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1.
Fourteen herbarium specimens of Polytrichadelphus aristatus (Polytrichaceae, Musci) from the northern Andes were found to be colonized by ascomycetes. Thirty fungal specimens are indicated representing nine species and six genera. They belong to the first records of bryophilous fungi of northern South America. Five taxa are proposed as new: the genus Aphanotria, and the species A. paradoxa, Bryochiton macrosporus, Bryorella imitans, and Massarina polytrichadelphi. Most frequently found were Rogellia triseptata with six and Bryochiton macrosporus with five records. Four species develop their ascomata between the photosynthetic leaf lamellae, three are immersed within the abaxial side of the leaf nerve and two grow below the adaxial cuticle. The hypocrealean A. paradoxa, which has huge but almost invisible ascomata, merits special attention. Apart from a pronounced rostrum, these are completely immersed within the leaf nerve but longitudinally orientated occupying a type of microniche hitherto unknown. Hyphae of several species attack the thick-walled stereids of the leaf nerve and strongly contribute to leaf decomposition. Polytrichadelphus aristatus has an assemblage of parasitic ascomycetes quite different from that of P. magellanicus from southern South America.  相似文献   

2.
中国狸藻属校订   总被引:1,自引:0,他引:1  
李振宇 《植物研究》1988,8(2):25-42
本文对中国狸藻属分类群进行全面修订, 记载17种和1亚种, 其中8种为中国分布新记录, 1亚种为新等级。  相似文献   

3.
The distribution and coexistence of the fiddler crabs U. vocans borealis and U. lactea lactea was investigated in the upper shore of a sandy beach with respect to particle size, water content and total organic carbon content of the sediments. A clear segregation of habitats between the two species was apparent. U. lactea lactea were only found in sediments with significantly lower total organic carbon content. U. lactea lactea had a higher ratio for the size of third maxilliped to body size than U. vocans borealis. There was no statistical difference in the median sediment particle size of the habitats where both species were found on the study shore. U. lactea lactea was larger on shores where U. vocans borealis were absent. Smaller U. vocans borealis individuals occupied sediments with higher water content and finer particles. Smaller individuals of U. vocans borealis also possessed fewer spoon-tipped setae on second maxilliped than their larger conspecifics, which were found mostly on coarser sediments. U. lactea lactea spent significantly more time on the surface than in the burrow during low tide when compared with U. vocans borealis. Both Uca species exhibited similar desiccation resistance. U. lactea lactea tends to keep its frontal region in close contact with sediments to maintain moisture when being exposed to air.  相似文献   

4.
Allelopathic effects of the green macroalgae Ulva lactuca on the growth of three species of red tide microalgae, Heterosigma akashiwo, Alexandrium tamarense, and Skeletonema costatum were tested in laboratory co-cultures precluding the nutrient and light limitation and the effect of high pH. The growth of all three species of microalgae was significantly (p < 0.01) inhibited by fresh U. lactuca. In nutrient replete semicontinuous co-cultures with U. lactuca, H. akashiwo was completely dead in 12 days, and the growth of A. tamarense and S. costatum was reduced by 48 and 46%, respectively by U. lactuca within 12 days. The U. lactuca culture filtrate exhibited a significant (p < 0.05) inhibitory effect on the microalgae in the first 1 or 2 days, but growth resumed in the following days, and S. costatum growth was slightly (p > 0.05) promoted from day 3. The results suggested that the allelopathic compounds are quickly degradable and a long-term inhibition might need the continuous addition of compounds originated from macroalgae. Dried U. lactuca also exhibited inhibitory effects on the microalgae, and the normalized mean growth rates of microalgae decreased with the biomass of dried U. lactuca. The dependent relationships were y = −2.1208x2 + 1.0159x + 0.9752 for H. akashiwo, y = 0.7133x2 − 3.5813x + 1.1665 for A. tamarense, and y = −0.2114x2 − 1.063x + 1.0873 for S. costatum, respectively. The potential feasibility of utilization of dried U. lactuca against red tide microalgae was 2.0 g dry wt L−1. The present study shows that U. lactuca exhibits negative allelopathic effects on harmful bloom-forming microalgae.  相似文献   

