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.
The taxonomic placement of four antarctic species of the marine red algal family Phyllophoraceae (Gigartinales) is assessed within a preliminary molecular phylogeny of the family based on direct sequence analysis of the chloroplast gene rbcL. Parsimony analysis of rbcL sequences indicates that Gymnogongrus antarcticus and Gymnogongrus turquetii cluster in a clade consisting predominantly of southern hemisphere species currently placed in Gymnogongrus and Ahnfeltiopsis, whereas Phyllophora ahnfeltioides and Phyllophora antarctica cluster in a separate clade that is widely divergent from the northern hemisphere Phyllophora clade. Results from molecular and morphological data challenge the current taxonomic concept that type of life history is a phylogenetically valid criterion for recognition of genera in the Phyllophoraceae.  相似文献   

2.
A taxonomic review of the genus Copelatus Erichson (Coleoptera: Dytiscidae) in Korea is presented. In the present study, five species of Copelatus are recognized from Korea, including one unrecorded species, C. kammuriensis. We provide a key to the Korean species of Copelatus, diagnosis of one unrecorded species, habitus photographs, scanning electron micrographs of the elytron, and illustrations of the aedeagus.  相似文献   

3.
The morphology and morphogenesis of Rigidohymena inquieta (Stokes, 1887) Berger, 2011, isolated from a lawn soil in the campus of the University of Ulsan, Korea, was studied, using live observation and protargol impregnation. The molecular phylogeny was studied based on the SSU rRNA gene sequences. The morphology of the Korean population of R. inquieta matches the previously known populations; however, the morphogenetic pattern shows differences to the species R. candens in the involvement of cirrus V/3 in the anlagen formation. A novel genus namely Metahymena gen. nov. has been erected for the present species based on the ontogenetic difference, and the new combination Metahymena inquieta gen. nov., comb. nov. is proposed. The morphology, morphogenesis, distribution, and phylogeny of M. inquieta are presented. The morphologic and morphogenetic data corroborate the phylogenetic analyses as M. inquieta clusters among the stylonychid ciliates in a clade distant from Rigidohymena candens.  相似文献   

4.
In August and September 2014, Korean ginseng (Panax ginseng) plants showing symptoms of powdery mildew infection were found in a polyethylene film‐covered greenhouse in Suwon, Korea. The mildew was initially observed to occur in circular to irregular white colonies, which subsequently developed into abundant mycelial growths on both leaf surfaces. No chasmothecia were observed. Based on its morphological characteristics, the fungus was determined to be a species of Erysiphe. Phylogenetic analysis of the sequence of the internal transcribed spacer region of the ribosomal DNA obtained from the isolate placed the powdery mildew fungus in the genus Erysiphe. Here, we describe this Erysiphe sp. found growing on Korean ginseng using both illustrations and molecular data. A comparison of the Korean isolate and three previous records of powdery mildews known to grow on Panax plants is also provided. This is the first report of powdery mildew on Korean ginseng in Korea.  相似文献   

5.
Over the past few decades, use of molecular markers for species delimitation has drastically increased. Schoenoplectiella Lye has been recognized as a taxonomically difficult genus because of its morphological simplicity and frequent interspecific hybridization. The main objective of this study was to clarify the taxonomic identities of eight Schoenoplectiella species by use of molecular markers. We also evaluated the genetic relationships among S. × trapezoidea, known as a natural hybrid, and its close relatives. We used six microsatellite markers for 44 individuals from 31 natural populations of eight Schoenoplectiella species in South Korea. Six microsatellite marker combinations generated 59 amplification-detectable bands, of which 33 were specifically detected in one or more individuals of each species. Cluster analysis revealed that the grouping was consistent with the taxonomically recognized species. Our results do not support the hybrid origin of S. × trapezoidea. Rather, they suggest that this species is more closely related to S. hotarui. The informative microsatellite markers enabled us to clarify the distinctions among Schoenoplectiella species from South Korea and to identify the genetic relationships among these species. The molecular signatures found suitable for accurate identification of Schoenoplectiella species can be reliably used for studies of the phylogeny and evolution of this genus.  相似文献   

