首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
A new species of Asplundia from the Cordillera Central in Colombia is described and illustrated. Asplundia callejasii is placed in A. subg. Asplundia, based on the morphology of the staminate flowers. The most distinctive characteristic of A. callejasii is its long leaves, with the blade unicostate, oblanceolate, shallowly divided, and very lustrous, with the plicate nerves forming roughly 45° angles with the midrib. These features give it a unique aspect that sets it apart from any other species within the family.  相似文献   

2.
Multilocus DNA sequence-based identification methods raised the number of known species assigned to the Aspergillus section Versicolores. Currently, there are 16 species accepted in the section, including A. amoenus, A. austroafricanus, A. creber, A. cvjetkovicii, A. fructus, A. griseoaurantiacus, A. hongkongensis, A. jensenii, A. protuberus, A. puulaauensis, A. subversicolor, A. sydowii, A. tabacinus, A. tennesseensis, A. venenatus, and A. versicolor. Based on morphological identifications, most of these species were identified as either A. sydowii or A. versicolor, with the latter reported to have a world-wide distribution, growing in many habitats. Aspergillus versicolor has been implicated in health hazards including sick building syndrome, human and animal mycoses, and contamination of food and feed were assigned primarily to this species. A. versicolor is still commonly isolated from indoor surveys, even though species such as A. jensenii and A. creber seem more common. From indoor air samples collected at a grain mill in Croatia, we isolated an undescribed species assigned to the Aspergillus section Versicolores. A polyphasic approach, including sequence-based methods, morphological and physiological studies, was used for species characterization and in this paper is described as Aspergillus pepii. Additionally, sterigmatocystin producing abilities have been confirmed. Based on a combined phylogenetic tree, morphological features and sterigmatocystin producing abilities, A. pepii is closely related to A. versicolor. Further studies should explore the frequency of the species in indoor environments and its medical, industrial, and environmental significance.  相似文献   

3.
Rhizomatosae is a taxonomic section of the South American genus Arachis, whose diagnostic character is the presence of rhizomes in all its species. This section is of particular evolutionary interest because it has three polyploid (A. pseudovillosa, A. nitida and A. glabrata, 2n?=?4x?=?40) and only one diploid (A. burkartii, 2n?=?2x?=?20) species. The phylogenetic relationships of these species as well as the polyploidy nature and the origin of the tetraploids are still controversial. The present study provides an exhaustive analysis of the karyotypes of all rhizomatous species and six closely related diploid species of the sections Erectoides and Procumbentes by cytogenetic mapping of DAPI/CMA heterochromatin bands and 5S and 18–26S rDNA loci. Chromosome banding showed variation in the DAPI heterochromatin distribution pattern, which, together with the number and distribution of rDNA loci, allowed the characterization of all species studied here. The bulk of chromosomal markers suggest that the three rhizomatous tetraploid species constitute a natural group and may have at least one common diploid ancestor. The cytogenetic data of the diploid species analyzed evidenced that the only rhizomatous diploid species—A. burkartii—has a karyotype pattern different from those of the rhizomatous tetraploids, showing that it is not likely the genome donor of the tetraploids and the non-monophyletic nature of the section Rhizomatosae. Thus, the tetraploid species should be excluded from the R genome, which should remain exclusively for A. burkartii. Instead, the karyotype features of these tetraploids are compatible with those of different species of the sections Erectoides and Procumbentes (E genome species), suggesting the hypothesis of multiple origins of these tetraploids. In addition, the polyploid nature and the group of diploid species closer to the tetraploids are discussed.  相似文献   

4.
5.
Three new species of the gеnus Entoloma s.l. are described on the basis of morphological and molecular evidence. Two of them are morphologically and phylogenetically closely related to the European species E. violaceozonatum but differ sufficiently by their geographic distribution: E. bulakhae is from the Russian Far East and E. bidupense from Vietnam. The more distant E. atricolor from Vietnam is remarkable because of the brownish-black color of the basidiomata, blackish lamellae edge near the stem, and observed dimorphism in cheilocystidia. These three species are characterized by the combination of clamped basidia and a serrulatum-type lamellae edge and grouped together within the /Inocephalus–Cyanula clade in sister position to /Inocephalus and /Griseorubida. It is argued that they may possibly constitute a separate section in future, when more data will be available. For this reason, section Violaceozonata is proposed here “ad interim” to acknowledge the current isolated position.  相似文献   

