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1.
A new family, Vidronovellidae, with a new genus, Vidronovella, and its type species V. fastigata sp. nov., and a new species, Europora gerirudensis, are described from the Famennian of Afghanistan, and the new species Primorella iranica, Heloclema magnificum, and Worthenopora elbursensis are described from the Viséan of Iran.  相似文献   

2.
The sesquiterpene lactones isolated from species in the genus Artemisia have been reviewed in an attempt to better understand the phylogeny and systematics of the four sections (subgenera), Abrotanum, Absinthium, Dracunculus and Seriphidium, proposed by Besser in 1829. The absence of hair on the receptacle is the only morphological characteristic separating species of Abrotanum from the species of Absinthium. There are no chemical characteristics segregating the species in these two subgenera since both produce eudesmanolides and guaianolides that are identical or biosynthetically similar. This suggests that the two subgenera could be combined into one (Artemisia) as proposed by Poljakov. The subgenus Seriphidium is composed of two geographical groups, one in the Old World and the other in the New World. The Old World species almost exclusively produce sesquiterpene lactones in the eudesmanolide class whereas the New World species (section Tridentatae) produce eudesmanolides and guaianolides, many of the latter being identical or structurally related to the sesquiterpene lactones in New World Abrotanum species. The chemical data in conjunction with geographic distributions suggest that the subgenus Seriphidium is polyphyletic and that the section Tridentatae originated from Abrotanum. Consequently, the Tridentate should be recognized as a subgenus separate and distinct from the Old World Seriphidium. There was insufficient information from the subgenus Dracunculus for interpretation.  相似文献   

3.
This paper provides a list of 125 species from 22 families of Microlepidoptera collected in the south of Krasnoyarsk Territory and in the Republic ofKhakassia, with 63 species (50%) and 2 families (Bucculatricidae and Elachistidae) recorded in the region for the first time, and 11 species from 6 families being new to Siberia: Cauchas fibulella, Nemophora fasciella, N. minimella (Adelidae), Phyllonorycter sorbicola, Phyllocnistis extrematrix (Gracillariidae), Cosmiotes freyerella, Elachista subocellea (Elachistidae), Caryocolum alsinella, Scrobipalpula diffluella (Gelechiidae), Agonopterix intersecta (Depressariidae), and Ypsolopha horridella (Ypsolophidae). Three species are new to science: Phyllonorycter sp. and Phyllocnistis verae (Gracillariidae) from the suburbs of Krasnoyarsk and Chrysoesthia sp. (Gelechiidae) from the Republic of Khakassia. Almost half of the faunistic findings belong to two families, Gelechiidae (34 species) and Gracillariidae (24 species). In the former family, the number of species distributed in Krasnoyarsk Territory and/or Khakassia was increased by 1.5 times based on our collection. Trophic specialization remains unknown only for 7 of the 125 species. Most (90%) of the remaining 118 species are phytophagous, the others are saprophagous; 53 species are known as leaf miners. Phytophagous species feed on plants of 36 families and 21 orders. The largest number of microlepidopteran species inhabit plants of the orders Rosales and Fagales (25 and 24 species, respectively). Twelve species are known as pests: Tineidae (4 species), Gracillariidae, Gelechiidae (2 species in each), Argyresthiidae, Choreutidae, Lyonetiidae, and Plutellidae (one species in each). Four pest species have expanded beyond the Palaearctic in the last century: Choreutis pariana (Choreutidae), Scrobipalpa atriplicella (Gelechiidae), Plutella xylostella (Plutellidae), and Niditinea fuscella (Tineidae).  相似文献   

4.
Twenty-one flavonoids were isolated from the leaves of two endemic species ofMyrceugenia on the Juan Fernandez Islands,M. fernandeziana andM. schulzei, from two related species from Brazil,M. campestris andM. rufescens, and from five species from continental Chile,M. colchaguensis, M. exsucca, M. lanceolata, M. pinifolia, andM. rufa. A phenetic analysis was used to evaluate chemical similarities.Myrceugenia campestris andM. rufescens appear most closely related to each other based on flavonoid profiles, and they are also different from the other seven species. The two endemic species in the Juan Fernandez Islands,M. fernandeziana andM. schulzei, group with the continental Chilean species. The former is most closely related toM. lanceolata, and the latter clusters withM. exsucca, although somewhat distantly. The results suggest that the two Juan Fernandez endemics are derived from two introductions from the Chilean continent and not from immigrants from the eastern side of the Andes.  相似文献   

