeoclimate and other factors in generating the patterns observed.  相似文献   

20.
The Macaronesian endemic flora has traditionally been interpreted as a relict of a subtropical element that spanned across Europe in the Tertiary. This hypothesis is revisited in the moss subfamily Helicodontioideae based on molecular divergence estimates derived from two independent calibration techniques either employing fossil evidence or using an Monte Carlo Markov Chain (MCMC) to sample absolute rates of nucleotide substitution from a prior distribution encompassing a wide range of rates documented across land plants. Both analyses suggest that the monotypic Madeiran endemic genus Hedenasiastrum diverged of other Helicodontioideae about 40 million years, that is, well before Macaronesian archipelagos actually emerged, in agreement with the relict hypothesis. Hedenasiastrum is characterized by a plesiomorphic morphology, which is suggestive of a complete morphological stasis over 40 million years. Macaronesian endemic Rhynchostegiella species, whose polyphyletic origin involves multiple colonization events, evolved much more recently, and yet accumulated many more morphological novelties than H. percurrens. The Macaronesian moss flora thus appears as a complex mix of ancient relicts and more recently dispersed, fast‐evolving taxa.  相似文献   

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