6.
We describe a new cliff-dwelling species within Sonchus (Asteraceae): Sonchus boulosii and analyze its systematic position and evolutionary significance; in addition, we provide a key to the species of Sonchus in Morocco. Both morphological and ecological characteristics suggest a close relationship of S. boulosii with taxa of section Pustulati. However, ITS nrDNA and cpDNA matK markers indicate its uncertain position within the genus, but clear genetic differentiation from the remaining major clades. ITS phylogenetic trees show that likely evolutionary shifts to rocky habitat took place at least five times within genus Sonchus and that sect. Pustulati and S. boulosii clades have a clearly independent evolutionary origin. We postulate that the strong resemblance of S. boulosii to other rocky species reflects a phenomenon of homoplasy, probably driven by parallel evolutionary adaptations to the severe ecological constraints of its cliff face habitat. Therefore, a new section is also described, which includes S. boulosii as its sole representative: section Pulvinati. According to phylogenetic trees, the new clade may share its common ancestor with the clade comprising sections Maritimi and Arvenses, from which it is widely divergent in morphology and ecology, with the exception of Sonchus novae-zelandiae. However, the latter is a derived taxon, with high level of polyploidy unlike S. boulosii that shows 2n?=?18, basal chromosome number of the genus. Since sections Pulvinati and Pustulati seem to be quite old in Sonchus, we also hypothesize that some similarities, such as fruit morphology, may reflect the persistence of some primitive characteristics.  相似文献   

7.
During the spring and summer of 2014 and 2015, wheat and barley fields in the Iranian provinces of Golestan and Alborz showed a high incidence of symptoms of black (sooty) head mold of wheat and barley. The isolation results revealed that Alternaria was associated with these symptoms. One hundred and forty isolates were collected and morphologically characterized based on the development of conidial chains with primary, secondary, and tertiary branching patterns, consistent with the three-dimensional sporulation complexity of members of Alternaria in sections Infectoriae and Pseudoalternaria. Subsequently, 16 Alternaria isolates exhibiting high morphological diversity were characterized based on extensive morphological and molecular comparisons. Phylogenetic analyses of three loci [ITS, glyceraldehyde 3-phosphate dehydrogenase (gpd), and plasma membrane ATPase (ATPase)] revealed that 15 isolates belonged to section Infectoriae but could not be assigned to phylogenetic species and one isolate represents a new species, Alternaria kordkuyana sp. nov., in section Pseudoalternaria. Morphological assessments revealed a high degree of variation among section Infectoriae isolates and that A. kordkuyana has significant morphological differences as compared to the three other species currently described in section Pseudoalternaria.  相似文献   

8.
Cortinarius coalescens Kärcher & Seibt is a rare European species of the subgenus Phlegmacium, section Phlegmacioides, neglected in recent molecular studies. New primers (CortF and CortR) designed for species in the section Phlegmacioides allowed to obtain ITS rDNA sequence data from the holotype collection of C. coalescens; according to the results, this epithet has priority over C. crassorum Rob. Henry ex Rob. Henry, C. pardinus Reumaux, and C. parargutus Bidaud, Moënne-Locc. & Reumaux. Morphological and ecological observations on recent collections of C. coalescens from the Czech Republic in comparison with the co-occurring C. largus are discussed. Nomenclatural and taxonomic comments on C. tomentosus Rob. Henry, C. balteatotomentosus Rob. Henry, and C. subtomentosus Reumaux are also provided. So far, C. coalescens is known with certainty from Germany, France, and the Czech Republic, where it grows in deciduous forests on acid to neutral soils. Arsenic and its compounds were determined in C. coalescens and related species of the section Phlegmacioides: C. largus, C. pseudodaulnoyae, and C. variecolor. Total arsenic concentrations were in the range 3.6–30.2 mg kg?1 (dry matter) and arsenobetaine was the major arsenic compound.  相似文献   

