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1.
Valle LG  Santamaria S 《Mycologia》2004,96(3):682-701
A study of larval Diptera (Chironomidae, Culicidae and Simuliidae) from Spain has been carried out to fulfill a catalogue of species of the genus Smittium (Harpellales: Legeriomycetaceae) present within these hosts. Among the reported taxa, eight are new species: Smittium brevisporum, S. bulbosporo-phorus, S. gracilis, S. hecatei, S. heterosporum, S. inex-pectans, S. prostratum and S. pseudodimorphum. We also report six previously described species, which are new for the Iberian Peninsula: S. alpinum, S. dipterorum, S. megazygosporum, S. pusillum, S. typhellum and S. fecundum. Three other species (S. simulii, S. culicis and S. culisetae) previously were reported from Spain. In two of them (S. fecundum and S. culicis), we describe for the first time the presence of zygospores. Some of the included species have been artificially cultured as well as ultrastructurally studied using scanning electron microscopy (SEM), with the purpose of observing the surface of both trichospores and the trichospore collar and the morphology of the trichospore appendage.  相似文献   

2.
The temporal variation of the gastropod fauna inhabiting sandy sediments of the Ensenada de Baiona (Galicia, Spain) was studied at three subtidal sites from February 1996 to February 1997 by means of quantitative sampling. A total of 5,463 individuals representing 51 gastropod species and 22 families were found. The family Pyramidellidae was the most diverse in number of species (11 species), followed by Rissoidae and Trochidae (4 species each). The dogwhelk, Nassarius reticulatus, and the rissoid snail, Rissoa parva, were the numerically dominant species at the three studied sites; those and other abundant species showed their greatest densities by the end of summer and the beginning of autumn. In general, univariate measures of the assemblage (number of species, abundance, diversity and evenness) showed variations through time; greater values were recorded between summer and autumn depending on the site. Multivariate analyses done on abundance data showed certain seasonality in the evolution of the assemblage as expected for shallow subtidal sandy sediments at temperate latitudes; those seasonal changes were mostly related to variations in abundance of numerically dominant species. Although the measured sedimentary variables did not show significant correlations with faunal univariate parameters, sediment heterogeneity due to the presence of mats of Zostera marina L. and shells of dead bivalves might explain the differences in composition of the gastropod assemblage among sampling sites.  相似文献   

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The two subspecies of Ulex europaeus L. (subsp. europaeus and subsp. latebracteatus) are easily differentiated by the shape and size of their bracteoles, and by their chromosome number. However, in the north-west of the Iberian Peninsula, the areas of both subspecies are not clearly delimited, the shape of the bracteoles is intermediate and the width is close to the diagnostic limit. Thus, allocation of some specimens to either subspecies is diffcult. Recendy, a controversy has arisen concerning the intrapopulational uniformity of the chromosome number in U. europaeus from west France and north Spain, and the usefulness of ploidy level and chromosome number as clear-cut indicators of the two subspecies. Thus, the merits of recognizing the subspecies as independent are re-analysed here. Our results for north-west Spain show that the chromosome number is uniform and stable within populations and is clearly related to the morphological characters. Correlation and discriminant analyses show that bracteoles and stomata sizes are highly correlated and are good predictors of ploidy level. Furthermore, the results support the maintenance of two subspecies in U. europaeus , which can be delimited by a combination of morphological characters, chromosome number and geographical distribution.  相似文献   

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The taxonomic status of the freshwater mollusc fauna of the Iberian Peninsula it is reasonably well known, but, unlike other benthic macroinvertebrate, its distribution and ecology has been poorly studied. In this article, I study the relationships between environmental characteristics and distribution and community structure of freshwater molluscs along climatic, hydrological, physicochemical, and heterogeneity gradients in the southwestern Iberian Peninsula. Ninety-four sampling points were analysed, in which, in addition to habitat features, the presence/absence and abundance of species were evaluated. The environmental gradients were measured by use of principal-components analysis (PAC), which orders the variables along two gradients: headwaters-mouth gradient (PC1) and water availability (PC2). According to canonical correspondence analysis (CCA), the main environmental factors related to species distribution and community structure were conductivity, permanency, channel width, turbidity, slope, and distance to the main river axis. The relationship between biodiversity (measured as species richness and the Shannon–Weiner diversity index), the ratio of the number of introduced species to the total number of species (zoogeographic integrity coefficient), and environmental variables was best explained by a regression model incorporating, basically, the permanence of water in streams as the variable that accounted for most of the variance. This study demonstrates that the distribution of freshwater molluscs along a Mediterranean gradient highly stressed by drought depends, mainly, on the hydrological stability and environmental conditions of the headwaters and estuarine sites.  相似文献   