5.
Competitive ability, the ability to generate legacy effects, and the potential to benefit from priority, individually or interactively, are traits that may increase the invasive potential of plants. In this project we examine these three traits in three invasive species (Agropyron cristatum, Bromus tectorum, and Taeniatherum caput-medusae). Specifically in this study, we examine competitive effects of these invasive species, the ability of these invasive species to generate legacy effects (as plant–soil feedback), and the potential of these three species benefit from priority (being sown concurrently, 30 days before, and 30 days after the restoration species) in a greenhouse study using field collected soil. Our results suggest that all three invasive species can benefit from priority and all three have high competitive ability. However, only A. cristatum benefited from legacy effects of plant–soil feedback.  相似文献   

6.
All sexually fertile strains in the Gibberella fujikuroi species complex are heterothallic, with individual mating types conferred by the broadly conserved ascomycete idiomorphs MAT-1 and MAT-2. We sequenced both alleles from all eight mating populations, developed a multiplex PCR technique to distinguish these idiomorphs, and tested it with representative strains from all eight biological species and 22 additional species or phylogenetic lineages from this species complex. In most cases, either an ~800-bp fragment from MAT-2 or an ~200-bp fragment from MAT-1 is amplified. The amplified fragments cosegregate with mating type, as defined by sexual cross-fertility, in a cross of Fusarium moniliforme (Fusarium verticillioides). Neither of the primer pairs amplify fragments from Fusarium species such as Fusarium graminearum, Fusarium pseudograminearum, and Fusarium culmorum, which have, or are expected to have, Gibberella sexual stages but are thought to be relatively distant from the species in the G. fujikuroi species complex. Our results suggest that MAT allele sequences are useful indicators of phylogenetic relatedness in these and other Fusarium species.  相似文献   

7.
Phymosomatoid echinoids from the Campanian and the Maastrichtian of Belgium and the Netherlands are systematically revised. Ten species, belonging to four genera are identified and described. One new species is introduced:Gauthieria?mosae sp. nov.  相似文献   

8.
Numerous hybrid and polypoid species are found within the Triticeae. It has been suggested that the H subgenome of allopolyploid Elymus (wheatgrass) species originated from diploid Hordeum (barley) species, but the role of hybridization between polyploid Elymus and Hordeum has not been studied. It is not clear whether gene flow across polyploid Hordeum and Elymus species has occurred following polyploid speciation. Answering these questions will provide new insights into the formation of these polyploid species, and the potential role of gene flow among polyploid species during polyploid evolution. In order to address these questions, disrupted meiotic cDNA1 (DMC1) data from the allopolyploid StH Elymus are analyzed together with diploid and polyploid Hordeum species. Phylogenetic analysis revealed that the H copies of DMC1 sequence in some Elymus are very close to the H copies of DMC1 sequence in some polyploid Hordeum species, indicating either that the H genome in theses Elymus and polyploid Hordeum species originated from same diploid donor or that gene flow has occurred among them. Our analysis also suggested that the H genomes in Elymus species originated from limited gene pool, while H genomes in Hordeum polyploids have originated from broad gene pools. Nucleotide diversity (π) of the DMC1 sequences on H genome from polyploid species (π = 0.02083 in Elymus, π = 0.01680 in polyploid Hordeum) is higher than that in diploid Hordeum (π = 0.01488). The estimates of Tajima''s D were significantly departure from the equilibrium neutral model at this locus in diploid Hordeum species (P<0.05), suggesting an excess of rare variants in diploid species which may not contribute to the origination of polyploids. Nucleotide diversity (π) of the DMC1 sequences in Elymus polyploid species (π = 0.02083) is higher than that in polyploid Hordeum (π = 0.01680), suggesting that the degree of relationships between two parents of a polyploid might be a factor affecting nucleotide diversity in allopolyploids.  相似文献   

9.
The Pseudoroegneria species are perennial grasses in the Triticeae tribe, whose St genome has been linked to several important polyploid species. Due to frequent hybridization and complex genetic mechanism, the relationships within Pseudoroegneria, and within the Triticeae have been heavily disputed. Using the chloroplast rbcL gene we estimated the nucleotide diversity of 8 Pseudoroegneria species. We also examined the phylogenetic relationships within Pseudoroegneria and of Pseudoroegneria within the Triticeae. The estimates of nucleotide diversity indicated that Pseudoroegneria tauri and Pseudoroegneria spicata species had the highest diversity, while Pseudoroegneria gracillima had the lowest diversity. The phylogenetic analysis of Pseudoroegneria placed all P. spicata species into a clade separate from the other Pseudoroegneria species, while the relationship of the other Pseudoroegneria species could not be determined. Due to the groupings of Pseudoroegneria with the polyploid Elymus, our results strongly supported Pseudoroegneria as the maternal genome donor to Elymus. There was also weak support that P. spicata may be the maternal donor to the StH Elymus species.  相似文献   