9.
A new species, Betula erkovetskiensis Blokhina et O.V. Bondarenko (Betulaceae), from the deposits of the Sazanka Formation (upper Middle?Upper Miocene) of the Erkovetskii Brown Coal Field (Amur Region, Russia) is described based on anatomical features of fossil wood. The new species shows some wood anatomical characters of the extant birch subgenus Betula, B. davurica, B. nigra (section Dahuricae), and B. papyrifera (section Betula). Fossil wood of Betula is found in the Amur Region for the first time.  相似文献   

10.
Cortinarius is one of the most species-rich genera of mushroom-forming fungi. Based on phylogenetic and morphological evidence, Cortinarius, sect. Riederi, is introduced at sectional level (= subsect. Riederi sensu Brandrud & Melot). The taxonomy, phylogeny, ecology and distribution of not only mainly European but also including some North American taxa of this section are treated, which includes nine species and two varieties. Of these, three taxa are described as new (C. burlinghamiae, C. pallidoriederi and C. argenteolilacinus var. dovrensis). The sect. Riederi species possess morphological features similar to Phlegmacium group(s) and forms a phylogenetically isolated lineage, with no supported affinity to other phlegmacioid groups. Three taxa are known from both Europe and North America, two species are known only from North America and five only from Europe. Altogether, eight of the ten taxa are associated with conifers or northern (boreal-subalpine) deciduous trees (Betula spp.). Only two species occur in more temperate forests (Fagus forests), and no species have so far been found in thermophilous Quercus forests  相似文献   

11.
Two novel Aspergillus species, one belonging to the section Terrei and the other to section Flavipedes, were isolated from hypersaline soils of The National Park of Lake Urmia (Iran) and are here described as Aspergillus iranicus and Aspergillus urmiensis. A polyphasic taxonomic approach comprising extrolite profiles, phenotypic characters and molecular data (beta-tubulin, calmodulin and ribosomal polymerase II second largest subunit gene sequences) was applied to determine their novel taxonomic status. Aspergillus iranicus (CBS 139561T) is phylogenetically related to A. carneus, A. niveus, A. allahabadii and A. neoindicus, and it can be differentiated from those species by a unique extrolite pattern (citrinin, gregatins, and a terrequinone) and its conidial colour. Aspergillus urmiensis (CBS 139558T) shares a most recent common ancestor with A. templicola. The former species produces globose vesicles, and those of A. templicola are predominantly elongate. The Aspergillus urmiensis isolates produce several uncharacterized extrolites. Two other strains obtained during this study reside in a clade, together with the type strain of A. movilensis (CCF 4410T), and are identified accordingly. Based on the phylogenetic data presented in this study, A. frequens is reduced to synonymy with A. micronesiensis and A. mangaliensis is considered to be a synonym of A. templicola.  相似文献   

12.
Betulaceae have simple flowers but complex inflorescences. Recent phylogenetic analyses using molecular data have produced robust phylogenetic trees of Betulaceae. In this study, we evaluated the phylogenetic value of comparative organogenetic data of reproductive organs in the context of molecular phylogenies. Flower and inflorescence developmental processes of 21 species from all six genera in Betulaceae were documented with scanning electron microscopy. In each pistillate cyme, there are one primary bract, two secondary bracts, and two or three flowers in the six genera; only in Alnus are there two tertiary bracts on the abaxial side. The pistillate flower of all genera but Alnus has tepal primordia. Two tepals stop developing early on, resulting in the lack of tepals in mature flowers of Betula; while the tepals are initiated from a common circular primordium at the base of pistil in Corylus, Ostryopsis, Carpinus, and Ostrya, and the developed tepals with irregular shape and unstable number of lobes are adnate to the top of the pistil. In staminate organogenesis, each cyme has one primary bract and three flowers in all genera; two secondary bracts are only present in Alnus, Betula, and Corylus. Staminate flowers have no tepals except in Alnus and Betula, and exhibit high variation in number of stamens among genera. The number of secondary and tertiary bracts in each pistillate and staminate cyme, as well as the presence of tepals in pistillate and staminate flowers was clarified in all genera. Micro-morphological characters were used to infer the phylogenetic relationships of genera and sections of Betulaceae. Our analyses support the division of two subfamilies: Betuloideae (Alnus and Betula) and Coryloideae (Corylus, Carpinus, Ostrya, and Ostryopsis), and three tribes: Betuleae (Alnus and Betula), Coryleae (Corylus), and Carpineae (Carpinus, Ostrya, and Ostryopsis). The results agree with those from molecular phylogenetic studies, and suggest that micro-morphological characters are phylogenetically informative in Betulaceae, and reproductive organs of Betulaceae have evolved in the direction of reduction in bracts and tepals.  相似文献   