7.
A karyological study of 15 taxa ofScorzonera L. from the Iberian Peninsula has been made. The chromosome numbers found inS. hispanica var.pinnatifida, S. baetica, S. reverchonii, S. angustifolia, S. laciniata var.calcitrapifolia and var.subulata (2n = 14) are new. Diploid cytotypes with 2n = 14 and 2n = 12 prevail, andS. hispanica var.crispatula is the only taxon which exhibits autopolyploidy (2n = 14, 28). x = 7 is considered to be the base chromosome number within the genus, with x = 6 being derived from it by translocation. This and detailed karyotype analyses allow to group the Iberian Peninsula species ofScorzonera into three groups.  相似文献   

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Petrocoptis grandiflora Rothm. is a species endemic to the Iberian Peninsula with restricted distribution. We studied various aspects of its pollination ecology, nectar characteristics and standing crop, pollinators and nectar-robbers, and the effects of nectar robbing and supplementary pollination on fruit set. The nectar is moderately rich in saccharose (saccharose/hexose ratio 0.54), and is largely consumed by long-tongued bees (Anthophoridae). The incidence of nectar robbing by Xylocopa violncea differed between the four plant populations studied, and it had significant effects on fruit set when the population was simultaneously considered. Supplementary pollination did not improve fruit set significantly.  相似文献   

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The aim of this work is to provide a first approach to the evolution of Iberia's vegetation during the Cenozoic (with the exclusion of the Quaternary). The Palaeogene was floristically defined by Palaeotropical elements forming tropical/subtropical rainforests, mangrove swamps, edaphically-mediated laurophyllous forests and leguminous-sclerophyllous communities. During the Miocene, Iberian landscapes were drastically modified due to geographic and climatic changes (mainly cooling and aridification) changes. Open, steppe-like environments developed towards the interior of the peninsula and Arctotertiary elements invaded mountainous and riparian ecosystems, coexisting with or becoming part of evergreen, broadleaved forests of Palaeotropical species. From the Late Miocene onwards these forests suffered changes due to the extinction of taxa, the impact of environmental change on the survivors, and the perturbations caused by the arrival of further Arctotertiary elements. However, several Palaeotropical taxa overcame the environmental and climatic changes of the Miocene and Pliocene to form a part of the modern flora of the Iberian Peninsula.  相似文献   

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Although it is generally accepted that the tribe Genisteae has rather homogeneous pollen, we have found considerable variation in pollen size and morphology in Cytisus and related genera (Argyrocytisus and Chamaecytisus), which match taxonomic groups defined on morphological grounds. The results of Principal Component Analysis of pollen characteristics show the following: Cytisus Sect. Alburnoides is well-delimited, with the smallest pollen grains and the simplest pattern in the tectum, fossulate-perforate to perforate; No separation of C. villosus (Sect. Cytisus) from Sect. Alburnoides is observed; Cytisus Sect. Spartopsis, with the largest pollen grains and reticulate to reticulate-fossulate ornamentation, forms an isolated group; C. fontanesii (Sect. Heterocytisus) stands apart from other Cytisus species by its homogeneous ornamentation and the perforate instead of psilate-punctate margo. Thus, the pollen data supports its transfer to the separated genus Chronanthos; Pollen ornamentation and morphology also support the separation of Argyrocytisus battandieri and Chamaecytisus mollis from Cytisus.  相似文献   

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Achenes of all the Tragopogon species from the Iberian Peninsula were examined by means of scanning-electron microscopy and stereomicroscopy. The achenes of the eight species are described, illustrated and compared. The results are contrasted with the systematics of this genus. The isolated position of T. lamottei with regard to the other seven species is noted. A key is provided to enable the different species to be distinguished.  相似文献   

16.
《Comptes Rendus Palevol》2016,15(5):489-500
A new stem dugongid species, Prototherium ausetanum sp. nov. (Dugongidae, Halitheriinae), is described based on a cranium from the middle Eocene of Mas Vilageliu (Tona, NE Iberian Peninsula). The new species displays a combination of features that enables its distinction from other halitheriines, including Prototherium veronense (type species of the genus), Prototherium? intermedium (which likely belongs to a different genus), and Prototherium? montserratense (here considered a nomen dubium), as well as Eotheroides spp. In overall morphology (e.g., dolichocephaly) the new species more closely resembles species previously included in Prototherium. However, a cladistic analysis based on craniodental features recovers the new species as the sister taxon of Eotheroides aegyptiacum (type species of this genus), further constituting a polytomy with P. veronense, Eotheroides lambondrano and the remaining Halitheriinae. Our analysis further indicates that P.? intermedium is more derived than other species of Prototherium, but it does not conclusively resolve the phylogenetic relationships between the included species of Prototherium and Eotheroides. A deeper taxonomic revision of these two genera would be required in order to better resolve the phylogeny of early dugongids.  相似文献   

