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1.
Three new species ofMycogloea are described and illustrated; they are:M. amethystina from Canada,M. nipponica, from Japan, andM. bullata from Thailand.Mycogloea tahitiensis is reported from Japan and additional undescribed taxa in the genus are briefly noted. Some characteristics of the genus are discussed, and a key is provided for six species recognized at this time.  相似文献   

2.
Jozef Somogyi 《Biologia》2006,61(4):381-385
Taxonomic, nomenclatural and chorological notes on several taxa of the genus Echinodorus are given. A new species E. maculatus is described. The name Alisma intermedium (basionym of the name E. intermedius) is lectotypified. Echinodorus major and E. martii should be treated as two distinct taxa. The name E. xinguensis was invalidly published. It is also confirmed that E. africanus, E. veronikae and E. viridis (all belonging to the E. uruguayensis group) do not originate from Africa. The name E. bleherae should be written with a female suffix (-ae); this name is considered here as a synonym of the earlier name E. grisebachii.  相似文献   

3.
The systematics and taxonomy of North Americancyprinid fishes has historically been said tobe in a chaotic state of affairs. Much of theconfusion as to relationships of species restsin the lack of explicit phylogenetic hypothesesof species and reliance upon degree ofdistinctiveness of taxa or their overallsimilarity for generic placement. Some specieshave had more turbulent or variable taxonomichistories than others. The ornate shiner, Cyprinella ornata, is one of those species,having been placed in the genera Notropis,Codoma, and Cyprinella within the last20 years and found in current texts in any ofthese three genera. Most of the confusionregarding placement of this species has beenrelated to lack of explicit phylogenetichypotheses to formulate its classification, butto a certain degree some researchers haveignored phylogenetic studies and preferred torely upon its morphological distinctiveness orreproductive behavioral traits of questionablehomology to place it in a monotypic genus andalign it with the genera Pimephales andOpsopoeodus.I present a phylogenetic analysis based oncomplete Cytochrome b sequences fromornate shiners, other species of Cyprinella, purported relatives, and severalother species of the Shiner Clade to determinethe phylogenetic affinities of this enigmaticspecies. Molecular analysis reveals the ornateshiner to be more closely related to species ofCyprinella than to a Pimephalesplus Opsopoeodus clade as previouslydiscussed in one morphological analysis, or asargued by Page and Johnston (1990), Johnstonand Page (1992) and Page and Ceas (1989) basedon observations of spawning behaviors andhypotheses of homology between crevice-spawningand egg-clumping behaviors. This molecularanalysis is more consistent with earliermorphological phylogenetic hypotheses of Mayden(1989) wherein these two clades are notconsidered to be closely related and the ornateshiner is a member of the genus Cyprinella.  相似文献   

4.
In the present study phylogenetic relationships of the genus Stereocaulon (lichenized ascomycetes) were examined using DNA sequences from the ITS1–5.8 S–ITS2 rDNA gene cluster and from the protein-coding β-tubulin gene. In addition to the fruticose species traditionally classified in Stereocaulon, representatives of the crustose species that have recently been transferred to the genus were included. Muhria, a monotypic genus that is morphologically similar to Stereocaulon, differing only in apothecia ontogeny, was also incorporated. The analyses included 101 specimens from the ingroup representing 49 taxa. Sequences from both DNA regions were analysed simultaneously using direct optimization under the parsimony optimality criterion. The results support the inclusion of the crustose species and Muhria in Stereocaulon, while the current infrageneric classification is not supported. As Muhria is securely nested within Stereocaulon the new combination Stereocaulon urceolatum comb. nov. (syn. Muhria urceolata) is made. Further, species concepts need to be re-examined, as some species do not appear as monophyletic entities in the phylogeny.  相似文献   

