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1.
An annotated list of species of the Folsomia heterocellata group recorded in China is given. Folsomia cephalota n. sp., F. dorsomediaseta n. sp., F. longiseta n. sp., F. manubriopilosa n. sp., F. longdeica n. sp., and F. plenosensilla n. sp. are characterized by having a simple maxillary palp, four prelabral setae and no eyes. They differentiate mainly by characteristics of the furca. We report other species of the group which are recorded for the first time in China: Folsomia tianshanica Martynova, 1969, F. pseudovtorovi Potapov & Gulgenova, 2013, and F. pseudodecemoculata Stebaeva, 1971. This excludes F. wanxianensis Ji, Ding & Chen, 2007, for which we provide morphological remarks based on the type material. The group is mainly distributed in the central part of China (Chongqing, Gansu, southern part of Inner Mongolia, Ningxia and Shaanxi provinces). A key to all blind species with a simple maxillary palp is given.  相似文献   

2.
Background: Prescribed burning in peatlands is controversial due to concerns over damage to their ecological functioning, particularly regarding their key genus Sphagnum. However, empirical evidence is scarce.

Aims: The aim of the article is to quantify Sphagnum recovery following prescribed burns.

Methods: We completed nine fires at a raised bog in Scotland, achieving a range of fire severities by simulating drought in some plots. We measured Sphagnum cover and chlorophyll fluorescence Fv/Fm ratio (an estimate of photosynthetic capacity) up to 36 months post-fire.

Results: Cover of dominant Sphagnum capillifolium was similar in unburnt and burnt plots, likely due to its high moisture content which prevented combustion. Burning decreased S. capillifolium Fv/Fm 5 months after fire from 0.67 in unburnt plots to 0.44 in low fire severity plots and 0.24 in higher fire severity (drought) plots. After 22 months, Fv/Fm in burnt plots showed a healthy photosynthetic capacity of 0.76 and no differences between severity treatments. Other Sphagnum species showed similar post-fire recovery though their low overall abundance precluded formal statistical analysis.

Conclusions: S. capillifolium is resilient to low–moderate fire severities and the same may be true for a number of other species. This suggests that carefully applied managed burning can be compatible with the conservation of peatland ecosystem function.  相似文献   

3.
Trattinnickia is closely related toDacryodes and is transferred to the tribe Canarieae. Additional characters are proposed to supplement the weak characters that traditionally have been used to separateCrepidospermum andTetragastris fromProtium. The assumed “intermediate” genusParaprotium is shown to be an unnatural assemblage and is here merged withProtium. This revised concept of generic limits in the Neotropical Protieae and Canarieae leads to the following new combinations:Tetragastris occhionii (Rizzini) Daly,Protium pilosum (Cuatrec.) Daly,Protium nitidifolium (Cuatrec.) Daly,Protium vestitum (Cuatrec.) Daly, andDacryodes cuspidata (Cuatrec.) Daly. A key to the Neotropical genera of Burseraceae is provided.  相似文献   

4.
Abstract

1-O-Acetyl-2,3,5-tri-O-benzyl-4-thio-L-lyxofuranose 1 was transformed into O-benzyl- and O-acetyl-protected 1-(4-thio-L-lyxofuranosyl) nucleoside derivatives by use of the TMSOTf method. Debenzylation with boron tribromide or deacetylation with sodium methoxide yielded the corresponding pyrimidine (711, 17, 18, 26 and 27) and purine (29 and 34) nucleoside analogues. The anomeric configurations were determined by NMR spectroscopy and, in the case of the 5-halo- (79) and nitrouridine derivative 11 and the 6-methylcytidine derivative 27, by X-ray structural analyses. – The unprotected nucleosides were not antivirically inhibitory at 250 µM.  相似文献   

5.
《Journal of bryology》2013,35(4):417-422
Abstract

The Irish plant which, following Mitten, has commonly been referred to as Plagiochila ambagiosa Mitt. is specifically different from the type of P. ambagiosa, and is therefore described as Plagiochila atlantica F. Rose, sp. nov. It is now known from very restricted areas in Western Ireland, Western Scotland and North-western France.  相似文献   

6.
An extinct genus Abraracourcix n. gen. with A. curvivenatus n. sp. is described based on the specimen from the Lowermost Eocene Oise amber. The venation characters and possible hostplant relationships, as well as taxonomic position and biogeographical pattern of recent Pochazoides generic group are discussed.  相似文献   

7.
I. Introduction     
Background: Past research and ecological theory supports the hypothesis that alpine plants should be predominantly clonal, long-lived and reproduce by seed infrequently.

