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1.
Abstract

Antirrhinum lopesianum Rothm. is a narrow endemic of the Lusitan Duriensean biogeographical sector (central western Spain and north-eastern Portugal). The species is listed as threatened in several Spanish documents, although it does not figure as such in any Portuguese document. This paper provides a detailed study of its distribution, estimates of the sizes of its populations, the threats it faces, and its current conservation status. The total number of individuals thought to exist is only 768, distributed along the valley of the River Duero on the Spanish – Portuguese border (562, 71.2%), and in the Portuguese Sabor River valley (206, 26.8%). The main threat to the species is loss of habitat: about one third of the Iberian populations can be considered threatened; one population containing 37.6% of all these plants (289) is severely threatened. To determine the Area of Occupancy and the Extent of Occurrence, an exhaustive bibliographical survey was carried out, and herbarium specimens deposited in several institutions were revised. It is, therefore, classifiable as Critically Endangered in Portugal and Endangered in Spain.  相似文献   

2.
The western Ordos plateau in the central-north of China is abundant in relic shrub species. Totally 54 shrub species belonging to 31 genera in 16 families are found in 10 desert shrub communities,including 10 local endemic species, five relic shrub species, and seven threatened species defined by the China Red Data Book. The percentage of the threatened shrub species to the total is as high as 12.9%, much greater than the national average (3.5%). Although a National Natural Reserve has been established since 1998 in the western Ordos plateau, the exploitation of mining resources continues to expand at a significant biological cost. Given the circumstances, future conservation efforts should focus on (1) removing coking and cement facilities from the reserve; (2) defining the boundaries of the Western Ordos National Natural Reserve encompassing all habitats where these shrub species occur; (3) implementing comprehensive plans coupling conservation with economic development; (4) enforcing ecological restoration after mining; and (5)␣establishing comprehensive population monitoring systems and promoting ex situ conservation. In addition, two local endemic relic species (Tetraena mongolica and Helianthemum ordosicum), which were defined as rare species in the second conservation priority by the China Red Data Book, should be considered as endangered species in the first conservation priority rank due to the extremely restricted distribution ranges, extremely scarce populations and more prominently, the currently increasing human disturbances caused by mining and urbanization in the core conservation area of the western Ordos plateau.  相似文献   

3.
The Iberian Peninsula is home to a large number of endemic species that often show strong genetic subdivisions which indicate possible isolation of populations in the past. Numerous phylogeographic and phylogenetic studies on Iberian flora and fauna have revealed this territory to be the origin of genetic differentiation during the Pleistocene Ice Age. To better understand the influence of Plio-Pleistocene climatic oscillations on the cladogenesis and population structuring of refugial taxa restricted to freshwaters of the Iberian Peninsula, we studied the evolutionary history of the small European genus Baldellia, both from a phylogenetic/phylogeographic perspective and regarding its ecological characteristics. Molecular analyses were based on four plastid regions and nuclear ITS2 ribosomal spacer from individuals belonging to geographically isolated Baldellia populations, while the relationships between climate and Baldellia species distribution was investigated by redundancy analysis applied to the climatic data with the occurrence of Baldellia species as external variables. The absence of a clear phylogenetic signal most likely reflects a common and recent cladogenesis for Baldellia. In contrast, the more rapidly evolving plastid sequences indicate a recent phylogeographic history of refugial repartition and ecological segregation probably occurring during the last glaciation, a scenario well supported by marked differences in species?? ecological preferences and climate analysis.  相似文献   

4.
Native grasslands are one of the most endangered ecosystems in North America. In this study, we examined the ecological and evolutionary roles of endangered and threatened (e/t) grasses by establishing robust evolutionary relationships with other nonthreatened native and introduced grass species of the community. We hypothesized that the phylogenomic distribution of e/t species of grasses in Illinois would be phylogenetically clustered because closely related species would be vulnerable to the same threats and have similar requirements for survival. This study presents the first time a phylogeny based on complete plastome DNA of Poaceae was analyzed by phylogenetic diversity analysis. To avoid the disturbance of e/t populations, DNA was extracted from herbarium specimens. Next‐generation sequencing (NGS) techniques were used to sequence DNA of plastid genomes (plastomes). The resulting phylogenomic tree was analyzed by phylogenetic diversity metrics. The extracted DNA successfully produced complete plastomes demonstrating that herbarium material is a practical source of DNA for genomic studies. The phylogenomic tree was strongly supported and defined Dichanthelium as a separate clade from Panicum. The phylogenetic metrics revealed phylogenetic clustering of e/t species, confirming our hypothesis.  相似文献   