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7.
The relationship between Litsea and related genera is currently unclear. Previous molecular studies on these taxa using cpDNA and nrITS were unable to produce well-resolved phylogenetic trees. In this study, we explored the potential of the rpb2 gene as a source of molecular information to better resolve the phylogenetic analysis. Although rpb2 was believed to be a single-copy gene, our cloning results showed that most species examined possessed several copies of these sequences. However, the genetic distance among copies from any one species was low, and these copies always formed monophyletic groups in our molecular trees. Our phylogenetic analyses of rpb2 data resulted in better resolved tree topologies compared to those based on cpDNA or nrITS data. Our results show that monophyly of the genus Litsea is supported only for section Litsea. As a genus, Litsea was shown to be polyphyletic. The genera Actinodaphne and Neolitsea were resolved as monophyletic groups in all analyses. They were also shown to be sisters and closer to the genus Lindera than to the genus Litsea. Our results also revealed that the genus Lindera is not a monophyletic group.  相似文献   

8.
The genus Dermanyssus is currently composed of 24 hematophagous mite species and includes the Poultry Red Mite, Dermanyssus gallinae, a serious pest in poultry houses. Morphologically, Dermanyssus species fall into two groups corresponding to Moss’ gallinae-group and to hirsutus-group + Microdermanyssus. Species of the gallinae-group exhibit high levels of morphological variability, and are nearly impossible to distinguish. Species of the second group display consistent characters and host associations and are easily distinguishable. Species of the gallinae-group tend to be the major problems in poultry houses and it is unknown whether D. gallinae is the only pest, or if there are numerous cryptic species present in the system.Twenty species of Dermanyssus were tested phylogenetically based on 46 morphological characters. A subset of species, mainly of the gallinae-group, represented each by several populations, was sequenced for two mitochondrial and one nuclear gene regions. This allowed testing their specific status and their interrelationships based and on morphological and molecular characters. The molecular data was analysed separately and in combination with morphological characters. As expected, morphology did a poor job resolving relationships.Molecular data proved more informative. The resulting phylogenetic hypotheses brought some information about interrelationships among species of the gallinae-group showing a split into two main clades. The invasion of human managed environments seems to occur only in taxa within one of the two clades. The host spectrum seems to get enlarged in more derived taxa in the same clade. A delineation of six species within the gallinae-group is provided. Additionally, a key for morphological identification of these species is provided. D. gallinae appears to be the only pest in poultry houses, but is composed of several different and more or less strongly isolated lineages. A new species found from the black swift is described.  相似文献   

9.
报道了中国黄枝衣科(Teloschistaceae)的一中国新记录属粉黄衣属(新拟)(Xanthomendoza)和一中国新记录种漫粉黄衣(新拟)(Xanthomendoza ulophyllodes)及石黄衣属(Xanthoria)的一新记录种裂芽黄衣(新拟)(Xanthoria calcicola)。对漫粉黄衣的ITS序列进行了测定和系统发育分析,并对相关类群的形态和分子数据进行了讨论。对2新记录种的形态特征、生境与分布进行了详细描述,并提供了形态特征图。  相似文献   

10.
Seven isolates ofTorulomyces from Asian and Australian soil samples were studied in comparison with known taxa of the genus and withMonocillium indicum, the type species ofMonocillium. Three new species,Torulomyces parviverrucosus, T. laevis, andT. ovatus, are described, andT. brunneus is described as a new combination. Conidial characteristics, especially their shape and surface structure, are useful taxonomic criteria for distinguishing species ofTorulomyces. Monocillium is considered to be a distinct genus.  相似文献   

11.
Summary  The new species Cibirhiza spiculata Thulin & Goyder, from Acacia-Commiphora bushland on sand in the Somali National Regional State (Ogaden) of Ethiopia, is described and illustrated. Its conservation status has been assessed. A molecular phylogenetic analysis confirms its placement in the tribe Fockeeae and indicates a position of the new species as sister to C. albersiana. The almost obsolete anther appendages, the outer corona with spreading lobes, as well as the pollinia with apparently single pollen grains, also support its placement in Cibirhiza. However, C. spiculata differs markedly from both previously known species of this genus (C. dhofarensis in Oman and Yemen and C. albersiana in Tanzania and Zambia) by its narrowly linear, subsessile leaves and by the inner corona lobes that are curved inwards over the gynostegium and each ending in a spinulose head.  相似文献   