13.
In this study fecal microflora of human infants born through vaginal delivery (VB) and through cesarean section (CB) were investigated using culture-independent 16S rDNA cloning and sequencing approach. The results obtained clearly revealed that fecal microbiota of VB infants distinctly differ from those in their counterpart CB infants. The intestinal microbiota of infants delivered by cesarean section appears to be more diverse, in terms of bacteria species, than the microbiota of vaginally delivered infants. The most abundant bacterial species present in VB infants were Acinetobacter sp., Bifidobacterium sp. and Staphylococcus sp. However, CB infant’s fecal microbiota was dominated with Citrobacter sp., Escherichia coli and Clostridium difficile. The intestinal microbiota of cesarean section delivered infants in this study was also characterized by an absence of Bifidobacteria species. An interesting finding of our study was recovery of large number of Acinetobacter sp. consisting of Acinetobacter pittii (former Acinetobacter genomic species 3), Acinetobacter junii and Acinetobacter baumannii in the VB infants clone library. Among these, Acinetobacter baumannii is a known nosocomial pathogen and Acinetobacter pittii (genomic species 3) is recently recognized as clinically important taxa within the Acinetobacter calcoaceticusAcinetobacter baumannii (ACB) complex. Although none of the infants had shown any sign of clinical symptoms of disease, this observation warrants a closer look.  相似文献   

14.
We describe two new, mainly North European species of basidiomycetous fungi. Cortinarius stjernegaardii belongs to the section Percomes containing several similar species with greenish-yellow, anthraquinonoid pigments and peculiar smells. The species has hitherto been identified as” C. bulbopodius” in the Nordic countries, an epithet which, however, is reduced to a synonym of C. aurilicis. Cortinarius kristinae belongs to the section Calochroi, which includes many morphologically similar species with sharply marginate bulbose stipes and yellow pileus colours. The species are distinguished from related taxa by molecular data (ribosomal ITS region), and typical specimens can be identified by a combination of basidiocarp coloration, stature, microscopy, reactions with KOH, and habitat.  相似文献   

15.
16.
The genus Riasanites, represented in Central Russia by two successive dimorphic species, is revised. R. swistowianus is found in the basal beds of the rjasanensis Zone. Its descendant R. rjasanensis is also found in this zone, but upwards in the section, including the beds with Surites spasskensis and Externiceras solowaticum. The representatives of Riasanites from the Crimea and Northern Caucasus are assigned to two species, R. crassicostatus and R. maikopensis, respectively. It is suggested that Riasanites evolved from Sub-Mediterranean Himalayatidae, which migrated from the Western Tethys via the Polish Passage into the Central Russian Basin, and from there to Mangyshlak, the Northern Caucasus, and the Crimea.  相似文献   

17.
One of the most enigmatic and unusual groups in the passionflower genus, Passiflora section Dysosmia (Passifloraceae), stands out as a group that is notoriously taxonomically complicated. Phenetic and cladistic analyses of Dysosmia were carried out with representatives from all 21 species currently recognized in the section, in order to delineate morphological groups above the species level. The study was based mainly on vegetative morphological characters and included principal coordinates, non-metric multidimensional scaling, cluster, and cladistic analyses. Results from each analysis reveals that three major species assemblages exist within Dysosmia, corresponding largely to vegetative pubescence and fruit color. The results presented here set the stage for future systematic and phylogenetic studies in Passiflora sect. Dysosmia.  相似文献   