10.
11.
Molecular diversity in the primary and secondary gene pools of genus Oryza   总被引:1,自引:0,他引:1  
The objective of the present investigation was to assess the genetic relationships among the species of Oryza that belong to the primary gene pool (sativa complex) and the secondary gene pool (officinalis complex) using three marker systems such as RAPDs, ISSRs and SSRs. A total of 432 clear and reproducible bands were amplified from 18 RAPD primers; 113 bands were detected from 8 ISSR primers and 78 alleles were found to be amplified across the Oryza species from 13 SSR primer pairs. All the three dendrograms constructed, using UPGMA from the genetic similarity matrices based on the three marker data sets, were similar in their groupings. In all the three trees, two accessions of Oryza sativa formed an exclusive group indicating its genomic differentiation from its wild ancestors through the process of domestication. Distinctness between the wild species of the sativa and officinalis complexes was evident in all the trees derived from different markers. The groupings obtained among the species of the sativa complex were in perfect concordance with the species relationships established through classical crossability and cytogenetic analysis. This study has brought out some information on the species relationship between the diploid and tetraploid genomes of the officinalis complex possessing BB, CC and DD genomes. The higher level of similarity observed between the species possessing C and D genomes supports the view of many earlier authors that these two genomes might have originated from a single hybridization event. The results of this study also show that the diploid species possessing C genomes such as Oryza officinalis, Oryza rhizomatis and Oryza eichingeri are distinct from their allotetraploid counterparts possessing BBCC and CCDD genomes indicating a wider genomic differentiation in their evolutionary process.  相似文献   

12.
13.
Middle Triassic marine deposits of the Germanic Basin (Muschelkalk) record a significant proliferation of cementing bivalves from different families. Based on previously undescribed, excellently preserved material from the Willebadessen Member (late Anisian, Illyrian) of the Upper Muschelkalk Trochitenkalk Formation of Willebadessen (Germany), we propose the new genus Noetlingiconcha, type species N. speculostreum sp. nov., for strongly plicate prospondylids lacking auricles. The new genus differs from Terquemia and Enantiostreon in being plicate rather than costate, and from Newaagia in the absence of auricles. We demonstrate that N. speculostreum was invariably attached by its right valve, in contrast to an externally similar species from the Lower Muschelkalk Freudenstadt Formation (lower Anisian, Bithynian) that was exclusively cemented by its left valve and thus represents the geologically oldest known oyster species. Previous reports of amphi-pleurothetic cemented bivalve species from the Muschelkalk probably result from lumping together these two externally similar species. The constancy of sinistral attachment in the geologically oldest Ostreidae suggests that left-pleurothetic valve orientation was already established in the ancestry of this family. Palaeontological data are therefore in accordance with genetic and larval shell morphology analyses that identified Pterioidea as the sister taxon of Ostreoidea, because Pterioidea contains several Permian-Triassic genera with an anatomically lower left valve.  相似文献   

14.
Among the multiple factors involved in the decline of amphibians, competition with alien species remains understudied. In Western Europe, non-native marsh frogs (Pelophylax ridibundus and other sister species) have been widely imported for gastronomic purposes and have then often escaped from captivity. Apart from closely related species, the impact of the subsequent colonization of non-native species on native amphibians is still unknown. In this study, we analysed the response of a threatened species, the yellow-bellied toad (Bombina variegata), faced with the presence of alien frogs in mountain rivers in France. We studied the co-occurrence pattern of the native toad and the alien frog, while taking into account co-dependence of the detection rates in both species. We tested three main scenarios to explain a non-random pond occurrence for each species and to establish their respective habitat preferenda: (1) a pond-area-dependent scenario, predicting different responses from each species for a given pond size, (2) a fish-dependent scenario, predicting different responses from each species given the presence of fish in ponds, and (3) a floodplain-width-dependent scenario, predicting different responses from each species given the geomorphological characteristics of the floodplain. Taking into account site-specific covariates, we concluded that introduced frogs do not currently have an impact on the native population of the yellow-bellied toad.  相似文献   

15.
The Achromobacter is a genus in the family Alcaligenaceae, comprising fifteen species isolated from different sources, including clinical samples. The ability to detect and correctly identify Achromobacter species, particularly A. xylosoxidans, and differentiate them from other phenotypically similar and genotypically related Gram-negative, aerobic, non-fermenting species is important for patients with cystic fibrosis (CF), as well as for nosocomial and other opportunistic infections. Traditional phenotypic profile-based analyses have been demonstrated to be inadequate for reliable identifications of isolates of Achromobacter species and genotypic-based assays, relying upon comparative 16S rRNA gene sequence analyses are not able to insure definitive identifications of Achromobacter species, due to the inherently conserved nature of the gene. The uses of alternative methodologies to enable high-resolution differentiation between the species in the genus are needed. A comparative multi-locus sequence analysis (MLSA) of four selected ‘house-keeping’ genes (atpD, gyrB, recA, and rpoB) assessed the individual gene sequences for their potential in developing a reliable, rapid and cost-effective diagnostic protocol for Achromobacter species identifications. The analysis of the type strains of the species of the genus and 46 strains of Achromobacter species showed congruence between the cluster analyses derived from the individual genes. The MLSA gene sequences exhibited different levels of resolution in delineating the validly published Achromobacter species and elucidated strains that represent new genotypes and probable new species of the genus. Our results also suggested that the recently described A. spritinus is a later heterotypic synonym of A. marplatensis. Strains were analyzed, using whole-cell Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight mass spectrometry (MALDI-TOF MS), as an alternative phenotypic profile-based method with the potential to support the identifications determined by the genotypic DNA sequence-based MLSA. The MALDI-TOF MS data showed good accordance in strain groupings and identifications by the MLSA data.  相似文献   