6.
The Order Stolidobranchiata comprises the families Pyuridae, Styelidae and Molgulidae. Early molecular data was consistent with monophyly of the Stolidobranchiata and also the Molgulidae. Internal phylogeny and relationships between Styelidae and Pyuridae were inconclusive however. In order to clarify these points we used mitochondrial and nuclear sequences from 31 species of Styelidae and 25 of Pyuridae. Phylogenetic trees recovered the Pyuridae as a monophyletic clade, and their genera appeared as monophyletic with the exception of Pyura. The Styelidae, on the other hand, appeared as a paraphyletic group split into several clades. One of them was formed by solitary oviparous species, of which the Pyuridae were a sister group. A second clade included the colonial genera Botryllus, Botrylloides and Symplegma. The remaining colonial and solitary genera formed several poorly resolved clades. One of the more species genus, Polycarpa, was shown to be polyphyletic, and the species Styela plicata grouped into two genetically distant clades suggesting the existence of two cryptic species. The internal phylogeny of Styelidae has bearings on the origin of coloniality in this family. We suggest to abandon the traditional division of colonial forms into social and compound species and use instead the categories of aggregated colonies that do not have common vascular systems, and integrated colonies, that do possess such systems. Our molecular results indicate that there have been several independent acquisitions of coloniality in the Styelidae, and that viviparity may be a pre-adaptation for a colonial life-style.  相似文献   

7.
We report a new heterotrophic cryptomonad Hemiarma marina n. g., n. sp. that was collected from a seaweed sample from the Republic of Palau. In our molecular phylogenetic analyses using the small subunit ribosomal RNA gene, H. marina formed a clade with two marine environmental sequences, and the clade was placed as a sister lineage of the freshwater cryptomonad environmental clade CRY1. Alternatively, in the concatenated large and small subunit ribosomal RNA gene phylogeny, H. marina was placed as a sister lineage of Goniomonas. Light and electron microscopic observations showed that H. marina shares several ultrastructural features with cryptomonads, such as flattened mitochondrial cristae, a periplast cell covering, and ejectisomes that consist of two coiled ribbon structures. On the other hand, H. marina exhibited unique behaviors, such as attaching to substrates with its posterior flagellum and displaying a jumping motion. H. marina also had unique periplast arrangement and flagellar transitional region. On the basis of both molecular and morphological information, we concluded that H. marina should be treated as new genus and species of cryptomonads.  相似文献   

8.
9.
10.
In this study, we successfully assembled the complete mitochondrial genome of the Amu Darya sturgeon Pseudoscaphirhynchus kaufmanni. Based on this mitochondrial genome and previously published mitochondrial genomes of members of the Acipenseridae family, we assessed the phylogenetic position of P. kaufmanni using maximum likelihood and Bayesian inference for phylogeny reconstruction. The resultant phylogenetic trees were well-resolved, with congruence between different phylogenetic methods. This robust phylogenetic analysis elucidated the relationship among the four acipenserid genera and strongly supported the division of the family into three main clades. Evaluation of molecular phylogeny using maximum likelihood and Bayesian analysis led to the following conclusions: (a) the most basal position within the Acipenseridae remains in the clade containing Acipenser oxyrinchus and Acipenser sturio; (b) the genus Scaphirhynchus belongs to the Atlantic clade and is a sister group of the remaining species of the clade; and (c) the close relationship between P. kaufmanni and Acipenser stellatus is well supported.  相似文献   

11.
12.
Taxonomy of phyllophoroid algae: the implications of life history   总被引:1,自引:1,他引:0  
Maggs  Christine A. 《Hydrobiologia》1990,204(1):119-124
The Phyllophoraceae Rabenhorst (Gigartinales) is a family that shows a great diversity of life history patterns. The three largest phyllophoroid genera, Ahnfeltia, Gymnogongrus and Phyllophora, all commercial sources of phycocolloids, show the greatest range of life history. Information from life history studies has been of significance to classification of the Phyllophoraceae at the family, generic and specific levels. In the tetrasporophyte of Ahnfeltia plicata, previously known as Porphyrodiscus simulans, tetrasporangia are zonate and borne terminally in small superficial sori in contrast to the chains of cruciate tetrasporangia characteristic of the Phyllophoraceae. A study of reproduction and life history in the type species, A. plicata, from the Atlantic concluded that the unique carposporophyte development, in conjunction with the most primitive pit-plug structure known in the Florideophycidae, justified the proposal of a new family Ahnfeltiaceae Maggs et Pueschel in the Ahnfeltiales Maggs et Pueschel. Most Pacific species of Ahnfeltia are instead phyllophoracean and closely related to Gymnogongrus. Gymnogongrus griffithsiae, the type species, forms tetrasporoblasts whereas the majority form internal cystocarps and have heteromorphic life histories. Proposals to divide the genus by life history type require further detailed morphological and ontogenetic studies of G. griffithsiae. Phyllophora species exhibit at least three different types of life history, tetrasporoblastic, isomorphic and heteromorphic, and this genus could likewise be split along these lines. At the specific level, intraspecific life history variability appears to be related to morphological variation in some species of Gymnogongrus.  相似文献   

