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1.
Three new species of Agaricales are described and illustrated from eastern Honshu, Japan:Boletus rhodocarpus sp. nov. (sectionLuridi), forming large, deep red basidiomata with a pileus covered with small, blackish brown scales, was found on ground in a highland forest dominated byTsuga diversifolia andAbies veitchii; Phaeomarasmius laccarioides sp. nov. (subgenusCarpophilus), forming a squamulose-fibrillose, reddish brown pileus in which the pileipellis consists of chains of thick-walled sphaerocysts with heavily incrusting, brown pigment, was found on a fallen fruit ofLiquidambar styraciflua; Pluteus phaeocephalus sp. nov. (subsectionHispidodermini of sectionCelluloderma), forming a dark brown, velvety pileus and a white stipe densely covered with dark brown punctate scales, was found on dead fallen twigs ofQuercus serrata.  相似文献   

2.
The wall of mature ascospores ofSaccharomyces cerevisiae showed in sections under the electron microscope a dark outer layer and a lighter inner layer. The latter was composed of a greyish inner part and a light outer part. During germination, the spore grew out at one side and the dark outer layer was broken. Of the light inner layer, the inner greyish part became the wall of the vegetative cell, but the extented part of the cell had a new wall.  相似文献   

3.
A new species of mudskipper,Periophthalmus spilotus, is described on the basis of 16 specimens from Sumatra, Indonesia. It differs from other species ofPeriophthalmus by the following combination of characters: pelvic fins totally united into rounded disk; first dorsal fin high, greyish, no spots on fin nor elongate spines; second dorsal fin typically with 14 total elements; anal fin typically with either 14 or 15 total elements; length of anal-fin base 21.8–29.0% SL; and length of second dorsal-fin base 22.5–26.7% SL. This species is most similar to, and probably most closely related to,P. chrysospilos.  相似文献   

4.
Likolampi is a small groundwater kettle-hole lake in Ilomantsi, Eastern Finland. At 11 m water depth the uppermost 51 cm of sediment contains about 390 varves. A thin layer of chrysophyte statospores is the main structural unit in these; in some varves it is followed by a layer of cf. Drepanocladus fluitans moss spores. Below the laminated sequence, two layers of moss detritus (110–87 cm, 81–51 cm) alternate with greyish brown fine detritus. Pollen analysis reveals that the start of the deposition of varved sediment coincides with the beginning of intensive fiber plant retting with large quantities of Cannabis/Humulus -type pollen and even regular occurrence of the insect-pollinated Linum usitatissimum. The cf. Drepanocladus spores are almost absent during the retting period (c. 1590–1900 by the varves), but very common before and after it. Drepanocladus fluitans is capable of assimilating dissolved CO2 in water, so it thrives at low pH and is typical for oligotrophic clear-water lakes. We conclude that the stratigraphy of Drepanocladus fragments and spores is a true negative indicator of cultural influence in Likolampi.  相似文献   

5.
6.
Thiothrix nivea grows profusely in tufts of greyish white material on pebbles in a local sulfide spring. The spring remained a constant 10.8° C during the course of the study. Chemical analyses indicated that the spring water contained 0.27 mg/l sulfide, 0.37 mg/l oxygen, and 0.77 mg/l dissolved organic carbon. Tufts ofThiothrix growth were removed from the pebbles and examined by phase and electron microscopy. The cell filaments contained numerous sulfur granules which disappeared upon incubation in the refrigerator. The average cell diameter was 1.5 m and the length 4.0 m. When cells were lysed by hyperplasmolysis a sheath was readily discernible. The presence of a sheath, 60 nm thick, was confirmed in thin sections. Fine structure analysis also revealed that the organism was a gram negative bacterium. Sulfur granules were bound by a unit membrane extending from the cytoplasmic membrane.Thiothrix nivea was grown for short periods of time in slide culture. In some cases the filaments fragmented into short segments ca 15m long. These may represent gonidia as initially reported by Winogradsky.  相似文献   

7.
A molecular phylogeny of Hebeloma species from Europe   总被引:2,自引:1,他引:1  
In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.  相似文献   