5.
Recent finds of remarkable fossil plants from the Upper Triassic Yangcaogou Formation in Liaoning Province, PR China include branched, cupule-bearing structures referable to the corystosperm ovulate organ Umkomasia. This material is described and assigned to the proposed new species Umkomasia asiatica. The collection includes numerous isolated cupules and fragments of ultimate cupule-bearing axes. Two specimens consisting of portions of the main axis with attached, cupulate lateral axes have also been found. The main axis was at least 6.5 cm long, with each lateral axis bearing one to at least three pairs of stalked, ovoid cupules. The new Umkomasia is similar to U. franconica from the Jurassic of Germany, which is the only other known laurasian species, but the cupules are smaller and more elongated. It is also similar to many gondwanan forms, including the type species U. macleanii. Leaves associated with the Chinese Umkomasia species are tentatively referred to Thinnfeldia, and may have been produced by the same plant. Associated ovoid seeds with elongated, curved micropyles are similar to those of gondwanan species of Umkomasia. The fossils described here are, therefore, significant in representing the first report of corystosperm reproductive structures from Asia, and only the second report of Umkomasia from the entire northern hemisphere. The new Chinese fossils also support leaf-based evidence that the Corystospermales were present in Laurasia as early as the Late Triassic.  相似文献   

6.
Two species of the genus Antechiniscus have been found in Nothofagus forests in Australia. The new species A. moscali sp. n. is described. The New Zealand species A. parvisentus (Horning & Schuster, 1983) is redescribed from type material and from the new material from Australia. The taxonomic status of the two species within the genus is discussed.  相似文献   

7.
Within carnivorous plants, the bladderworts (Utricularia) possess the most complicated traps whose mechanisms are not yet completely understood. For the first time, a representative survey of different traps from both subgenera (Utricularia and Polypompholyx) is presented.

Based on scanning- and transmission electron microscopy, traps of 14 species of Utricularia (out of 215 species) representing 11 sections (out of 35 sections) and including all life forms (aquatic, epiphytic, and terrestrial) were investigated. Additionally, it was tested whether life forms correlate with trapping mechanisms. Most morphological and anatomical features of the traps vary considerably between the different life forms, e.g. position of trap and trap entrance as well as form and position of trap appendages. Morphological data support the basal position of subgenus Polypompholyx within the genus. Some characteristics of the traps of terrestrial Utricularia multifida (subgenus Polypompholyx) differ remarkably from traps of the other species, e.g. trap-door anatomy and trap walls. This might be an indication for a primordial (non-suction) trapping mechanism in the former species, similar to that of the eel-traps of the closely related genus Genlisea.  相似文献   


8.
After reconsidering the specific characters of Omphalia giovanellae and applying data from the sequences of the D1–D2 domain of the 28S rRNA gene and the ITS region of material collected in Italy and Spain, the species is ascribed to the genus Clitopilus. Considering the rather peculiar characters, especially the smooth spores, C. giovanellae is ascribed to the new section Omphaloidei sect. nov. The species is illustrated with drawings of fresh basidiomata observed in situ, as well as with SEM micrographs of the spores. Also based on DNA sequence data, O. farinolens, recently described from Spain, is shown to be a synonym of C. giovanellae.  相似文献   

9.
On the basis of new material from various Pacific regions we critically evaluate the characters for the taxonomy of the genus Questa and the former Questidae, a taxon now concluded to be a lineage within the family Orbiniidae. Two new species, Questa retrospermatica sp. n. from Hawaii (with similar forms also from New Caledonia and China), and Questa fijiensis sp. n. from Fiji, are described, and the morphological character patterns and phylogeny of the genus are revisited on the basis of a cladistic analysis. The finding of Hawaiian material of a new species, Levinsenia hawaiiensis sp. n., similar to Periquesta canariensis Brito & Nunez, 2002 (=Levinsenia canariensis comb. n.), challenges the view that Periquesta Brito & Nunez, 2002 is closely related to Questa; rather, it belongs to Paraonidae as a junior synonym of Levinsenia Mesnil, 1897.  相似文献   

10.
The corticioid basidiomycete Peniophorella praetermissa has long been regarded as a morphologically variable species complex. An ITS-based phylogenetic study based on a worldwide sampling was carried out using parsimony and Bayesian inference. The resulting trees feature three major clades, further divided into well-supported subclades. These could be considered as distinct species, a contention that is further supported by crossing test data. Only two out of the eight phylogenetic lineages identified can be distinctly morphologically characterized: P. odontiaeformis and P. subpraetermissa. P. odontiaeformis is an odontioid species with a paleotropical distribution whereas the taxa in the remaining subclades have smooth basidiomata and are distributed in temperate areas. P. subpraetermissa is known only from the type collection and is distinguished microscopically by its reddish brown apically encrustated cystidia. Taxa in the remaining subclades are impossible to distinguish from each other morphologically, and therefore, are viewed as a species complex, P. praetermissa s. lat. One of the subclades, which is widely distributed but restricted to the Northern hemisphere, is proposed to represent P. praetermissa s. str. An epitype is selected from the same area as the holotype, among the specimens studied here. However, the geographically most widespread clade with many representatives from both hemispheres is here referred to as P. pertenuis, a taxon that was previously considered a synonym to P. praetermissa.  相似文献   