13.
The genus Balechina (=subgenus Pachydinium) was established for heterotrophic gymnodinioid dinoflagellates with a thick cell covering. The type species, B. pachydermata (=Gymnodinium pachyderm‐atum), showed numerous fine longitudinal striae, whereas B. coerulea (=G. coeruleum) showed ~24 prominent longitudinal surface ridges or furrows and a distinctive blue pigmentation. We have investigated the morphology and molecular phylogeny of these taxa and the species Gymnodinium cucumis, G. lira and G. amphora from the western Mediterranean, Brazil and Japan. Sudden contractions at the cingulum level were seen in B. pachydermata, which also showed a high morphological variability which included morphotypes that have been described as Amphidinium vasculum, G. amphora, G. dogielii and G. gracile sensu Kofoid and Swezy. Molecular phylogeny based on small subunit rRNA gene sequences revealed that Balechina coerulea, G. cucumis and G. lira formed a clade distantly related to the clade of the type species, B. pachydermata, and G. amphora. We propose the new genus Cucumeridinium for the species with longitudinal ridges and a circular apical groove (Cucumeridinium coeruleum comb. nov., C. lira comb. nov. and C. cucumis comb. nov.), and Gymnodinium canus and G. costatum are considered synonyms of C. coeruleum. The genus Balechina remains for the species with a double‐layer cell covering, bossed surface with fine striae, and an elongated elliptical apical groove. At present, the genus is monotypic containing only B. pachydermata.  相似文献   

14.
Previous studies have established that the 5′ end of the mitochondrial gene COI (cytochrome oxidase subunit I) is useful for rapid and reliable identification of red algal species and have demonstrated that our understanding of red algal biodiversity and biogeography is fragmentary. In this context, we are completing a thorough sampling along the Canadian coast and using the DNA barcode for the assignment of collections to genetic species to explore algal diversity in the Canadian flora. In the present study, we provide results regarding diversity of members of the red algal family Phyllophoraceae. We have analyzed 354 individuals from the Arctic, Atlantic, and Pacific coasts of Canada, as well as 26 specimens from the USA, Europe, and Australia, resolving 29 species based on the analyses of the DNA barcode. Twenty‐three of these genetic species were present in Canada where only 18 species are currently recognized, including Ceratocolax hartzii Rosenv., which was in the same genetic species group as its host Coccotylus truncatus (Pall.) M. J. Wynne et N. J. Heine and is thus transferred to Coccotylus, C. hartzii (Rosenv.) comb. nov., but retained as a distinct species owing to its unique habit and phenology. Our results revealed the presence of cryptic diversity within the genera Coccotylus, Mastocarpus, Ozophora, and Stenogramme, for which we resurrect Coccotylus brodiei (Turner) Kütz. and describe Mastocarpus pachenicus sp. nov., Ozophora lanceolata sp. nov., and Stenogramme bamfieldiensis sp. nov., leaving a multitude of unnamed Mastocarpus spp. in need of further taxonomic study. In addition, we report range extensions into British Columbia of Besa papillaeformis Setch., previously known only from its type and nearby localities in California; Gymnogongrus crenulatus (Turner) J. Agardh, recorded only from the Atlantic; and Stenogramme cf. rhodymenioides Joly et Alveal, previously only known from South America. Finally, the phylogenetic affinities of the Canadian species of Phyllophoraceae characterized in this study were investigated using LSU rDNA, RUBISCO LSU (rbcL), and combined analyses.  相似文献   

15.
A phylogeny of the genus Aphis Linnaeus, 1 758 was built primarily from specimens collected in the Midwest of the United States. A data matrix was constructed with 68 species and 41 morphological characters with respective character states of alate and apterous viviparous females. Dendrogram topologies of analyses performed using UPGMA (Unweighted Pair Group Method with Arithmetic Mean), Maximum Parsimony and Bayesian analysis of Cytochrome Oxidase I, Elongation Factor 1‐α and primary endosymbiont Buchnera aphidicola 16S sequences were not congruent. Bayesian analysis strongly supported most terminal nodes of the phylogenetic trees. The phylogeny was strongly supported by EF1‐α, and analysis of COI and EF1‐α molecular data combined with morphological characters. It was not supported by single analysis of COI or Buchnera aphidicola 16S. Results from the Bayesian phylogeny show 4 main species groups: asclepiadis, fabae, gossypii, and middletonii. Results place Aphis and species of the genera Protaphis Börner, 1952, Toxoptera Koch, 1856 and Xerobion Nevsky, 1928 in a monophyletic clade. Morphological characters support this monophyly as well. The phylogeny shows that the monophyletic clade of the North American middletonii species group belong to the genus Protaphis: P. debilicornis (Gillette & Palmer, 1929 ), comb. nov., P. echinaceae (Lagos and Voegtlin, 2009 ), comb. nov., and P. middletonii (Thomas, 1879 ). The genus Toxoptera should be considered a subgenus of Aphis (stat. nov.). The analysis also indicates that the current genus Iowana Frison, 1954 should be considered a subgenus of Aphis (stat. nov.).  相似文献   