8.
The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.  相似文献   

9.
10.
The family Sordariaceae incorporates a number of fungi that are excellent model organisms for various biological, biochemical, ecological, genetic and evolutionary studies. To determine the evolutionary relationships within this group and their respective phylogenetic placements, multiple-gene sequences (partial nuclear 28S ribosomal DNA, nuclear ITS ribosomal DNA and partial nuclear β-tubulin) were analysed using maximum parsimony and Bayesian analyses. Analyses of different gene datasets were performed individually and then combined to generate phylogenies. We report that Sordariaceae, with the exclusion Apodus and Diplogelasinospora, is a monophyletic group. Apodus and Diplogelasinospora are related to Lasiosphaeriaceae. Multiple gene analyses suggest that the spore sheath is not a phylogenetically significant character to segregate Asordaria from Sordaria. Smooth-spored Sordaria species (including so-called Asordaria species) constitute a natural group. Asordaria is therefore congeneric with Sordaria. Anixiella species nested among Gelasinospora species, providing further evidence that non-ostiolate ascomata have evolved from ostiolate ascomata on several independent occasions. This study agrees with previous studies that show heterothallic Neurospora species to be monophyletic, but that homothallic ones may have a multiple origins. Although Gelasinospora and Neurospora are closely related and not resolved as monophyletic groups, there is insufficient evidence to place currently accepted Gelasinospora and Neurospora species into the same genus.  相似文献   

11.
Phylogenetic relationships within the angiosperm orderCampanulales were investigated by comparative sequencing of the chloroplast generbcL. CompleterbcL sequences were obtained for ten species in six families within the order. These data were analyzed along with previously publishedrbcL sequences from other taxa (for a total of 117 species) within the subclassAsteridae and outgroups, producing 32 equally parsimonious trees. A subset consisting of 44 of these taxa was then chosen and more rigorous analyses performed, resulting in four equally parsimonious trees. Results indicate that two major clades roughly corresponding to traditionally circumscribedAsterales andCampanulales exist as sister taxa. In particular, therbcL trees indicate thatSphenoclea is not a member ofCampanulales orAsterales, thatPentaphragma is more closely allied toAsterales thanCampanulales, that theCyphiaceae are not monophyletic, thatCampanulaceae andLobeliaceae are not sister taxa, and thatStylidiaceae are correctly placed withinCampanulales.  相似文献   

12.
Truffle trouble: what happened to the Tuberales?   总被引:1,自引:1,他引:0  
An overview of truffles (now considered to belong in the Pezizales, but formerly treated in the Tuberales) is presented, including a discussion on morphological and biological traits characterizing this form group. Accepted genera are listed and discussed according to a system based on molecular results combined with morphological characters. Phylogenetic analyses of LSU rDNA sequences from 55 hypogeous and 139 epigeous taxa of Pezizales were performed to examine their relationships. Parsimony, ML, and Bayesian analyses of these sequences indicate that the truffles studied represent at least 15 independent lineages within the Pezizales. Sequences from hypogeous representatives referred to the following families and genera were analysed: DiscinaceaeMorchellaceae (Fischerula, Hydnotrya, Leucangium), Helvellaceae (Balsamia and Barssia), Pezizaceae (Amylascus, Cazia, Eremiomyces, Hydnotryopsis, Kaliharituber, Mattirolomyces, Pachyphloeus, Peziza, Ruhlandiella, Stephensia, Terfezia, and Tirmania), Pyronemataceae (Genea, Geopora, Paurocotylis, and Stephensia) and Tuberaceae (Choiromyces, Dingleya, Labyrinthomyces, Reddellomyces, and Tuber). The different types of hypogeous ascomata were found within most major evolutionary lines often nesting close to apothecial species. Although the Pezizaceae traditionally have been defined mainly on the presence of amyloid reactions of the ascus wall several truffles appear to have lost this character. The value of the number of nuclei in mature ascospores as a delimiting family character is evaluated and found to be more variable than generally assumed.  相似文献   

13.
The serological reaction of seed proteins provides evidence for a partly new systematic arrangement ofCytisus sect.Trianthocytisus and ofCytisus s.l. Proposed modifications agree with recent advances in morphological taxonomy. Sect.Trianthocytisus includes only two species,C. villosus andC. aeolicus. Its position is central within the genus, and this fact agrees with the proposed retypification ofCytisus (type species:C. villosus).C. emeriflorus, formerly included in the same section, constitutes the monospecific sect.Emeroides, which is intermediate towards the genusLembotropis. This is serologically isolated and includes onlyL. nigricans. It is confirmed thatC. sessilifolius should be removed from the genusCytisus as a monospecific genus:Cytisophyllum Lang which is closely allied toHesperolaburnum and toPodocytisus, the most primitive genera ofGenisteae.  相似文献   

14.
The genusKarschia, in the earlier sense, including saprophytes and parasites on lichens, has been thought to be a non-lichenized parallel genus of the lichen genusBuellia. Modern workers included it on the one hand inBuellia, on the other hand combined it with bitunicate ascomycetes. It is now proved thatKarschia is heterogeneous and contains but superficially similar members both of the genusBuellia of theLecanorales and of typical or masked bitunicateAscomycetes. Therefore, it can not be regarded as a link betweenLecanorales andDothideales. The type species ofKarschia belongs to theDothideales.
  相似文献   