5.
The aim of this study is to determine the conservation status of Scrophularia valdesii Ortega-Olivencia & Devesa, a threatened narrow endemism of the Duero Basin (central-western Spain and north-eastern Portugal, Lusitan Duriensean biogeographical sector), by using the IUCN (2001) IUCN Red List Categories and Criteria: version 3.1. IUCN Species Survival Commision. IUCN, Gland, Switzerland and Cambridge, UK. The species is listed as threatened in several Spanish compilatory works on threatened flora, such as `The Spanish Red List of Vascular Flora' and the `Atlas and Red Book of Threatened Vascular Flora of Spain', although it does not figure as such in any Portuguese document. Here we report detailed studies of its distribution, and assess its current conservation status with respect to this, the sizes of its populations, and the threats it faces. Our estimation of the size of the Iberian populations was based on our own census data from those sites at which we found the species. All censuses were performed by direct counting of all potentially reproductive individuals. Fourteen populations were found, and the total members thought to exist are 161, with a highly fragmented distribution on the Spanish–Portuguese border along the valley of the River Duero. Exhaustive bibliographical and field surveys were carried out and herbarium specimens housed in several herbaria were revised in order to determine the Extent of Occurrence and the Area of Occupancy. Based on our data, the species is classifiable as Critically Endangered and Endangered in Portugal and Spain, respectively. The risk of local population extinction is high due to its typically small local population sizes and suitable conservation strategies should be developed in order to preserve the species.  相似文献   

6.
The latest publications on Sarcocornia taxonomy and phylogeny recognize six taxa in this genus on the Iberian Peninsula: S. perennis, S. fruticosa, S. alpini, S. alpini subsp. carinata, S. hispanica, and S. pruinosa. The present study represents a comprehensive revision of the different taxa in the Sarcocornia genus present in Western Mediterranean Europe by means of morphological, micromorphological and phylogenetic internal transcribed spacer (ITS) analysis. Morphological and micromorphological data were studied from Sarcocornia samples from 113 populations in coastal salt marshes and inland salt pans in Portugal, France, Spain and Italy. Sixteen new ITS sequences were obtained from Mediterranean Sarcocornia species and analysed together with previous reported data. Published karyological, ecological and biogeographical data from Western Mediterranean Europe were also reviewed. The results indicate the presence of a new species, S. lagascae, found growing in coastal Mediterranean areas of the Iberian Peninsula. The species S. fruticosa was found to be absent from the Iberian territories.  相似文献   

7.
The Iberian wolf (Canis lupus signatus), an endemic subspecies of the Iberian Peninsula, is endangered in Portugal. Contrary to the rest of Europe, the distribution of this subspecies has been declining in Portugal throughout the twentieth century to the present day. Knowledge of the Iberian wolf in Portugal is limited and this lack of detailed scientific knowledge makes it difficult to evaluate conservation priorities. To fill this gap, we summarize existing knowledge regarding trends and potential threats and provide a perspective on Iberian wolf population trends in Portugal, identifying potential factors modulating such trends. Priorities for research and existing monitoring gaps are presented. Declines are primarily associated with a scarcity of wild prey with consequent livestock predation, and illegal persecution primarily in retaliation for predation on livestock. If these limiting causal factors continue operating, Iberian wolf survival in Portugal is jeopardized. Wolf conservation will benefit from a long-term project including public awareness, scientific research and conservation and management solutions to protect this endangered subspecies. Future research should focus on the mechanisms regulating population size, territory occupancy and interactions with prey species, both domestic and wild.  相似文献   

