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P. CUBAS C. PARDO D. SANCHEZ-MATA P. CANTÓ 《Botanical journal of the Linnean Society. Linnean Society of London》1998,128(4):423-434
Karyological information about Iberian Genista species is limited because of their wide geographical distribution. It is a major factor in the understanding of a genus whose genetic evolution is mostly related to aneuploidy and euploidy. The chromosome numbers of the following taxa have been counted: G. carpetana subsp. carpetana (n = 20), G. cinerascens (n = 12), G. micrantha (n = 18), G. mugronensis subsp. rigidissima (n = 18), G. ramosissima (2n = 48) and G. tinctoria (n = 24). The previously-assumed uniformity of chromosome number (n = 24) for all the subspecies of G. cinerea is supported here by data from subspp. murcica and speciosa. In G. florida, a new chromosome number, n = 23, has been found for both subspecies (florida and polygaliphylla). A discussion of the discrepancies between these data and previous ones is included. A new level of ploidy has been found in G. tuurnefortii subsp. tournefortii (n = 32). The data stress the necessity of obtaining chromosomal information from a number of plants of a taxon before its characteristic number is clear, and indicate that more chromosomal data will help the understanding of the cytological diversity within taxa in Genista. 相似文献
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A general review is presented of the Carboniferous floral records in the Iberian Peninsula in the context of the geological history and distribution of the different basins. Mississippian floras are found in Sierra Morena, where major strike-slip faults brought in terranes of diverse provenance. Lower Pennsylvanian floras are represented in the Peñarroya-Belmez-Espiel (Córdoba) and Villanueva del Río y Minas (Sevilla) coalfields of SW Spain (also strike-slip controlled), at La Camocha, near Gijón (Asturias), and in other parts of northern Spain. Middle Pennsylvanian is represented near Oporto, but more completely in the Central Asturian Coalfield, as well as other, more limited localities in NW Spain and the Pyrenees. Upper Pennsylvanian (Stephanian Stage-Cantabrian to Stephanian B substages) floras are splendidly represented in NW Spain. Uppermost Pennsylvanian (Stephanian C-Autunian) floras are present in the strike-slip controlled Douro and Buçaco basins of North Portugal, the Pyrenees, Central Spain (Ciudad Real, Guadalajara, Zaragoza), and SW Spain (Guadalcanal and Valdeviar in Sevilla province).A complete succession of megafloral zones is presented. This includes a new Annularia spicata Zone at the top of the Pennsylvanian (equivalent to middle to upper Autunian which has been often attributed to the Lower Permian). The information is summarised in charts compiled from a selection of the most significant species. A number of floral elements are illustrated including the zonal indices. Brief taxonomic comments are provided in the Appendix. 相似文献
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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
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SONIA BERNARDOS FRANCISCO AMICH FRANCISCA GALLEGO 《Botanical journal of the Linnean Society. Linnean Society of London》2003,142(4):395-406
Karyological information on Iberian Ophrys species is very limited. This paper provides the haploid and diploid chromosome numbers of 11 taxa of sect. Pseudophrys and sect. Ophrys , both of which are well represented in the Iberian Peninsula, and two taxa from Tunisia. The first data on chromosome numbers for O. vasconica (2 n = 72, 74), O. ficalhoana (2 n = 36), O. picta (2 n = 36), O. sphegifera ( n = 18, 2 n = 36, 38) and O. passionis (2 n = 36) are also presented, confirming the stability of the chromosome number in Ophrys . In addition, populations of the group O. omegaifera ( O. dyris and O. vasconica ), together with tetraploidy, pentaploidy and the existence of aneuploid phenomena, are reported for the first time in Iberia. The basic diploid number is always 2 n = 36. The karyotypes of several species were analysed. Evolutionary trends in Ophrys chromosomes are discussed. Taxonomic and phytogeographical details are provided on several species or groups of species from Iberia. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003 , 142 , 395−406. 相似文献
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FRANCISCO AMICH JUAN A. DEVESA SONIA BERNARDOS 《Botanical journal of the Linnean Society. Linnean Society of London》2004,144(3):351-364
A revision of the three endemic Iberian species of Succisella G. Beck ( S. carvalhoana , S. microcephala and S. andreae-molinae ), based on herbarium studies, SEM photographs and field observations, is presented utilizing morphological, palynological, karyological, biogeographical and ecological characters. The distribution of the species in the Iberian Peninsula is shown in a grid map. Full synonymy is given for all taxa. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 351–364. 相似文献
