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1.
Studies of type specimens and other specimens of Menegazzia subsimilis and M. dissecta have shown that they are referable to the same taxon. Thus, M. dissecta is reduced to synonymy with M. subsimilis, which is characterized by lacerate soralia protruding from lobe apices or vertical lobules (protuberances), small perforations and the presence of the stictic acid complex in the medulla. It has 2-spored asci. The synonymy implies that M. subsimilis has a much wider distribution range than previously known. It is reported here from Oceania (Hawaii, Solomon Islands), Asia (Japan, Papua New Guinea, Russia), Europe (Austria, Germany, Portugal), South America (Ecuador, Peru), the Caribbean (Dominican Republic, Jamaica) and North America (Canada, USA).  相似文献   

2.
Dexosarcophaga tupinamba n. sp. is described based on male specimens from the Brazilian states of Pará and Maranhão; Dexosarcophaga bermudezi Silva & Mello-Patiu is newly recorded from Pará and South America; and Dexosarcophaga avispaensis Mello is newly recorded from Pará (new to Brazil). The Brazilian species Dexosarcophaga limitata (Lopes) and Dexosarcophaga pusilla (Lopes) are both recorded from Pará, which are new records from the Brazilian Amazon, Dexosarcophaga aurifacies (Lopes) is newly recorded from the state of Alagoas and Dexosarcophaga carvalhoi (Lopes) is newly recorded from the states of Mato Grosso, Maranhão, and Pará. A key to the identification of males of the subgenus Bezzisca is provided.  相似文献   

3.
The native solitary ascidian Corella eumyota Traustedt, 1882) is commonly found in the Southern Hemisphere in the cold-temperate waters of the Subantarctic and Antarctic regions. Its recent spread into the Northern Hemisphere throughout the NE Atlantic gave the species the status of invasive. Together with its widespread distribution, reports on its wide variability (several distinct morphological characters, genetic discontinuities and also possible misidentifications) cast doubt on the taxonomic status of different populations of this species. This work, based on the observation, quantification and analysis of specific morphological characters in specimens collected at five different localities of South America and Antarctica, strongly indicates that there are two different species: C. eumyota from South America and Corella antarctica Sluiter, 1905) from Antarctica, which has been till now considered a junior synonym of the former. The species clearly differ in the arrangement of the gonadal ducts, the size of the larvae and the shape of the anus, among other characters. Morphological variation displays a defined, discrete grouping supporting a clear differentiation into two species. This result shows the need for careful inspection of specimens to avoid wrong interpretations in a context of changes of marine biota due to biological invasions.  相似文献   

4.
5.
A review of palm remains recorded at archaeological sites throughout the New World is presented. Remains have been found at 130 sites from the southern United States to southern Uruguay. They are of four kinds: carbonized or dry endocarps or seeds, phytoliths, pollen, and implements. Twenty-nine genera and at least 50 species of palms (i.e., about 9% of all American species) have been recorded. The oldest record dates back to 14,700b.p. for carbonized endocarp fragments of an unidentified palm in Rondônia, Brazil. The use of palms, as recorded from remains, was particularly widespread after 9000b.p. The predominant remains are endocarps ofAcrocomia, Attalea s.l.,Astrocaryum, Bactris, Syagrus, Elaeis, andOenocarpus, all of which are important sources of edible oils or edible fruits and are still widely used by aboriginal peoples. The review supports the hypothesis that human groups have played an important role in the dispersal of some palm species in the neotropics. Humanaided dispersal ofAcrocomia aculeata from South America into Central America, and ofOenocarpus bataua from northwestern Amazonia to other areas, is postulated. Archaeological remains support the hypothesis that pejibaye (Bactris gasipaes) was domesticated in the inter-Andean valleys or on the adjacent Pacific lowlands of Colombia and later introduced into the Amazon Basin.  相似文献   

6.
Based on material collected from Pseudemys nelsoni (Reptilia: Chelonia: Emydidae) during a parasite survey of the herpetofauna around Gainesville, Florida, USA, Polystomoides nelsoni sp. n. is described as a new polystome species. This parasite was found in the oral and pharyngeal region of the host. In a sample of nine Pseudemys nelsoni, three specimens were found to release polystome eggs. One turtle was euthanized and dissected and found to be infected in the oral region with 19 specimens belonging to an as-yet-unknown Polystomoides. This is only the fifth Polystomoides recorded from the Nearctic realm. This species is distinguished from known species by a combination of characteristics including marginal hooklet morphology, body length and haptor dimensions.  相似文献   