8.
The knowledge of the historical range of organisms is necessary to understand distribution dynamics and their drivers as well as to set reference conditions and conservation goals. We reviewed written sources documenting the presence of lynxes in Spain between the sixteenth and nineteenth centuries, trying to infer whether Lynx records referred to the Iberian (Lynx pardinus) or the Eurasian (Lynx lynx) species. We compiled 151 spatially specific, non-redundant Lynx records, dating between 1572 and 1897. Records appeared split in two neatly separated areas, North and South. Arguably, all historical records from the South area correspond to Iberian lynx, since almost all of them fall within the estimated range of the species in the 1950s. This suggests that the core distribution area of the species remained relatively stable for centuries, until the second half of the twentieth century. The reported range in the 1950s is thus an appropriate scenario to set conservation goals for this critically endangered species. The North area extended from Galicia and northern Portugal to the Mediterranean, mainly occupying the Atlantic-climate area of northern Iberia. Reported direct measurements and the accumulation of indirect evidences suggest that most, if not all, northern Lynx records refer to the Eurasian lynx, which had been previously detected in archaeological sites of the area. This species was apparently present in the Iberian Peninsula until the early-nineteenth century. Our results provide an objective, baseline distribution of Lynx species in Spain useful to guide conservation efforts both at the Iberian and European levels.  相似文献   

9.
Phylogeny is vitally important to evaluate evolutionary distinctiveness and conservation priorities of species. Najas ancistrocarpa is one of the rarest and least known East Asian species of the c. 30–40 species of the aquatic plant genus Najas (Hydrocharitaceae). We used a recently discovered collection of this nationally and regionally endangered species in Japan and East Asia to assess whether N. ancistrocarpa is a distinct species or an untypical form of other Najas species and to evaluate its conservation priority in a phylogenetic context. The sample set of our previous study, exploring worldwide phylogeny of the genus was used with N. ancistrocarpa to delimit species boundaries in Najas and obtain conservation priority scores, calculated by multiplying evolutionary distinctiveness and global extinction risks converted from Red List categories. We performed molecular phylogenetic analyses of plastid (ptDNA) and nuclear (ITS) DNA datasets, STACEY species delimitation analysis using the multilocus dataset and a measurement of conservation priority with Tuatara. Najas ancistrocarpa was consistently placed in ptDNA and ITS trees. Species delimitation analysis objectively assessed that N. ancistrocarpa is phylogenetically distinct. Phylogenetic conservation prioritization ranked N. ancistrocarpa the second highest priority species of the genus Najas. Overall, in terms of biodiversity conservation, N. ancistrocarpa represents an important Najas species in Japan and probably the world.  相似文献   

10.
The phylogeography of wild boars (WB) and domestic pigs (Sus scrofa) has contributed important insights into where and when domestication occurred. The geographic distribution of two core haplotypes (E1a and E1c) of the main European phylogenetic clade suggests that Central Europe was an early domestication centre, although the complexity of the pattern does not exclude the possibility that multiple domestication events occurred in different regions. To investigate the relationships among WB and domestic pig breeds in Iberia, a fragment of the mitochondrial DNA control region from a large sample (n = 409) of WB and local pig breeds was co‐analysed with published sequences from other European populations. The Iberian sample revealed a high frequency of a sub‐cluster (E1c) of the European haplogroup E1 in 77% of total Iberian samples, 96% of WB, 90% of Alentejano (Portugal) and 87% of Iberian breed pigs (Spain; Black Hairy, Black Hairless and Red varieties). Low genetic distance (FST = 0.105) was observed between Alentejano (Portugal) and Iberian breed pigs (Spain). Alentejano and Iberian breed pigs showed low genetic distances to both Iberian and Central European WB (average FST = 0.345 and 0.215, respectively). This pattern suggests that early pig husbandry in the Iberian Peninsula did not solely rely on imported Central European stock, but also included the recruitment of local WB.  相似文献   