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Aquatic and riparian ecosystems are known to be highly vulnerable to invasive alien species (IAS), especially when subjected to human-induced disturbances. In the last three decades, we have witnessed a growing increase in plant invasions in Portugal and Spain (Iberian Peninsula, south-western Europe), with very detrimental economic, social and ecological effects. Some of these species, such as the giant reed (Arundo donax L.) and the water hyacinth (Eichhornia crassipes (Mart.) Solms-Laub.), number among the world's worst weeds. We present an appraisal of this invasive alien river flora and the most problematic aquatic weeds. We review various aspects of invasion ecology, including spatial and temporal patterns of invasion, species invasiveness, species traits of invasive weeds, and relationships between human disturbance in rivers and surrounding areas and invasibility, and contextualize them in overall state-of-the-art terms. We also acknowledge the use of IAS as bioindicators of the ecological quality of rivers, wetlands and riparian zones. Remote-sensing tools and Geographic Information Systems for detecting and monitoring IAS in Iberian rivers are presented. 相似文献
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The Iberian Peninsula represents a hot spot of cyphophthalmid (mite harvestman) disparity, with four of the eight genera currently recognized in the family Sironidae represented in the region – a generic diversity and morphological disparity not found in any other region of the World so far. From these, two genera (Iberosiro and Odontosiro) are monotypic, and are restricted to the western side of the peninsula. Parasiro is restricted to the north‐east region, from the Catalonian Coastal Ranges and both sides of the Eastern Pyrenees, in areas where the annual rainfall surpasses 1000 mm, and mostly restricted to areas with Paleozoic and Variscan rocks, with other species of the genus extending to Corsica, Sardinia, and the Italian Peninsula. A second species of the genus Paramiopsalis, Paramiopsalis eduardoi sp. nov. from Fragas do Eume, is described here along with a re‐diagnosis of the genus. Paramiopsalis species, together with Odontosiro, inhabit the north‐west corner of the Iberian Peninsula, an area with some of the highest recorded annual rainfall, and with Paleozoic rocks from the Iberian Massif or Variscan granitoid rocks. A phylogenetic analysis of the members of the family Sironidae using four molecular markers, despite not including all of the Iberian genera, clearly shows the non‐monophyly of the Iberian Cyphophthalmi, indicating that the Iberian Peninsula is home to multiple ancient lineages of mite harvestmen. The two Paramiopsalis species form a sister clade to the Balkan genus Cyphophthalmus, whereas Parasiro constitutes the first lineage of the sironids represented. 相似文献
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Y. VELÁSQUEZ C. MAGAÑA A. MARTÍNEZ‐SÁNCHEZ S. ROJO 《Medical and veterinary entomology》2010,24(3):293-308
A revision of the species and families of sarcosaprophagous flies (Diptera: Calliphoridae, Sarcophagidae, Muscidae, Fanniidae, Drosophilidae, Phoridae, Piophilidae and Stratiomyidae) suitable for forensic purposes in the Iberian Peninsula is presented. Morphological characteristics that allow the accurate identification of third instars of the species present in the Iberian Peninsula are described and presented in the form of a diagnostic key. For larval Calliphoridae, characteristics such as the spines of the body segments were useful for the genus Calliphora whereas features of the anal segment and the cephalopharyngeal skeleton were useful for larvae of Lucilia. Identification of three Chrysominae species present in the Iberian Peninsula is included. For larval Sarcophagidae, characters such as the arrangement and shape of spiracular openings, structures of the anal segment and the cephalopharyngeal skeleton were used for the first time. A new record of Sarcophaga cultellata Pandellé, from a human corpse, is also included as well as recent incursions into the European cadaveric entomofauna such as Synthesiomyia nudiseta (van der Wulp) and Hermetia illucens (Linnaeus). This work provides useful new information that could be applied to forensic investigations in the Iberian Peninsula and in southern Europe. 相似文献
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A study of morphological variation patterns in three Iberian Fucus species has been carried out. Data on 36 features from 113 specimens have been studied by numerical methods (PCA, discriminant analysis and ANOVA).The PCA ordination displayed a continuous trend of variation in the following Fucus species: F. ceranoides, F. vesiculosus and F. spiralis. However, no obvious morphological discontinuities have been observed. In addition, three varieties of F. spiralis and five of F. vesiculosus have been identified.At the varietal level discriminant functions could be used for identifying 93–100% of the individuals within F. vesiculosus and 72–91% of F. spiralis.The most discriminating diagnostic character appeared to be the midrib size, as detected by ANOVA procedures.Some qualitative characters, such as presence of vesicles, dioecious-monoecious character and receptacle edge shape, frond and receptacle shape, have been also important for discriminating specific and infraspecific taxa.A nomenclatural discussion of varietal taxa is also included. 相似文献