18.
We investigate the timing of diversification in allopolyploids of Nicotiana (Solanaceae) utilising sequence data of maternal and paternal origin to look for evidence of a lag phase during which diploidisation took place. Bayesian relaxed clock phylogenetic methods show recent allopolyploids are a result of several unique polyploidisation events, and older allopolyploid sections have undergone subsequent speciation at the polyploid level (i.e. a number of these polyploid species share a singular origin). The independently formed recent polyploid species in the genus all have mean age estimates below 1 million years ago (Ma). Nicotiana section Polydicliae (two species) evolved 1.5 Ma, N. section Repandae (four species) formed 4 Ma, and N. section Suaveolentes (~35 species) is about 6 million years old. A general trend of higher speciation rates in older polyploids is evident, but diversification dramatically increases at approximately 6 Ma (in section Suaveolentes). Nicotiana sect. Suaveolentes has spectacularly radiated to form 35 species in Australia and some Pacific islands following a lag phase of almost 6 million years. Species have filled new ecological niches and undergone extensive diploidisation (e.g. chromosome fusions bringing the ancestral allotetraploid number, n = 24, down to n = 15 and ribosomal loci numbers back to diploid condition). Considering the progenitors of Suaveolentes inhabit South America, this represents the colonisation of Australia by polyploids that have subsequently undergone a recent radiation into new environments. To our knowledge, this study is the first report of a substantial lag phase being investigated below the family level.  相似文献   

19.
Russula lotus, R. nivalis, and R. purpureoverrucosa are proposed here as new taxa based on morphological and molecular evidences. The new species are described with illustration photographs and line drawings, and compared against related species. Morphologically, R. lotus (subgenus Heterophyllidia, section Heterophyllae, subsection Cyanoxanthinae) is characterized by a medium-sized basidioma with a pale pink to purplish pink pileus whose center area is yellowish white, white to cream white lamellae occasionally forked with lamellulae, a cream white smooth stipe, broadly ellipsoid to ellipsoid basidiospores ornamented with disconnected amyloid warts and inamyloid suprahilar plage, dispersed sulphovanillin (SV)-negative pileocystidia, and the pileipellis with suprapellis cells claw-assembled. Russula nivalis (subgenus Russula, section Russula, subsection Russula) is characterized by a very small pure white basidioma with a pileus 7–12 mm in diameter, abundant clavate pileocystidia and caulocystidia changing purplish red in SV, and broadly ellipsoidal to ellipsoid basidiospores ornamented with strongly amyloid warts and ridges interconnected by fine lines in an uncompleted or completed reticulum, mostly with inamyloid suprahilar plage. Russula purpureoverrucosa (subgenus Incrustatula, section Lilaceinae, subsection Lilaceinae) is characterized by a medium-sized basidioma with a red to grayish magenta pileus slightly areolate in small irregular warts from center to margin, a stipe with the same color and warts as the pileus, white to cream white occasionally forked lamellae with lamellulae, broadly ellipsoidal to ellipsoid basidiospores ornamented with amyloid warts and ridges rarely connected, abundant clavate pleurocystidia covered with thick yellowish incrustations, and the pileipellis with suprapellis cells a typical trichoderm, some of which covered with yellowish incrustations, pileocystidia absent. Phylogenetic analysis of nucleotide sequences of the internal transcribed spacer (ITS) region provided further evidence that the described species belong to the subsections above respectively, and represent new taxa.  相似文献   

20.
Various Talaromyces strains were isolated during a survey of fungi involved in leaf litter decomposition in tropical lowland forests in the Caquetá and Amacayacu areas of the Colombian Amazon. Four new Talaromyces species are described using a polyphasic approach, which includes phenotypic characters, extrolite profiles and phylogenetic analysis of the internal transcribed spacer region (ITS) barcode, and beta-tubulin (BenA) and calmodulin (CaM) gene regions. Talaromyces amazonensis sp. nov., T. francoae sp. nov. and T. purgamentorum sp. nov. belong to Talaromyces section Talaromyces, and T. columbiensis sp. nov. is located in section Bacillispori. The new species produce several bioactive compounds: T. amazonensis produces the potential anticancer agents duclauxin, berkelic acid and vermicillin, and T. columbiensis produces the effective anticancer agent wortmannin (together with duclauxin). In addition to the new species, T. aculeatus and T. macrosporus were isolated during this study on leaf litter decomposition.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号