7.
The chytrid fungus, Batrachochytrium dendrobatidis (Bd), has been identified as a major cause of the recent worldwide amphibian decline. Numerous species in North America alone are under threat or have succumbed to Bd-driven population extinctions. The American bullfrog (Lithobates catesbeianus) has been reported as a tolerant carrier of Bd. In this report, we used a qPCR assay to test 120 archived American bullfrog specimens collected between 1924 and 2007 in California, USA and Baja California, Mexico. The overall prevalence of Bd infection in this archived population of L. catesbeianus was 19.2%. The earliest positive specimen was collected in Sacramento County, California, USA in 1928 and is to date the earliest positive archived Bd specimen reported globally. These data demonstrate that Bd-infected wild amphibians have been present in California longer than previously known.  相似文献   

8.
Common ragweed (Ambrosia artemisiifolia) is an invasive and highly allergenic plant species, on which two species, Plasmopara halstedii and Plasmopara angustiterminalis, have been recognized to cause downy mildew disease. In this study, morphological and molecular patterns of seven Plasmopara specimens collected from A. artemisiifolia in Canada, Hungary, and USA were compared with those of P. halstedii and P. angustiterminalis from Helianthus and Xanthium, respectively. Analyses of partial sequences of three genes, namely those for the large subunit (28S) of rDNA, cytochrome c oxidase subunit II (COX2), and NADH dehydrogenase subunit I (ND1) of mtDNA, were carried out to examine the phylogenetic relationships among these specimens using both Bayesian and maximum parsimony methods. All the phylogenetic analyses revealed that the downy mildew pathogens infecting A. artemisiifolia in Hungary and North America clearly represent a lineage distinct from other Plasmopara taxa investigated. The shape of sporangia and the width of trunks and branches also allowed the separation of the specimens parasitic to A. artemisiifolia from P. halstedii on Helianthus annuus and P. angustiterminalis on Xanthium strumarium. Surprisingly, the Hungarian and the Canadian specimens were more closely related to each other than to those from the USA based on COX2 and ND1 mtDNA data, although the D1/D2/D3 sequences of 28S rDNA were identical in all these Plasmopara specimens. The regional distribution of the mtDNA haplotypes seen in this study suggests a transatlantic migration has occurred and would be interesting to follow up with a more detailed sampling. To investigate the diversity within P. halstedii sensu lato, infecting different host plant species, specimens from six asteraceous genera, Ambrosia, Flaveria, Helianthus, Siegesbeckia, Solidago, and Xanthium, were also included in molecular analyses. These represented six distinct lineages according to the host plant genera. These findings might serve as a basis for a taxonomical reassessment of the P. halstedii complex and also for the delimitation of several well-defined species within this complex.  相似文献   

9.
Snake fungal disease (SFD; ophidiomycosis), caused by the pathogen Ophidiomyces ophiodiicola (Oo), has been documented in wild snakes in North America and Eurasia, and is considered an emerging disease in the eastern United States of America. However, a lack of historical disease data has made it challenging to determine whether Oo is a recent arrival to the USA or whether SFD emergence is due to other factors. Here, we examined the genomes of 82 Oo strains to determine the pathogen’s history in the eastern USA. Oo strains from the USA formed a clade (Clade II) distinct from European strains (Clade I), and molecular dating indicated that these clades diverged too recently (approximately 2,000 years ago) for transcontinental dispersal of Oo to have occurred via natural snake movements across Beringia. A lack of nonrecombinant intermediates between clonal lineages in Clade II indicates that Oo has actually been introduced multiple times to North America from an unsampled source population, and molecular dating indicates that several of these introductions occurred within the last few hundred years. Molecular dating also indicated that the most common Clade II clonal lineages have expanded recently in the USA, with time of most recent common ancestor mean estimates ranging from 1985 to 2007 CE. The presence of Clade II in captive snakes worldwide demonstrates a potential mechanism of introduction and highlights that additional incursions are likely unless action is taken to reduce the risk of pathogen translocation and spillover into wild snake populations.