11.
Narrow endemics constitute the cornerstone of Mediterranean plant diversity. Naufraga balearica (Apiaceae) is a critically endangered, extremely narrow endemic plant from the western Mediterranean island of Majorca. Because the species belongs to a monotypic genus, N. balearica was hypothesized to be a palaeoendemism. Here we conducted phylogenetic dating, population genetic and climatic niche analyses in order to understand the evolutionary history and conservation perspectives of this flagship species. Phylogenetic dating analysis of nuclear and plastid DNA sequences revealed a late Miocene to early Pliocene divergence between Naufraga and its sister genus Apium, supporting the palaeoendemic status of the former. Amplified fragment length polymorphism (AFLP) markers and plastid DNA sequences of the five Naufraga populations revealed moderate genetic diversity. This diversity is in line with that of other palaeoendemisms from western Mediterranean islands, as revealed by a comparison with 22 other narrow endemic species from this region. Despite the fact that all Naufraga populations are located at a maximum distance of 10 km in a straight line, a strikingly strong population differentiation was found for AFLP markers, which is explained by long-term isolation likely related to short-range pollination and dispersal strategies of the species. While the species is not genetically impoverished, species distribution modelling and microclimatic monitoring revealed that narrow ecological requirements underlie the current extreme rarity of Naufraga and may jeopardize its long-term survival. Our results indicate that a multidisciplinary approach provides powerful tools to develop conservation strategies for evolutionarily singular lineages.  相似文献   

12.
The latest IUCN statistics show that of over 12,000 plant species, 70% are threatened, 19% are critically endangered and 28 species are extinct in the wild. Target 8 of the Global Strategy for Plant Conservation (GSPC) highlights the importance of ex situ conservation of critically endangered plants. Long-term germplasm storage for species with recalcitrant seeds needs alternative measures. In vitro methods complement seed banking and other ex situ measures and are vital for long-term conservation. Conservation Biotechnology at RBG Kew is currently working on a number of rare and threatened recalcitrant species from biodiversity-rich areas of the world to develop good quality in vitro propagules for cryopreservation, recovery and restoration projects. The importance of successful in vitro propagation methods, transplantation technologies, cryopreservation and international networking for the integrated conservation of these species are discussed in detail.  相似文献   

13.
The funnel-web spider genus Macrothele is the only representative of the mygalomorph family Hexathelidae not found in Australia or New Zealand. Its 26 species occur in Central Africa and the Oriental region. Two Macrothele species are found in Europe: M. cretica Kulczynski, 1903 from Crete, and M. calpeiana (Walckenaer, 1805) type species of the genus and the largest European spider, whose distribution extends across the south-eastern Iberian Peninsula, and in two localities of North Africa. Macrothele calpeiana is the only spider protected under European legislation. The fragmentation and destruction of the cork oak forest, with which M. calpeiana was thought to be closely associated, prompted the inclusion of this species in the Bern Convention. Some authors, however, have challenged this view and consider M. calpeiana to be neither a cork oak forest bioindicator nor an endangered species. By contrast, other observations suggest that the distribution of the species is extremely fragmented and that most local populations should be considered as threatened. In this paper, we examine aspects of the conservation status of M. calpeiana in the light of molecular phylogenetic analyses based on mitochondrial markers of sample specimens from major populations. Our data confirm the fragmented distribution of M. calpeiana and reveal high levels of genetic differentiation across its populations. Local population growth cannot be ruled out, though the lineage as a whole has apparently not undergone population growth. Lineage age estimates suggest that M. calpeiana colonized the Iberian Peninsula during the Messinian salinity crisis and that the current population fragmentation originates from the Pliocene and Pleistocene. We argue that the fragmentation and deep genetic divergence across populations, along with evolutionary singularity and endemicity in one of Europe’s main biodiversity hotspots, support the preservation of its legally protected status.  相似文献   

14.
Malus sieversii, a wild progenitor of the domesticated apple, is an endangered species and is assigned second conservation priority by the China Plant Red Data Book. It is urgent to carry out in situ conservation of this species, but previous studies have not identified evolutionarily significant units (ESUs) for conservation management. In this study, we investigated the genetic diversity and relationships of six M. sieversii populations from China using integrated analysis of microsatellite (nSSR) data, genome‐wide SNPs and previous results in order to propose a reasonable conservation management. The results showed that levels of genetic diversity were inconsistently reflected by our nSSR and previous studies, suggesting that indices of genetic diversity are not effective to identify priority conservation areas for M. sieversii. Based on the selection criteria of ESUs for endangered species conservation, ESUs should reflect lineage divergence, geographical separation and different adaptive variation. Our phylogenetic tree based on genome‐wide SNPs yielded a clear relationship of divergent lineages among M. sieversii populations, leading to new different from those of previous studies. Three independent lineages, including the pairs of populations Huocheng‐Yining, Gongliu‐Xinyuan and Tuoli‐Emin, were identified. The geographic distances between populations among the different phylogenetic lineages were much greater than those within the same phylogenetic lineage. A cluster analysis on environmental variables showed that the three independent lineages inhabit different environmental conditions, suggesting that they may have adapted to different environments. Based on the results, we propose that three independent ESUs should be recognized as conservation units for M. sieversii in China.  相似文献   