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The present study suggests that the Santa Eufemia-Ereñozar karst unit in northern Iberian Peninsula is a biodiversity hotspot for groundwater oligochaetes, due to (1) the presence of a high number of stygobiotic species (corresponding to 18% of the total stygobionts known in southern Europe); (2) the comparatively high number of oligochaete species collected (corresponding to 35% of the total epigean and hypogean oligochaete species in the region); and (3) the presence of 5 species endemic to the region. A list of the oligochaete taxa found in the karst unit is presented and a conservation ranking of the cavities in the karst is proposed based on the application of four biodiversity indices (Species richness, Rarity, Vulnerability and Complementarity) to the oligochaete taxa. Vulnerability was evaluated for the first time for groundwater oligochaete taxa and it provided a useful tool to assess the protection status of oligochaetes in karstic systems. Groundwater conservation management strategies could incorporate biodiversity data from the present study. 相似文献
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MANUEL B. CRESPO 《Botanical journal of the Linnean Society. Linnean Society of London》1992,109(3):369-376
CRESPO, MB., 1992. A new species of Vella L. (Brassicaceae) from the south-eastern part of the Iberian Peninsula . Vella lucenlina is described from the coastal, low, dry areas of Alicante Province (south-eastern Spain). This plant is a spineless shrub, woody at the base, with narrowly linear, entire leaves, and an acute tongue-shaped stylar part of the fruit. Affinities and differences with the other taxa in the genus are discussed, and ecological data and conservation proposals are reported. 相似文献
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The Lesser Rhea (Pterocnemia-Rhea-pennata pennata) has a complex reproductive system that combines polygyny with sequential polyandry, in which males build the nest, fully
incubate the eggs and care for the young. As occurs with the Greater Rhea (Rhea americana), Lesser Rhea females sporadically lay eggs outside the nest (‘orphan’ eggs), which are not incubated and thus fail to hatch.
We have examined the orphan eggs of Lesser Rhea over two separate breeding seasons to determine their abundance and fertility
status. During 2004 and 2005, weekly ground searches for orphan eggs were conducted in a wild population of Lesser Rhea in
northwestern Patagonia, Argentina. During these searches the total number of nests, eggs in each nest and orphan eggs laid
outside the nests was recorded. Orphan eggs represented approximately 7% of the total eggs laid in a breeding season. Six
fresh orphan eggs were artificially incubated, four of them being fertile. Orphan eggs seemed to have two origins: some were
laid near deserted nests in the early to mid-reproductive season; others were probably laid by first-time breeders and were
found later in the reproductive season. Given the near-threatened status of the Lesser Rhea, harvesting and artificial incubation
of orphan eggs, which otherwise would be unproductive, may contribute significantly to the conservation of this species, i.e.,
‘recovered’ birds could be used for reintroduction or reinforcement of wild Lesser Rhea populations. 相似文献
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M. W. Schwartz C. A. Brigham J. D. Hoeksema K. G. Lyons M. H. Mills P.J. van Mantgem 《Oecologia》2000,122(3):297-305
We evaluate the empirical and theoretical support for the hypothesis that a large proportion of native species richness is
required to maximize ecosystem stability and sustain function. This assessment is important for conservation strategies because
sustenance of ecosystem functions has been used as an argument for the conservation of species. If ecosystem functions are
sustained at relatively low species richness, then arguing for the conservation of ecosystem function, no matter how important
in its own right, does not strongly argue for the conservation of species. Additionally, for this to be a strong conservation
argument the link between species diversity and ecosystem functions of value to the human community must be clear. We review
the empirical literature to quantify the support for two hypotheses: (1) species richness is positively correlated with ecosystem
function, and (2) ecosystem functions do not saturate at low species richness relative to the observed or experimental diversity.