Snake fungal disease is an emerging disease in eastern North America, but the origins of the disease have been unclear. This study uses population genetic data to show that the fungus that causes the disease was introduced multiple times to North America over the last few hundred years.  相似文献   

10.
The Cuban fauna of the genus Berosus Leach, 1817 is reviewed based on newly collected material as well as historical and type specimens. Nine species are recognized, including three recorded from Cuba for the first time: Berosus infuscatus LeConte, 1855, Berosus interstitialis Knisch, 1924 (= Berosus stribalus Orchymont, 1946 syn. n.) and Berosus metalliceps Sharp, 1882. Only one of the nine Cuban species, Berosus chevrolati, remains endemic to Cuba, as two other species previously considered as endemic to Cuba are recorded from elsewhere: Berosus quadridens from Mexico and Central America and Berosus trilobus from the Dominican Republic. Notes on biology and Cuban distribution are provided for all nine species. Berosus quadridens Chevrolat, 1863, stat. restit. is removed from synonym with Berosus truncatipennis and considered a valid species.  相似文献   

11.
Grossi PC  Grossi EJ 《ZooKeys》2011,(75):21-28
A second species of Amblyodus Westwood, 1878, Amblyodus castroi sp. n., is described from the northern South America based on 12 specimens from Brazil and Peru (Amazonian subregion). The new species is here compared with the type species of the genus, Amblyodus taurus Westwood, 1878 and both species and their male genitalia are illustrated. Diagnostic characters for the genus are discussed, especially the metatibial teeth. A distribution map including the type species and the new species is provided. The genus Amblyodus is recorded for the first time from Peru and from Brazil states of Pará and Rondônia.  相似文献   

12.
The cestode Taenia arctos was found at necropsy in the small intestine of a grizzly (Ursus arctos horribilis) and a black bear (Ursus americanus) from Kananaskis Country in southwestern Alberta, Canada. The autolysis of the tapeworm specimens precluded detailed morphological characterization of the parasites but molecular analysis based on mitochondrial DNA cytochrome c oxidase subunit 1 gene confirmed their identity as T. arctos. This is the first report of T. arctos from definitive hosts in North America. Its detection in Canadian grizzly and black bears further supports the Holarctic distribution of this tapeworm species and its specificity for ursids as final hosts. Previously, T. arctos was unambiguously described at its adult stage in brown bears (Ursus arctos arctos) from Finland, and as larval stages in Eurasian elk (Alces alces) from Finland and moose (Alces americanus) from Alaska, USA. Given the morphological similarity between T. arctos and other Taenia species, the present study underlines the potential for misidentification of tapeworm taxa in previous parasitological reports from bears and moose across North America. The biogeographical history of both definitive and intermediate hosts in the Holarctic suggests an ancient interaction between U. arctos, Alces spp., and T. arctos, and a relatively recent host-switching event in U. americanus.  相似文献   

13.

Background

Basal sauropodomorphs, or ‘prosauropods,’ are a globally widespread paraphyletic assemblage of terrestrial herbivorous dinosaurs from the Late Triassic and Early Jurassic. In contrast to several other landmasses, the North American record of sauropodomorphs during this time interval remains sparse, limited to Early Jurassic occurrences of a single well-known taxon from eastern North America and several fragmentary specimens from western North America.

Methodology/Principal Findings

On the basis of a partial skeleton, we describe here a new basal sauropodomorph dinosaur from the Lower Jurassic Navajo Sandstone of southern Utah, Seitaad ruessi gen. et sp. nov. The partially articulated skeleton of Seitaad was likely buried post-mortem in the base of a collapsed dune foreset. The new taxon is characterized by a plate-like medial process of the scapula, a prominent proximal expansion of the deltopectoral crest of the humerus, a strongly inclined distal articular surface of the radius, and a proximally and laterally hypertrophied proximal metacarpal I.