16.
South Korean species of the genus Eusterinx Förster are reviewed here. Nine species of the genus Eusterinx are found to occur in South Korea, and five species, Eusterinx (E.) elongata sp. nov. , E. (Holomeristus) hirtis sp. nov. , E. (Ischyracis) fulvipes sp. nov. , E. (I.) petiolata sp. nov. and E. (I.) rufithorax sp. nov. , are described. Four more species of Eusterinx from subgenera Divinatrix, Eusterinx and Holomeristus are recorded from South Korea for the first time. Hitherto, unknown male of the Eastern Palaearctic species E. (Divinatrix) kurilensis Humala is described. A key to all known species of the genus Eusterinx occurring in South Korea is provided.  相似文献   

17.
Jeon, M.‐J., Song, J.‐H. & Ahn, K.‐J. (2012). Molecular phylogeny of the marine littoral genus Cafius (Coleoptera: Staphylinidae: Staphylininae) and implications for classification. —Zoologica Scripta, 41, 150–159. A phylogenetic analysis of the marine littoral genus Cafius Stephens is presented based on molecular characters. The data set comprised partial mitochondrial COI (910 bp), COII (369 bp), 12S rDNA (351–354 bp), 16S rDNA (505–509 bp) and nearly complete sequences of 18S rDNA (1814–1830 bp) for 37 species. Twenty‐seven Cafius species, representing five of six subgenera, two Remus Holme species, three Phucobius Sharp species, monotypic Thinocafius Steel and four outgroups were included. The sequences were analysed simultaneously by parsimony analysis in Tree Analysis Using New Technology (TNT) with traditional manual alignment, direct optimization (DO) in the program POY4 under a variety of gap costs and partitioned Bayesian analysis for the combined data. The genus Cafius and nearly all of its subgenera were not supported as being monophyletic. Instead, all analyses (parsimony trees, DO tree under equal weighting and Bayesian tree) showed monophyly of Cafius + Phucobius + Remus + Thinocafius (clade Z) and all seven nested clades (A–G). However, the phylogenetic relationships among clades A–G differed among the analyses. The genus Phucobius was recovered as a monophyletic group within Cafius. The genus Remus was not monophyletic but formed a clade with C. rufescens Sharp and C. rufifrons Bierig within Cafius. The genus Thinocafius formed a clade with C. caviceps Broun, C. litoreus (Broun) and C. quadriimpressus (White) within Cafius. We propose new concepts for the genus Cafius and its related genera, and the seven nested clades.  相似文献   

18.
As part of our ongoing phylogenetic study of genusHypericum, nuclear ribosomal DNA internal transcribed spacer sequences were analyzed for 36 species ofHypericum as ingroup and two species ofThornea as outgroup. This sampling included most of the previously described species from both Korea and Japan. The ITS phylogeny suggested that the surveyedHypericum species belong to a monophyletic section,Trigynobrathys, and a polyphyletic section,Hypericum. In addition, two monotypic sections,Sampsonia andRoscyna, were identified. Members of sectionHypericum occur in four different lineages worldwide, which imply at least four independent origins. The Korean and Japanese species of sectionHypericum form a monophyletic group, except forH. vulcanicum. Instead, that particular species belongs to a distinct monophyletic group withH. scoreri andH. formosa from other geographic areas, and is a sister to sectionTrigynobrathys. The Korean and Japanese species of sectionTrigynobrathys show a monophyletic origin.H. sampsonii is now recognized as a distinct section rather than being a member of sectionsHypericum orDrosocarpium, as had been indicated previously. Our results differ somewhat from those of recent morphological and cytological studies. The phylogenetic relationships among Korean and Japanese species have now been mostly resolved via ITS phylogeny.  相似文献   

19.
Based on morphological characteristics and molecular phylogeny, we reclassified Cordyceps cuboidea and allied species C. alboperitheciata, C. prolifica, and Ophiocordyceps ryogamiensis. We investigated their teleomorph-anamorph relationships and revealed that these four species have Hirsutella-like anamorphs with morphological differences between them. By analyzing their molecular phylogeny, inferred from DNA sequences of internal transcribed spacer (ITS) and large subunit (LSU) D1/D2 region of rDNA, they were separated into four close-knit clades. Although C. prolifica and O. ryogamiensis formed their own clades, isolates of C. cuboidea separated into two clades, i.e., a true C. cuboidea clade and one resembling a new species, the O. paracuboidea clade. The latter two species are distinguished by the fruiting region of the stroma. In addition, C. alboperitheciata is regarded as a synonym of C. cuboidea. From the morphology, teleomorph-anamorph relationships, and molecular phylogeny, we concluded these species should be assigned to the genus Ophiocordyceps.  相似文献   

20.
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