17.
We studied the reproductive biology ofPrunus spinosa andPrunus mahaleb (Prunoideae, Rosaceae) in the northwest Iberian Peninsula. The two species flowered at the same time (peaking on March 9 and 11, respectively in 1990) but differ significantly in their fruit maturation times. Nectar volume peaked in the early morning in both species, and was ten times greater inP. spinosa than inP. mahaleb. Neither species shows apomixis, nor does fruit-set occur if pollinators are excluded. In both species self-pollination resulted in fewer fruits than open pollination. The principal pollinators belong to theApidae family (79% and 63% of visits toP. spinosa andP. mahaleb, respectively). Results are compared with those for other rosaceous plants with fleshy fruits.  相似文献   

18.
A study of polyclad fauna of the Atlantic coast of the Iberian Peninsula was carried out from 2010 to 2013. The paper reports nine new records belonging to three Cotylean families: the family Euryleptidae Lang, 1884, Pseudocerotidae Lang, 1884 and the family Prosthiostomidae Lang, 1884, and describes one new species, Euryleptodes galikiassp. n.  相似文献   

19.
The soft-bottom caprellids of the Iberian Peninsula are revised. Nineteen species have been reported so far, 42 % being endemic to the Mediterranean Sea. The lateral view of all of them is provided, together with an illustrated key for all the species. An ecological study was also conducted during 2007–2010 along the Andalusian coast to explore the relationships of caprellids with abiotic data. A total of 90 stations (0–40 m deep) were sampled and 40 contained caprellids. Along the Atlantic, caprellids were present in only 20 % of the stations, while along the Mediterranean coast, caprellids were present in the 75 % of the sampling sites. Furthermore, the abundance of caprellids was also higher in the Mediterranean coast. The dominant species was Pseudolirius kroyeri (present in 24 stations and showing the highest abundances with 1,780 ind/m2), followed by Phtisica marina (22 stations) and Pariambus typicus (11 stations). According to CCA and BIO-ENV, sediment type, P, pH and oxygen were the parameters that better explained the distribution of caprellids. Although the three dominant species were found in all types of sediment, the univariate approach showed that P. kroyeri was significantly more abundant in fine sediments (silt–clay and very fine sands) than in gross sediments (coarse and very coarse sands). The majority of studies dealing with caprellids from the Iberian Peninsula have been focused on shallow waters and further efforts are needed to explore biodiversity of deeper areas.  相似文献   

20.
Barrasa JM  Rico VJ 《Mycologia》2003,95(4):700-713
A taxonomic study of the species with nutant, pleurotoid and cyphelloid basidiomata of the genus Arrhenia in the Iberian Peninsula is presented. This study is based on the examination of recent specimens collected in the field and from dried herbarium collections. Five species and one variety of this genus are recognized on the basis of morphological and ecological features: Arrhenia acerosa var. acerosa, A. acerosa var. tenella, A. auriscalpium, A. lobata, A. retiruga and A. spathulata. Arrhenia auriscalpium is new to Spain, where it is not restricted to alpine zones of the Eurosiberian region and is more common in the Mediterranean region than previously reported. In contrast, A. acerosa var. tenella currently is known from the Eurosiberian subalpine belt and represents the first report to the Iberian Peninsula, and A. retiruga is known only from the mesomediterranean to supramediterranean belts of the Mediterranean region. Arrhenia acerosa var. acerosa, A. lobata and A. spathulata are widespread in both the Eurosiberian and the Mediterranean regions. Non-Iberian materials of A. acerosa var. tenella and A. spathulata also were studied for comparison. Cyphella cochlearis var. subsessilis, Dictyolus lagunae, Leptoglossum muscigenum var. azonum and Pleurotellus acerosus var. tenellus are lectotypified. Cyphella cochlearis var. subssesilis, Dictyolus lagunae and Leptoglossum muscigenum var. azonum are synonymized with Arrhenia spathulata, and Cyphella cochlearis var. auriformis is placed in synonymy with A. auriscalpium. These taxa are illustrated, described and discussed, based on Iberian material with emphasis on features of the basidioma, pigment of the pileipellis, presence or absence of clamps and shape and size of the basidiospores. A diagnostic key also is given.  相似文献   

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