Conclusions/Significance

Phylogenetic analysis recovers Seitaad as a derived basal sauropodomorph closely related to plateosaurid or massospondylid ‘prosauropods’ and its presence in western North America is not unexpected for a member of this highly cosmopolitan clade. This occurrence represents one of the most complete vertebrate body fossil specimens yet recovered from the Navajo Sandstone and one of the few basal sauropodomorph taxa currently known from North America.  相似文献   

14.
《Fungal biology》2014,118(9-10):755-763
Morchella species are edible fungi in high demand and therefore command high prices in world markets. Phenotypic-based identification at the species-level remains inadequate because of their complex life cycles, minor differences and plasticity of morphological characteristics between species, and the lack of agreement between scientific and common names. In Patagonia–Argentina, morels are associated with native forests of Austrocedrus chilensis (Cordilleran or Chilean cypress) and Nothofagus antarctica (ñire) and several exotic conifers that were introduced from western North America. Little is known about their taxonomy and phylogenetic relationships with other species in the genus. This work focused on the identification of collections of Morchella from Patagonia and their phylogenetic relationships with other species from the Northern Hemisphere. The comparison was made by analysis of DNA sequences obtained from four loci: the nuclear ribosomal internal transcribed spacer region (ITS) and the partial RNA polymerase I gene (RPB1) for the complete collection; and ITS, RPB1, RNA polymerase II gene (RPB2), and translation elongation factor (EF1-α) for the species-rich Elata Subclade. Analyses of individual and combined data sets revealed that Patagonian morels belong to the Elata Clade and comprised three strongly supported species-level lineages from both Patagonian native forest, and exotic trees introduced from western North America. One lineage was identified as Morchella frustrata phylogenetic species Mel-2, which is known from the USA and Canada. The second lineage, which appeared to be ‘fire-adapted’, was identified as Morchella septimelata phylogenetic species (Mel-7), which is also known from the USA. This species was collected from burned native forests mainly composed of A. chilensis and N. antarctica but also Pseudotsuga menziesii (Mirb.) Blanco, which is native to western North America. The phylogenetic analyses suggested that the third species from Patagonia was nested within the species-rich Elata Subclade and represents a new species-level lineage (informally designated Mel-37) within Elata Clade. The present collections from Patagonia constitute the southernmost latitude from which Morchella has been reported to date. The identification of two Argentine morels as North American taxa is therefore a remarkable biogeographic pattern. In view of the hypothesis that the Elata Clade originated in western North America, we speculate that at least two of the lineages colonized South America from North America via long distance dispersal, migration or, more likely, they were introduced with the exotic tree species that they were collected near.  相似文献   

15.
16.
The genus Newportia Gervais, 1847, includes some 60 nominal species distributed in the Caribbean islands and from Mexico to central South America. Modern keys to species and subspecies are available, greatly facilitating identification, but some species are based on few specimens and have incomplete documentation of taxonomically-informative characters. In order to explore genetic variability and evolutionary relationships within geographically-widespread morphospecies, specimens of Newportia (Newportia) stolli (Pocock, 1896) and Newportia (Newportia) divergens Chamberlin, 1922, two nominal species distinguished principally by differences in suture patterns on T1, were sequenced for mitochondrial 16S rRNA and cytochrome c oxidase subunit I (COI) genes from populations in southern Mexico, Guatemala, Honduras and Brazil. Newportia (Newportia) stolli is paraphyletic with respect to Newportia (Newportia) divergens within a clade from Guatemala, Honduras, and Chiapas (Mexico), most trees being consistent with a single loss of a connection between the anterior transverse suture on T1, whereas specimens of “Newportia (Newportia) stolli” from Brazil are not closely allied to those from the Mesomerican type area. The widespread morphospecies Newportia (Newportia) monticola Pocock, 1890, was sequenced for the same loci from populations in Costa Rica, Colombia and Brazil, finding that specimens from these areas do not unite as a monophyletic group. Samples of Newportia (Newportia) oreina Chamberlin, 1915, from different regions of Mexico form geographic clusters that resolve as each other’s closest relatives. These results suggest that some widespread species of Newportia may be taxa of convenience more so than natural groupings. In several cases geographic proximity fits the phylogeny better than taxonomy, suggesting that non-monophyletic species do not result from use of inappropriate molecular markers. Molecular identification is possible for specimens missing taxonomically informative morphological characters, notably damaged specimens that lack the ultimate leg pair, a protocol that may also apply to other taxonomically difficult genera that are prone to damage (such as Cryptops).  相似文献   