15.
Glacial refugia protected and promoted biodiversity during the Pleistocene, not only at a broader scale, but also for many endemics that contracted and expanded their ranges within refugial areas. Understanding the evolutionary history of refugial endemics is especially important in the case of endangered species to recognize the origins of their genetic structure and thus produce better informed conservation practices. The Iberian Peninsula is an important European glacial refugium, rich in endemics of conservation concern, including small mammals, such as the Cabrera vole (Microtus cabrerae). This near‐threatened rodent is characterized by an unusual suite of genetic, life history and ecological traits, being restricted to isolated geographic nuclei in fast‐disappearing Mediterranean subhumid herbaceous habitats. To reconstruct the evolutionary history of the Cabrera vole, we studied sequence variation at mitochondrial, autosomal and sex‐linked loci, using invasive and noninvasive samples. Despite low overall mitochondrial and nuclear nucleotide diversities, we observed two main well‐supported mitochondrial lineages, west and east. Phylogeographic modelling in the context of the Cabrera vole's detailed fossil record supports a demographic scenario of isolation of two populations during the Last Glacial Maximum from a single focus in the southern part of the Iberian Peninsula. In addition, our data suggest subsequent divergence within the east, and secondary contact and introgression of the expanding western population, during the late Holocene. This work emphasizes that refugial endemics may have a phylogeographic history as rich as that of more widespread species, and conservation of such endemics includes the preservation of that genetic legacy.  相似文献   

16.
Reis DM  Cunha RL  Patrão C  Rebelo R  Castilho R 《Genetica》2011,139(9):1095-1105
The fire salamander complex is quite diverse in the Iberian Peninsula where nine subspecies of Salamandra salamandra are currently recognized. Here, we analysed the geographical distribution of the subspecies S. s. gallaica and S. s. crespoi using partial sequences of the mitochondrial cytochrome b gene of 168 individuals from 12 locations in Portugal. Our results support the existence of a deep lineage divergence between the two subspecies, with non-overlapping geographical distributions except in two contact zones: one in Sesimbra on the western coast, and another in Alcoutim on the southeastern border with Spain. Moreover, S. s. crespoi displays signs of gene flow among the sampled locations whereas S. s. gallaica shows evidence of some restriction to gene flow. Present-day genetic make-up of S. s. gallaica and S. s. crespoi is a result of past historical events, fine-tuned by contemporary Iberian geoclimate. Humid mountain areas were found to harbour increased genetic diversity possibly acting as past refugia during drier interglacial periods. To analyse wider geographical patterns and lineage splitting events within S. salamandra we performed a Bayesian dating analysis completing our data set with previously published sequences. The observed divergences were associated to successive biogeographic scenarios, and to other Iberian species showing similar trends.  相似文献   

17.
Squalius alburnoides (Steindachner, 1866) is an endemic threatened species from the Iberian Peninsula. Here, we report the first observations of intraspecific cleaning behavior in isolated summer pools in the Guadiana River Basin (Portugal). We found that focal S. alburnoides solicited cleaning by adopting an immobile tail-stand position known as “posing,” which immediately signaled a response to a few conspecifics that approached and inspect them. Our study expands the list of cleanerfish species in freshwaters, giving emphasis to the importance of mutual positive behavior within an endangered species, particularly when facing seasonal disturbance.  相似文献   