16.
Abstract:Biatora britannica sp. nov. is described from Wales. The species is the sorediate sister taxon of the Madeiran Biatora hertelii. The close relationship is supported by the presence of the hymenial pigment Hertelii-green, which is hitherto known only from these two species. Molecular data from the nuclear ITS-region of 14 Biatora -species renders further support for the close relationship of both species. Sterile, sorediate material from the British Isles earlier referred to B. efflorescens may in fact belong to B. britannica.  相似文献   

17.
RAPD markers were generated from 13 different Rubus species in order to assess the degree of similarity between species from the important subgenera. All ten primers revealed scorable polymorphisms within both the closely related and the genetically diverse individuals. Three hundred and seventy-two markers were generated and scored from the material analysed. Estimates of similarity, dendrograms and principle co-ordinate analysis were calculated, with the results generally being in agreemen with previous classifications of the species studied, confirming the validity and usefulness of the RAPD method. However, amongst the species studied, R. macraei of the Idaeobats proved more diverse and grouped in with both the Idaeobats and Eubats at only 26% similarity.  相似文献   

18.
Four new species, Machilinus caucasicus (Meinertellidae), Trigoniophthalmus fuscus, T. petrophilus, and Silvestrichilis zazimkoi from Krasnodar Territory, and one new species, Allopsontus linnaeusi (Machilidae) from Eastern Kazakhstan are described. A key to species of the genus Trigoniophthalmus is given.  相似文献   

19.
The earliest Eocene locality of Dormaal (Belgium) has provided the oldest Cenozoic herpetotheriid marsupials of Europe. No herpetotheriid has ever been reported earlier than the Eocene in Europe, except for a questionable single upper molar from the Upper Cretaceous of the Belgian/Dutch border. The systematics of the herpetotheriids of Dormaal was formerly based on only a dozen dental specimens, which were assigned, after several revisions, to two species Peratherium constans and Amphiperatherium brabantense. Most importantly, these two species were considered at the root of most of the hepetotheriid lineages of the European Paleogene. Here we report a large sample of about 400 new dental remains that allow a better definition of both species as well as a testing of their systematic status. The evidence of significant morphological variability leads us to reconsider the diagnosis of Peratherium constans and to question the validity of Amphiperatherium brabantense. This study highlights that the primitive species Peratherium constans and Amphiperatherium brabantense are hardly distinguishable from each other, and therefore conclude that Peratherium constans was the only marsupial present at Dormaal. The important morphological variation exhibited by this herpetotheriid is similar to the variability observed in the type-species Peratherium elegans and in other fossil and extant metatherians. Consequently, our results suggest that several Amphiperatherium species from the Eocene could represent variants of the genus Peratherium. The question of the Amphiperatherium presence in Europe is therefore raised and a thorough discriminate analysis of both genera should be conducted in later works.  相似文献   

20.
Closely related species of gall-forming aphids are often associated with a single host species. SixTetraneura species coexist on the Japanese elm,Ulmus davidiana, in Sapporo, northern Japan. This paper describes the probabilities of coexistence on macro- and microgeographic scales (i.e., on host trees and host leaves) and examines whether coexistence with conspecific or heterospecific galls on leaves or shoots has any effect on the fecundity of each aphid species using multiple regression. A Monte Carlo simulation showed that the frequency distribution of the numbers of species on individual host trees differed significantly from that expected from the null model. There were significantly positive or negative associations between species.Tetraneura radicicola andsorini always coexisted with other species on trees they infested. Multiple regression revealed that the coexistence of conspecific or heterospecific galls on individual leaves had no influence on the fecundity ofradicicola andsorini, but had a negative influence on that of sp. O. On average,radicicola andsorini produced a smaller number of offspring in galls than sp. O, and obviously consumed only a small part of resources available on the galled leaves. Evidence available suggests that although amensalism does arise between sp. O and other species, its influence in not so strong as to exclude sp. O competitively from theTetraneura community.  相似文献   

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