12.
Electrophoretic examination of variousPinus species from both subgenera revealed that several taxa differ in the number of loci that control the enzyme system 6-phosphogluconate dehydrogenase (6PGDH). Based on inheritance analyses and published data, it was established that all species of subg.Pinus possess only two 6PGDH loci, whereas all stone pines of subg.Strobus exhibit four controlling loci. In order to trace the phylogenetic links at which one or two gene duplications occurred during pine evolution, several species of subsect.Strobi (sectionStrobus) and two species of sect.Parrya were additionally investigated. Based on conclusions about the uniqueness of gene duplications and the different numbers of 6PGDH loci, a phylogenetic tree of the pine taxa was constructed. This tree shows some new features not recognized in earlier studies and supports several novel assignments postulated in very recent pine classifications.  相似文献   

13.
The satellite DNA Msat-160 has been previously characterized in several species of the genus Microtus. Here we present the characterization of Msat-160 from Chionomys nivalis, a species with a very primitive karyotype. As in other Microtus species analyzed, C. nivalis Msat-160 is AT rich, has a monomer length of 160 bp, is undermethylated and is mainly located in all the pericentromeric heterochromatin of all autosomes and the X chromosome, but is completely absent from the Y chromosome. Hence, our results support the hypothesis that Msat-160 was initially distributed in the pericentromeric heterochromatin of all autosomes and the X chromosome. The taxonomic status of the genus Chionomys in relation to the genus Microtus is a very interesting issue, so we constructed phylogenetic dendrograms using Msat-160 sequences from several Microtus species. Although the results were not informative about this issue, the presence of Msat-160 in C. nivalis and Microtus species suggested that both genera are closely related and that this satellite DNA was present in the common ancestor. Studies of Msat-160 in different arvicoline species could help to determine the origin of this satellite and, perhaps, to establish the phylogenetic relationships of some arvicoline groups.  相似文献   

14.
Summary  Taxonomic and phylogenetic studies of the Neotropical genus Lophostachys showed that it is congeneric with Lepidagathis. The following new combinations of species previously described under Lophostachys are proposed: Lepidagathis chiapensis (Acosta) Kameyama, L. cyanea (Leonard) Kameyama, L. guatemalensis (Donn. Sm.) Kameyama, L. laxifolia (Nees) Kameyama, L. montana (Nees) Kameyama, L. nemoralis (Mart. ex Nees) Kameyama, L. soconuscana (T. F. Daniel) Kameyama, and L. uxpanapensis (Acosta) Kameyama. Five new species are described: Lepidagathis callistachys, L. cuneiformis, L. meridionalis, L. paraensis and L. wasshausenii. Three lectotypes are also designated. A key to the Neotropical secundiflorous species is provided.  相似文献   

15.
As part of systematic studies of the genus Porphyrain New Zealand, constituent sugar analyses of cell wall polysaccharidesin situ in dry thalli were found to yield data that weretaxonomically informative. Variation in constituent sugar levels betweenspecieswas sufficient in some cases to be useful in species differentiation. Thereproductive state of thallus regions had a significant impact on the levels ofconstituent sugars, whereas storage of dried thalli for eight months had noeffect. Three epiphytic taxa currently classified as species ofPorphyra appear to be incorrectly placed within the genus,as their constituent sugars and the levels of these sugars differed markedlyfrom those of all other species examined.  相似文献   