Few empirical studies demonstrate improved function at high levels of species richness. Second, we analyze recent theoretical
models in order to estimate the level of species richness required to maintain ecosystem function. Again we find that, within
a single trophic level, most mathematical models predict saturation of ecosystem function at a low proportion of local species
richness. We also analyze a theoretical model linking species number to ecosystem stability. This model predicts that species
richness beyond the first few species does not typically increase ecosystem stability. One reason that high species richness
may not contribute significantly to function or stability is that most communities are characterized by strong dominance such
that a few species provide the vast majority of the community biomass. Rapid turnover of species may rescue the concept that
diversity leads to maximum function and stability. The role of turnover in ecosystem function and stability has not been investigated.
Despite the recent rush to embrace the linkage between biodiversity and ecosystem function, we find little support for the
hypothesis that there is a strong dependence of ecosystem function on the full complement of diversity within sites. Given
this observation, the conservation community should take a cautious view of endorsing this linkage as a model to promote conservation
goals.
Received: 2 September 1999 / Accepted: 26 October 1999 相似文献
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P. CUBAS H. TAHIRI C. PARDO 《Botanical journal of the Linnean Society. Linnean Society of London》2001,135(1):43-50
Karyological information on Cytisus species indicates at least two chromosome numbers for most of the taxa. This instability is, a striking karyological feature of Cytisus . Chromosome numbers of taxa in Sect. Spartopsis and Sect. Alburnoides, both well represented in Morocco and the Iberian Peninsula, are presented here. We provide the first data on chromosome numbers for the Moroccan taxa: C. grandiflorus subsp. barbarus , and subsp. haplophyllus (n = 23, 2 n = 46) , C. maurus (2 n = 48), C. megalanthus ( n = 23), C. arboreus subsp. arboreus , subsp. baeticus , and subsp. catalaunicus (2 n = 50), C. valdesii ( n = 23 ). New populations from the Iberian Peninsula have been counted: C. grandiflorus subsp. grandiflorus (2 n = 46), C. scoparius subsp. scoparius ( n = 23) , C. striatus subsp. eriocarpus ( n = 23, 2 n = 46), C. multiflorus (n = 23), C. oromediterraneus ( n = 23, 24). Our data confirm the instability of the chromosome number in Cytisus . The presence of B chromosomes in C. valdesii and C. megalanthus , as well in other species, is discussed in relation to this instability and previous data. We suggest that instability of the chromosome number within a taxon, and even in the same population, may be related to the breakage of A chromosomes and the appearance of B chromosomes. 相似文献
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Torres J.A. Valle F. Pinto C. García-Fuentes A. Salazar C. Cano E. 《Plant Ecology》2002,160(2):207-223
Arbutus unedo L. communities in the southern part of the Iberian Peninsula (Spain and Portugal) were studied, highlighting the differences regarding their floristic composition, biological diversity and plant dynamics according to the dominant geological substratum. Firstly, this type of formation on the little-known decarbonated calcareous substrata was analysed using classification techniques. Later, they were compared to the remaining phytocoenoses in the southern part of the Iberian Peninsula using an ordination analysis. As a result, a new suballiance is proposed together with two plant associations, which will enable us to characterize the strawberry tree groves growing on carbonated substrata and those already proposed for siliceous substrata are confirmed. 相似文献
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Some avian Harpirhynchidae mites live under the skin and develop cutaneous cysts. Despite the obvious lesions that these parasites can produce, little is currently known about the behavioural disturbances that cyst-forming mites may cause in infected wild birds. We report an infection by Harpirhynchidae mites in a hawfinch (Coccothraustes coccothraustes) in southeast Spain. The bird was easily captured due to its inability to fly. During clinical examination it was found to have multiple severe traumatic injuries, possibly due to a blow or a fall, as result of which the bird was euthanized. At necropsy, the hawfinch was found to be in good body condition. Two yellowish and friable mite-filled cysts were detected in the subalar region of both wings. Mites were morphologically identified as Harpirhynchus nidulans, and histological analysis of the cystic lesions was also performed. This is the first time that the occurrence of a hawfinch infected by H. nidulans in the Iberian Peninsula has been reported. 相似文献