11.
The genus Noculacia Mayer, 1903 is reviewed. Two new species, N. africana n. sp. and N. australiensis n. sp., are described based on material collected from southeast Africa and western-southern Australia, respectively. Noculacia bullata Mayer, 1903, the type species of the genus, is redescribed. Noculacia bogisa Mayer, 1903 is transferred to the genus Pseudoprotella Mayer, 1890 mainly on the basis of the presence of a well developed molar, the structure of pereopods 3 and 4, and the setal formula of the mandibular palp being 2-x-1. The genus Noculacia is presently composed of three species: N. africana n. sp., N. australiensis n. sp, and N. bullata Mayer, 1903. The genus Pseudoprotella is composed of P. bogisa (Mayer, 1903), P. inermis Chevreux, 1927, and P. phasma (Montagu, 1804).  相似文献   

12.
A total of 43 HPLC peaks tentatively considered to be sesquiterpene lactones was detected from a survey of the 18 taxa (eleven species and seven subspecies) of Helianthus sect. Helianthus using a recently developed microtechnique. All but one of the taxa showed characteristic sesquiterpene lactone patterns with between six and 15 compounds each. H. paradoxus appears to be the only species in the genus in which these compounds are not detectable. Comparison with available reference compounds allowed assignment of structures to 21 of the compounds. Known compounds can be classified into five major structural subtypes, the systematic distribution of which divides the section into three well-defined subgroups. The sesquiterpene lactone profiles of the other two annual species of the genus, H. agrestis and H. porteri, exhibit significant differences relative to any species of sect. Helianthus, which supports their exclusion from the section.  相似文献   

13.
The first representative of the genus Rhopalophthalmus in European waters, Rhopalophthalmus tartessicus sp. nov., is described from specimens sampled in the Guadalquivir estuary (southwestern Spain). At first identified as the Algerian species Rhopalophthalmus mediterraneus Nouvel, 1960, the new mysid species can be distinguished from its closest relative by its higher number of articles on the carpopropodus of the third to seventh thoracic endopods, by the well hook-shaped eighth thoracic endopod of the male, by the slender eighth thoracic endopod of the female, and by the smaller antennal scale and telson. Its geographical distribution appears restricted to estuarine habitats in southwestern Spain. Its swimming behaviour, with the ventral side facing upwards, is unusual in mysids. An updated identification key for the 19 known species in the genus, including information on the respective geographical distribution and habitat, is presented.  相似文献   

14.
Data for the flavonoids of 19 species in 10 sections of Ludwigia are presented. Eight flavonoids, comprising four glycoflavones, of which vitexin and isovitexin are reported for the first time in Ludwigia, and four flavonol glycosides, based on quercetin, are present in these species. Each section treated here has either glycoflavones or flavonols; presence of only onte class is considered to be advanced in the genus as a whole, compared with the presence of both glycoflavones and flavonols in the more generalized sects Myrtocarpus Cinerascentes, and Pterocaulon, which were examined earlier. Only glycoflavones are present in sects Macrocarpon (four species), Seminuda (five species), the ditypic African sect. Africana, the monotypic African sects Brenania, Cryptosperma, and Prieurea, the monotypic east Asian sect. Nipponia, and the monotypic pantropical section Fissendocarpa. Only flavonols are present in the monotypic Old Wodd section Caryophylloidea and sect. Oligospermum, which comprises nine species widespread in the OId and New Worlds.  相似文献   

15.
Phylogenetic studies using DNA sequences of two chloroplast regions, rbcL and trnL-F, demonstrate that the proposed genus Ceterach is a small clade within the large genus Asplenium, and sister to the Phyllitis clade. The Ceterach clade is characterised by irregular anastomosing veins and often densely scaled leaf blades. Its taxonomic status as a group nested within Asplenium is confirmed, and it is accepted here as a subgenus with seven species. The Ceterach clade comprises four lineages that correspond to disjunct polyploid complexes: the A. aureum clade forming a polyploid complex (4×, 6×, 8×) in Macaronesia, the A. ceterach clade forming a polyploid complex (2×, 4×, 6×) in the Mediterranean Basin, the A. paucivenosum clade (4×, 6×) in central Asia, and the A. dalhousiae clade (2×) with a disjunct distribution in the Himalaya, Yemen and Eritrea, and southwestern North America. Asplenium paucivenosum is sister to all other members of the Ceterach clade, whereas A. dalhousiae is sister to the A. aureum clade that includes tetraploid A. aureum, hexaploid A. lolegnamense, and octoploid A. parvifolium. Asplenium ceterach and its variations – including the hexaploid A. ceterach subsp. mediterraneum subsp. nov. first described below – form a monophyletic unit, sister to a clade consisting of A. aureum and A. dalhousiae. Asplenium cordatum from Africa and A. haugthonii from the isolated atlantic island of St. Helena are not members of the Ceterach clade, which suggests that leaf blades with dense indumenta have evolved at least twice within asplenioid ferns. The allotetraploid species A. hybridum has the chloroplast DNA from A. ceterach, and therefore the latter species is the maternal ancestor of the former. The other parent of this hybrid species is A. sagittatum that is nested within the sister clade of Ceterach, the Phyllitis clade comprising A. sagittatum and A. scolopendrium. The findings suggest that the current distribution of Ceterach is either the result of long-distance dispersal or represents fragmented relicts of a previously more widely distributed species.  相似文献   