16.
Hongeo gen. nov. is proposed following examinations of several individuals, including adult males, of the type species Raja koreana, previously described from a single adult female specimen from the southern coast of the Korean Peninsula. A number of external (including claspers, squamation, and ampullary and lateral line canal systems) and skeletal characters are newly described. The phylogenetic position of R. koreana among 26 nominal rajid supraspecific taxa plus 2 unnamed supraspecific taxa of Rajidae and 3 outgroups was estimated. According to a strict consensus tree of 20 equally parsimonious trees of 139 steps (CI = 0.626; RI = 0.850; RC = 0.532; HI = 0.374), Hongeo gen. nov. is defined by the two derived character states: rostral cartilage continuous with neurocranium and stout proximally, but very slender and uncalcified distally; and anterior fontanelle broad, extending forward onto the basal part of rostral cartilage slightly beyond the leading edge of nasal capsules. The new genus also differs from all other supraspecific taxa of Rajidae in the following combination of characters: dorsal surface of tail with a row of distinct thorns along midline in both sexes; most thorns directed anteriorly; a pair of longitudinally elongated black blotches having undulated contours on middle of dorsal surface of disc; three groups of outer buccal ampullae and tubules; three groups of nasal ampullae and tubules; hyoidean ampullae and tubules on ventral surface posteriorly extending past cloaca; rostral shaft narrow with filamentous cartilage at base; scapulocoracoid comparatively short and high with dorsoventrally elliptical anterior fenestra and expanded postventral fenestra; external margin of mesopterygium of pectoral fin slightly undulated, not sinuous, and not fused with pectoral radials; and clasper component eperon and pent present.  相似文献   

17.
Three new species of Candida and a new combination in the genus Hyphopichia are proposed from phylogenetic analysis of nucleotide divergence in domains D1/D2 of the large subunit (26S) rDNA. The new taxa and their type strains are the following: Candida bentonensis sp. nov. (NRRL YB-2364, CBS 9994), Candida hispaniensis sp. nov. (NRRL Y-5580, CBS 9996), Candida pseudorhagii sp. nov. (NRRL YB-2076, CBS 9998) and Hyphopichia heimii comb. nov. (NRRL Y-7502, CBS 6139), basionym Pichia heimii Pignal. Phylogenetic analysis placed C. pseudorhagii and H. heimii in the Hyphopichia clade whereas C. bentonensis and C. hispaniensis are members of the Yarrowia clade.  相似文献   

18.
Based on the results of morphological and DNA sequence (partial D1–D3/D7–D8 nuLSU and partial nuSSU-ITS1-5.8S rDNA) data, three species of Plasmopara are revised and reclassified. A species of Plasmopara parasitic on Scorzonera, invalidly published several times, is assigned to a new genus and species under Novotelnova scorzonerae. Plasmopara euphrasiae sp. nov. is segregated from P. densa, and P. centaureae-mollis is revised and relegated to synonymy of Bremia centaureae. All taxa are described and illustrated.  相似文献   

19.
Two new species of hyphomycetes,Xenocylindrocladium guianense andX. subverticillatum, are described from plant debris collected in French Guiana and Singapore, respectively. The genusXenocylindrocladium has thus far been known from one species,X. serpens, which was described from plant debris collected in Ecuador. The two new taxa are compared with and distinguished fromX. serpens based on morphology, cultural characteristics and phylogenetic analysis of DNA sequence data of the 5.8S rDNA with flanking ITS1 and ITS2 regions and the 5′ end of the β-tubulin gene. These species are also compared with other closely related hypocrealean taxa. Present collection data suggest that species ofXenocylindrocladium could be restricted to the tropics.  相似文献   

20.
Gnomonia fragariae is a poorly studied ascomycete belonging to Diaporthales. Originally G. fragariae was considered a saprophyte occurring on dead tissues of strawberry plants. Recently this fungus was found in Latvia and Sweden, and it was proven to be the cause of severe root rot and petiole blight of strawberry. Thirteen isolates of this pathogen and several other Gnomonia species occurring on rosaceous hosts were characterized by molecular analysis using nucleotide sequences of partial LSU rRNA gene and the total ITS region. The homologous regions from relevant diaporthalean taxa available in the GenBank were also included and compared with the taxa sequenced in this study. Phylogenetic analyses revealed that G. fragariae, G. rubi, and Gnomonia sp. (CBS 850.79) were genetically different from G. gnomon, the type species of the genus, and other members of Gnomoniaceae. The analyses showed that G. fragariae and Hapalocystis were genetically very closely related, forming a phylogenetic clade, which is possibly presenting a new family in the Diaporthales. Morphological comparisons of the Gnomonia species on the basis of commonly used criteria for the taxonomy of Diaporthales, so far did not reveal any evident features for the polyphyletic status of Gnomonia.  相似文献   

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