18.
The contemporary distribution and genetic composition of biodiversity bear a signature of species’ evolutionary histories and the effects of past climatic oscillations. For many European species, the Mediterranean peninsulas of Iberia, Italy and the Balkans acted as glacial refugia and the source of range recolonization, and as a result, they contain disproportionately high levels of diversity. As these areas are particularly threatened by future climate change, it is important to understand how past climatic changes affected their biodiversity. We use an integrated approach, combining markers with different evolutionary rates and combining phylogenetic analysis with approximate Bayesian computation and species distribution modelling across temporal scales. We relate phylogeographic processes to patterns of genetic variation in Myotis escalerai, a bat species endemic to the Iberian Peninsula. We found a distinct population structure at the mitochondrial level with a strong geographic signature, indicating lineage divergence into separate glacial refugia within the Iberian refugium. However, microsatellite markers suggest higher levels of gene flow resulting in more limited structure at recent time frames. The evolutionary history of M. escalerai was shaped by the effects of climatic oscillations and changes in forest cover and composition, while its future is threatened by climatically induced range contractions and the role of ecological barriers due to competition interactions in restricting its distribution. This study warns that Mediterranean peninsulas, which provided refuge for European biodiversity during past glaciation events, may become a trap for limited dispersal and ecologically limited endemic species under future climate change, resulting in loss of entire lineages.  相似文献   

19.
Maintaining living ex situ collections is one of the key conservation methods in botanic gardens worldwide. Despite of the existence of many other conservation approaches used nowadays, it offers for many endangered plants an important insurance policy for the future, especially for rare and threatened relict trees. The aim of this research was to investigate the global extent of living ex situ collections, to assess and discuss their viability and inform the development of conservation approaches that respond to latest global conservation challenges. We used as a model taxon the tree genus Zelkova (Ulmaceae). The genus includes six prominent Tertiary relict trees which survived the last glaciation in disjunct and isolated refugial regions. Our comprehensive worldwide survey shows that the majority of botanic institutions with Zelkova collections are in countries with a strong horticultural tradition and not in locations of their origin. More importantly, the acutely threatened Zelkova species are not the most represented in collections, and thus safeguarded through ex situ conservation. Less than 20% of the ex situ collections surveyed contain plant material of known wild provenance while the majority (90%) of collections are generally very small (1–10 trees). Botanic gardens and arboreta particularly in regions where iconic relict trees naturally occur should play a vital role in the conservation of these species. The coordination of conservation efforts between gardens has to be enhanced to prioritise action for the most threatened relict trees. Large scale genetic studies should be undertaken, ideally at genus level, in order to verify or clarify the provenance of ex situ collections of relict trees in cultivation. For the most threatened relict tree genera, well-coordinated specialist groups should be created.  相似文献   

20.
The Iberian wild goat (Capra pyrenaica) is an endemic species of the Iberian Peninsula. Of the four generally accepted subspecies (Capra pyrenaica victoriae, C.p. hispanica, C.p. pyrenaica, C.p. lusitanica) only two subsist (C.p. victoriae, C p. hispanica). The subspecies once found in Portugal, C. p. lusitanica, became extinct in the 19th century. However, the reintroduction of the C. p. victoriae in north-west Spain, led to the natural recolonization of this subspecies into Portugal. Knowledge of the Iberian wild goat in Portugal is still limited, making it difficult to evaluate the major conservation/management needs. To fill this gap, here we describe the historical distribution of the Iberian wild goat in Portugal and summarize the available information on the reintroduction and recolonization process of this species. Additionally, we used line itinerary survey (2011–2012), coupled with Distance Sampling, to estimate current densities, range and population structure of the Iberian wild goat distribution in Portugal. The Iberian wild goat density is 2.78/100 ha (95% CI: 1,72–4,50; CV: 18,36%) and the abundance is of 576 (CI 95%: 356–930; CV: 18,36%). The distribution data shows that the population is divided in three nuclei: 1- Serra do Gerês (13,840 ha); 2–Serra Amarela (1235 ha); 3–Castro Laboreiro (343 ha), in a total area of 15,418 ha. Iberian wild goat population in Portugal has greatly increased in the last years, both in number and distribution range. The demographic data shows a potential for increase in the next years but our current ecological background knowledge still remains limited. Iberian wild goat management will benefit from a long-term project including public awareness, scientific research and management solutions.  相似文献   

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