Aims: To challenge the entrenched view that alpine seedling establishment is uncommon and perhaps unsuccessful in maintaining alpine plant populations.

Methods: We looked for patterns in seedling establishment across a stress gradient of alpine sites and tested the notion that natural seedling recruitment would be reduced at higher altitudes due to a combination of stressful environmental conditions such as frosts, wind and extended snow cover.

Results: Seedlings were common at all study sites and there was a partial trend in mean seedling density with altitude. Seedling emergence was best predicted by a combination of altitude, plant litter and soil wilting point. Many seedlings survived to become established plants (37–61%) but there was no significant relationship between establishment and altitude. There was low similarity between the seedling flora and the standing vegetation, suggesting that patterns in seedling establishment are unlikely to be driving the patterns in the standing vegetation assemblage.

Conclusions: Although Australian alpine species predominantly reproduce vegetatively, this study shows that many plants depend on recruitment from seed in order to become established.  相似文献   

8.
《Journal of bryology》2013,35(4):363-373
Abstract

Three new species of Cololejeunea, C. dianae M. Wigginton, C. sanctae-helenae M. Wigginton and C. grossestyla M. Wigginton are described and illustrated from St Helena, South Atlantic Ocean. Details of their distributions are provided, and differences between the new taxa and other species of Cololejeunea are discussed. This is also the first report of the genus Cololejeunea from St Helena.  相似文献   

9.
《法国昆虫学会纪事》2012,48(6):465-470
Summary

After lectotype designations for both names, the synonymy between Cyrtolophus grandicornis Fairmaire, 1895 and Cyrtolophus viduus Ohaus, 1912, n. syn., is proposed. Pseudocyrtolophus n. gen. is described to accommodate Cyrtolophus limbicollis Ohaus, 1912, its type species, and a second species, Pseudocyrtolophus australis n. sp., which is described and compared to its most related species. The lectotype of Cyrtolophus limbicollis is designated. All species are illustrated. A map showing their distribution in Madagascar is given.  相似文献   

10.
《Journal of bryology》2013,35(4):635-647
Abstract

The results of a comparative study of Pohlia muyldermansii from Continental Europe and the British Isles are presented. Two varieties are recognized, var. muyldermansii from Belgium and the Netherlands and var. pseudomuyldermansii var. nov. from Great Britain, Ireland, Austria and Switzerland. P. camptotrachela is reported from Belgium and differences between this species and P. muyldermansii discussed.  相似文献   

11.
12.
Lixus petiolicola n. sp. is described from Northeastern Turkey. Ecological data and morphological characters are presented in comparison with closely related species Lixus furcatus Olivier from the Palaearctic subgenus Callistolixus Reitter. Host plant of the new species is Prangos sp. (Apiaceae). Female lays eggs in the petiole where immature stages then develop; one generation is produced per year. Lectotypes of Lixus sitta Sahlberg 1823; L. parallelus Boheman 1842; L. eversmanni Hochhuth 1847; L. ferulaginis Apfelbeck 1899, and L. furcatus longicollis Petri 1905 are designated. A new synonymy is established: L. furcatus Olivier 1807 [=L. eversmanni Hochhuth 1847, n. syn.]. The name of L. recurvus Olivier 1807 is resurrected, excluded from synonyms of L. furcatus and attributed to the L. iridis group.  相似文献   

13.
The names of all 135 species-group taxa of Cerambycidae described by N. N. Plavilstshikov are listed. Types of all these taxa preserved in the Zoological Museum of the Moscow State University and in the Zoological Institute (St. Petersburg) are catalogued, with lectotypes and paralectotypes designated. New synonymies are proposed: Pseudosieversia rufa (Kraatz, 1879) = Macrorhabdium ruficollis Plavilstshikov, 1915, syn. n.; Pseudo sieversia Pic, 1902 = Macrorhabdium Plavilstshikov, 1915, syn. n.; Agapanthia angelicae Reitter, 1898 = A. jacobsoni Plavilstshikov, 1915, syn. n. Dorcadion arietinum phenax Jakovlev, 1900, stat. n. is a valid name of the taxon known before as D. arietinum strandi Plav. Alosterna tabacicolor subsp. tokatensis Pic, 1901 (= A. t. caucasica Plavilstshikov, 1936, syn. n.) is regarded as a valid name (nomen protectum), and A. chrysomeloides var. subvittata Reitter, 1885 is regarded a nomen oblitum, as well as Cortodera umbripennis var. pallidipes Pic, 1898, while C. ruthena Plavilstshikov, 1936 is nomen protectum. Vadonia bipunctata puchneri Holzschuh, 2007, stat. n. is widely distributed in southern Ukraine and southern Russia from Dnepropetrovsk to Rostov-on-Don, and in the North Caucasus; specimens of this subspecies, as also specimens of V. saucia (Mulsant et Godart, 1855), stat. rest., known from the southern Crimea, constitute a part of the type series of V. bipunctata mulsantiana (Plavilstshikov, 1936).  相似文献   