15.
Parsimony analyses of the internal transcribed spacer regions of nuclear ribosomal DNA (ITS 1 & ITS 2) for 38 taxa sampled from the Phebalium group (Rutaceae: Boronieae) and two outgroups confirm that, with the exception of Phebalium sensu stricto and Rhadinothamnus, six of the currently recognised genera within the group are monophyletic. The data indicate that Phebaliums. str. is paraphyletic with respect to Microcybe, and Rhadinothamnus is paraphyletic with respect to Chorilaena. Rhadinothamnus and Chorilaena together are the sister group to Nematolepis. Drummondita, included as an outgroup taxon, clustered within the ingroup as sister to Muiriantha and related to Asterolasia.The phylogeny suggests that the evolution of major clades within a number of these genera (e.g. Phebalium) relates to vicariance events between eastern and south-western Australia. Leionema is an eastern genus, with the most basal taxon being the morphologically distinct Leionema ellipticum from northern Queensland. Leionema also includes one species from New Zealand, but this species (as with some others) proved difficult to sequence and its phylogenetic position remains unknown. Taxonomic changes at the generic level are recommended.The authors wish to thank Paul G.Wilson, PERTH, for advice and discussion, and Paul Forster, BRI, for collecting and providing material of Leionema ellipticum. The project was supported by a Melbourne University Postgraduate Award (to BM), the Australian Biological Resources Study (ABRS), Australian Systematic Botany Society and Wolf Den (Australia) Investments.  相似文献   

16.
17.
Transformation with the Arabidopsis bHLH gene 35S:GLABRA3 (GL3) produced novel B. napus plants with an extremely dense coverage of trichomes on seedling tissues (stems and young leaves). In contrast, trichomes were strongly induced in seedling stems and moderately induced in leaves of a hairy, purple phenotype transformed with a 2.2 kb allele of the maize anthocyanin regulator LEAF COLOUR (Lc), but only weakly induced by BOOSTER (B-Peru), the maize Lc 2.4 kb allele, or the Arabidopsis trichome MYB gene GLABRA1 (GL1). B. napus plants containing only the GL3 transgene had a greater proportion of trichomes on the adaxial leaf surface, whereas all other plant types had a greater proportion on the abaxial surface. Progeny of crosses between GL3+ and GL1+ plants resulted in trichome densities intermediate between a single-insertion GL3+ plant and a double-insertion GL3+ plant. None of the transformations stimulated trichomes on Brassica cotyledons or on non-seedling tissues. A small portion of bHLH gene-induced trichomes had a swollen terminal structure. The results suggest that trichome development in B. napus may be regulated differently from Arabidopsis. They also imply that insertion of GL3 into Brassica species under a tissue-specific promoter has strong potential for developing insect-resistant crop plants. Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.  相似文献   

18.
seventeen new species and combinations are proposed in the generaChondrorhyncha, Cischweinfia, Cochlioda, Eloyella, Encyclia, Kefersteinia, Koellensteinia, Macroclinium, Rodriguezia, Solenidiopsis, andStenia. All new species are illustrated. A key is provided for 2-flowered species ofMacroclinium, PeruvianSigmatostalix, and PeruvianStenia. Solenidium (Solenidiopsis) peruvianum Schltr. is lectotypified.  相似文献   

19.
Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.  相似文献   

20.
The phylogeny ofFumariaceae, as inferred fromrps16 intron sequences, is compared with morphological data, and nrDNA-ITS. The different data sets are largely congruent and indicate that (1)Dicentra and the tribeCorydaleae as hitherto circumscribed are polyphyletic, (2)Lamprocapnos (=Dicentra spectabilis) is sister group to the rest of subfam.Fumarioideae, (3)Ehrendorferia, gen. nov. (=Dicentra chrysantha andD. ochroleuca) is basal in the latter group, (4) the morphologically aberrantIchtyoselmis, gen. nov. (=Dicentra macrantha) groups withDicentra s. str., (5) the genusCysticapnos should be included in the tribeFumarieae, (6)Dactylicapnos (=Dicentra subg.Dactylicapnos) is sister group toCorydalis, (7) the genusCorydalis is monophyletic, and consists of three subgenera:Chremnocapnos, stat. nov.,Sophorocapnos, stat. nov., andCorydalis. The following new combinations are validated:Ehrendorferia chrysantha, E. ochroleuca, Ichtyoselmis macrantha, andLamprocapnos spectabilis. Dedicated to emer. Univ.-Prof. DrFriedrich Ehrendorfer on the occasion of his 70th birthday  相似文献   

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