16.
Angiostrongylus mackerrasae and A. cantonensis are closely related and their status as distinct species was tested by experimental hybridization. Hybridization between A. mackerrasae and A. cantonensis was observed and the morphology of the F1 hybrids was found to be intermediate between that of the parental species which suggests strongly that A. mackerrasae and A. cantonensis are both valid species. However, male F1 hybrids were sterile, whereas females were fertile; no evidence of parthenogenesis or other form of asexual reproduction were observed in either species. It is suggested that A. mackerrasae and A. cantonensis may cross breed in nature.  相似文献   

17.
Ehrendorferiana and its two included new species, E. austrocedri (the type species) and E. fitzroyae, are diagnosed. The new genus is a member of the predominantly temperate Neotropical subfamily Aphalaroidinae (Psyllidae). Based on the absence of metabasitarsal spurs it forms a likely monophyletic group with Baccharopelma, Panisopelma and Russelliana. The absence or paucity of long dorsal or marginal setae on the wing pads and caudal plate suggests a probable sister-taxon relationship with Russelliana. Apart from two species of Triozidae from New Zealand on Podocarpaceae, Ehrendorferiana is unique within Psylloidea in its host association with conifers, viz. Austrocedrus and Fitzroya (both Cupressaceae).

See also Electronic Supplement at: http://www.senckenberg.de/odes/05-12.htm  相似文献   


18.
Hitherto unknown metacercariae were found encysted in loaches (Misgurnus anguillicaudatus) from China. They were experimentally fed to golden hamsters, and gravid adults were recovered 1 week post-infection from their small intestines. A new species, Massaliatrema misgurni n. sp. (Heterophyidae), is described from the adults. This new species is different from M. gyrinicola Dollfus and Timon-David, 1960, in having a smaller acetabulum/oral sucker ratio, less branched vitellaria widely entering the intercecal anteroacetabular area and an almost median seminal receptacle; and from M. yamashitai Kamiya and Ohbayashi, 1975, in having a larger acetabulum/oral sucker ratio, with the seminal vesicle situated in the uterine loop and the vitellaria entering the intercecal anteroacetabular area. This report is the first record of M. anguillicaudatus as a second intermediate host of the genus Massaliatrema Dollfus and Timon-David, 1960.  相似文献   

19.
Based on characters of the fertile fronds, two species of fossil ferns from the Lower Cretaceous Potomac Group of the U.S.A., originally described as species of Osmunda by Fontaine in 1889, are transferred to the genus Anemia. The two species display primitive characters for that genus. Analysis of these and other characters of Anemia and related species, using parsimony and compatibility programs, suggests possible phylogenetic arrangements and facilitates delimination of three taxonomic units within Anemia that were already distinct during Cretaceous time. The subgenera Coptophyllum and Anemia are shown to be paraphyletic in the suggested phylogenies and the schemes agree with the known stratigraphy of the fossil ferns.  相似文献   

20.
Fruiting body guided sequence analysis of mycorrhizal root-tip mycelia is a powerful yet relatively sparsely explored method for species-level identification of mycorrhizal fungi. It is used in this study to indicate mycorrhizal associations in the corticioid (resupinate) genus Sistotrema of the cantharelloid clade through phylogenetic analysis of the ITS and nuLSU rDNA regions of two spatiotemporally co-occurring Sistotrema fruiting bodies and ectomycorrhizal root tips. The genus Sistotrema is confirmed to be polyphyletic, and the mycorrhizal species form a strongly supported monophyletic clade together with the stipitate genus Hydnum. The remaining lineages of Sistotrema may well be saprotrophic, the nutritional mode traditionally attributed to the genus, but the phylogenetic analyses show that they should be excluded from Sistotrema. The cantharelloid clade contains several mycorrhizal genera, but no symbiotic associations have previously been demonstrated for Sistotrema.  相似文献   

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