14.
《Journal of bryology》2013,35(4):270-274
Abstract

A new species of Lepidopilidium (Pilotrichaceae, Hookeriales), L. crispifolium, sp. nov. from St Helena, South Atlantic Ocean is described and illustrated.  相似文献   

15.
《Journal of bryology》2013,35(4):581-587
Abstract

P. andrewsii appears to be widespread in the arctic regions of the U.S.S.R. and also in mountains of southern Siberia, the Altai Mountains. Except in the mountains of Central and Northern Europe the range of P. andrewsii does not overlap with P. annotina and P. camptotrachela.  相似文献   

16.
(+)-Marmelo Lactones A(VA) and B (VB) were synthesized from erythro-γ-methyl-l-glutamic acid (IA) and threo acid (IB), respectively. The absolute configurations of natural marmelo lactones were thus determined to be (2R, 4S) for (+)-marmelo lactone A and (2R, 4R) for ( – )-marmelo lactone B.  相似文献   

17.
Noel H. Holmgren 《Brittonia》1998,50(2):159-164
Two Nevada species are described here for the first time: Penstemon tiehmii N. H. Holmgren, which is endemic to Mount Lewis of the Shoshone Range in Lander County; and Penstemon rhizomatosus N. H. Holmgren, which is endemic to the central Schell Creek Range in White Pine County. They both belong to section Saccanthera and are closely related to P. kingii S. Watson, a Great Basin endemic of valley sagebrush habitats. Both new species are talus plants of higher elevations and differ from P. kingii principally in their rhizomatous habit, petiolate leaves, and pubescence of shorter hairs.  相似文献   

18.
Abstract

The synthesis of cyclic ADP-carbocyclic-ribose (2), as a stable mimic for cyclic ADP-ribose, was investigated. Construction of the 18-membered backbone structure was successfully achieved by condensation of the two phosphate groups of 19, possibly due to restriction of the conformation of the substrate in a syn-form using an 8-chloro substituent at the adenine moiety. SN2 reactions between an optically active carbocyclic unit 8, which was constructed by a previously developed method, and 8-bromo-N 6-trichloroacetyl-2′,3′-O-isopropylideneadenosine 9c gave N-1-carbocyclic derivative, which was deprotected to give 5′,5′-diol derivatives 18. When 18 was treated with POCl3 in PO(OEt)3, the bromo group at the 8-position was replaced to give N-1-carbocyclic-8-chloroadenosine 5′,5′-diphosphate derivative 19 in 43% yield. Treatment of 19 with 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride gave the desired intramolecular condensation product 20 in 10% yield. This is the first chemical construction of the 18-membered backbone structure containing an intramolecular pyrophosphate linkage of a cADPR-related compound with an adenine base.  相似文献   

19.
Six new species of Lepraria are described from North America: L. barbatica, L. cryophila, L. disjuncta, L. moroziana, L. terricola, and L. xanthonica. Lepraria torii is discussed and its range extended to include boreal eastern North America. Lepraria aurescens is reported as new to North America from Florida. Preliminary keys to the genus in North America are presented.  相似文献   

20.
Damage caused to rice production by coleopteran insects like rice weevil (Sitophilus oryzae), a stored grain insect pest and rice hispa (Dicladispa armigera), a pest of the growing plant is quite high. In order to combat the damage, generation of insect resistant transgenic rice plant was considered desirable. CryIIIA endotoxin ofBacillus thuringiensis var.tenebrionis, a 65 kDa protein toxic to coleopteran insects, figured as the candidate gene product. Thus, the cryIIIA gene was isolated from a local isolate ofBacillus thuringiensis var.tenebrionis. The gene was tailored at the N-terminal end to its minimal size by using a synthetic ATG codon which replaced the first codon next to ATG of threonine to proline. This modification did not affect the functional property of the gene product. A chimeric construct of the modifiedcryIIIA gene was developed containing CaMV35S promoter andnos terminator for plant expression. The expressibility of thecryIIIA gene inindica rice was judged through test for transient expression in indica rice protoplasts.  相似文献   

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