17.
This paper describes AnthWest, a large dataset that represents one of the outcomes of a comprehensive, broadly comparative study on the diversity, biology, biogeography, and evolution of Anthidium Fabricius in the Western Hemisphere. In this dataset a total of 22,648 adult occurrence records comprising 9657 unique events are documented for 92 species of Anthidium, including the invasive range of two introduced species from Eurasia, A. oblongatum (Illiger) and A. manicatum (Linnaeus). The geospatial coverage of the dataset extends from northern Canada and Alaska to southern Argentina, and from below sea level in Death Valley, California, USA, to 4700 m a.s.l. in Tucumán, Argentina. The majority of records in the dataset correspond to information recorded from individual specimens examined by the authors during this project and deposited in 60 biodiversity collections located in Africa, Europe, North and South America. A fraction (4.8%) of the occurrence records were taken from the literature, largely California records from a taxonomic treatment with some additional records for the two introduced species. The temporal scale of the dataset represents collection events recorded between 1886 and 2012. The dataset was developed employing SQL server 2008 r2. For each specimen, the following information is generally provided: scientific name including identification qualifier when species status is uncertain (e.g. “Questionable Determination” for 0.4% of the specimens), sex, temporal and geospatial details, coordinates, data collector, host plants, associated organisms, name of identifier, historic identification, historic identifier, taxonomic value (i.e., type specimen, voucher, etc.), and repository. For a small portion of the database records, bees associated with threatened or endangered plants (~ 0.08% of total records) as well as specimens collected as part of unpublished biological inventories (~17%), georeferencing is presented only to nearest degree and the information on floral host, locality, elevation, month, and day has been withheld. This database can potentially be used in species distribution and niche modeling studies, as well as in assessments of pollinator status and pollination services. For native pollinators, this large dataset of occurrence records is the first to be simultaneously developed during a species-level systematic study.  相似文献   

18.
The American bullfrog, Rana (Lithobates) catesbeianus, is endemic to eastern North America, but has been introduced to approximately 40 countries on four continents and is considered one of the hundred worst invasive alien species in the world. Here, we investigated the genetics of invasive bullfrogs in the Willamette Valley, Oregon, USA, where bullfrogs are widespread and abundant to determine: (1) the minimum number of bullfrog introductions; (2) the native source population(s); and (3) whether genetic variation is reduced compared to source populations. To answer these questions, we analyzed partial sequences of the mitochondrial cytochrome b gene for 251 bullfrogs from the Willamette Valley and the native range. We found that bullfrogs from the Mississippi River basin and Great Lakes region were introduced at least once to the Willamette Valley. Genetic variation measured as haplotype diversity (h) and nucleotide diversity (?? n ) was not significantly different between Willamette Valley and source populations. Our results were in contrast to a recent genetic analysis of invasive bullfrog populations in Europe, which found that genetic variation in European bullfrog populations was much lower than in source populations. European bullfrogs also originated from different source populations than Willamette Valley bullfrogs. The difference in genetic composition between Willamette Valley and European bullfrogs is likely due to differences in their invasion histories and may have implications for the potential of bullfrogs in these different regions to adapt and expand.  相似文献   

19.
In this paper new mitochondrial COI sequences of Common Barn Owl Tyto alba (Scopoli, 1769) and Short-eared Owl Asio flammeus (Pontoppidan, 1763) from southern Chile are reported and compared with sequences from other parts of the World. The intraspecific genetic divergence (mean p-distance) was 4.6 to 5.5% for the Common Barn Owl in comparison with specimens from northern Europe and Australasia and 3.1% for the Short-eared Owl with respect to samples from north America, northern Europe and northern Asia. Phylogenetic analyses revealed three distinctive groups for the Common Barn Owl: (i) South America (Chile and Argentina) plus Central and North America, (ii) northern Europe and (iii) Australasia, and two distinctive groups for the Short-eared Owl: (i) South America (Chile and Argentina) and (ii) north America plus northern Europe and northern Asia. The level of genetic divergence observed in both species exceeds the upper limit of intraspecific comparisons reported previously for Strigiformes. Therefore, this suggests that further research is needed to assess the taxonomic status, particularly for the Chilean populations that, to date, have been identified as belonging to these species through traditional taxonomy.  相似文献   

20.
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