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1.
The contribution presents phytosociological analyses of the savanna vegetation of Yaguaramas belonging to the classCuratello-Byrsonimetea Borhidi 1979. According to the plant composition, the plant communities under study belong to the orderByrsonimo crassifoliae-Andropogonetalia teneris Bal.-Tul. ordo nov., where two alliances were distinguished, namely theGuillemineo brittonii-Aristidion refractae Bal.-Tul. all. nov. and theByrsonimo crassifoliae-Andropogonion teneris Bal.-Tul. all. nov. The associationsSclerio interruptae-Rhynchosporetum subimberbis Bal. Tul. ass. nov., andPolygalo omissae-Andropogonetum diodontis Bal.-Tul. ass. nov. (both endemic) were classified in the former alliance while the associationByrsonimo crassifoliae-Andropogonetum teneris Bal.-Tul. ass. nov. is a representative of the latter. The following subassociations were distinguished: theSclerio interruptae-Rhynchosporetum subimberbis utricularietosum fimbriatae Bal.-Tul. subass. nov., theByrsonimo crassifoliae-Andropogonetum teneris typicum Bal.-Tul. subass. nov., and theByrsonimo-Andropogonetum sclerietosum interruptae Bal.-Tul. subass. nov.  相似文献   

2.
A survey is given of three natural groups of the subsectionHeterophylla (Witas.)Fed. of the genusCampanula L. Within theSaxicolae four taxa of higher rank have been revealed:c. xylocarpa Kovanda (2n=34),C. gentilis Kovanda (2n=34),C. moravica (Spitzner)Kovanda subsp.moravica (2n=68), andC. moravica subsp.xylorrhiza (O. Schwarz)Kovanda (2n=102). BothAlpicolae andLanceolatae are represented by a single species: the first byC. cochleariifolia Lam. (2n=34), the latter byC. serrata (Kit. ap.Schult.)Hendrych (2n=34). Cytology, ecology and geographical distribution of all these taxa have been reviewed, and relationships to the other members of the complex discussed. Infraspecific variation within each species has also been examined.  相似文献   

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The Styginidae is regarded as an exclusively Ordovician family of trilobites, separate from the Scutelluidae. The hitherto poorly known genusProtostygina Prantl &P?ibyl, 1949 is revised. It is recorded with certainty only from the Llanvirn of the Czech Republic, and the type species is a senior synonym of“Raymondaspis” rubensi rubensi P?ibyl &VANěK, 1968 and“R.” rubensi lybar ?najdr, 1976. Two new styginid genera are proposed:Cyrtocybe, with type species“Raymondaspis” turgida Whittington, 1965, is known from the upper Arenig and lower Llanvirn of Newfoundland, Maine and Norway; andPromargo, with type speciesP.forteyi n. sp., occurs in the Arenig of Newfoundland and Spitsbergen.Turgicephalus Fortey, 1980 is regarded as a junior synonym ofRaymondaspis P?ibyl inPrantl &P?ibyl, 1949. Three genera are excluded from the Styginidae:Kirkdomina Tripp, 1962,Pseudostygina Zhou inZhou et al., 1982 andStyginella P?ibyl &Vaněk, 1971.  相似文献   

5.
Nyananyo B. L. (1988): The systematic significance of seed morphology and anatomy in thePortulacaceae (Centrospermae).—Folia Geobot. Phytotax., Praha, 23: 275–279.—The seeds of 115 species in eighteen genera of the familyPortulacaceae were examined with the scanning electron microscope. Longitudinal sections of seeds of representatives of all the genera were examined with the light microscope. Two broad groups based on shape of the seeds, ornamentation of the external surface of their testa, and the position of the embryo relative to the endosperm were recognised. The first group comprising three genera:Anacampseros L.,Grahamia Gillies andTalinopsis A. Gray, have seeds which are pyriform with wings and trichomes, and an embryo that is more or less parallel to the endosperm, while the second of fifteen genera:Calandrinia H.B.K.,Calyptridium Nuttall,Calyptrotheca Gilg,Ceraria Pearson etStephens,Claytonia L.,Lenzia Philippi,Lewisia Pursh,Lyallia Hooker fil.,Montia L.,Portulaca L.,Portulacaria Jacquin,Silvaea Philippi,Talinella Baillon,Talinum Adanson, andWangerinia Franz, are reniform without wings and with an embryo that is horse-shoe shaped around the endosperm.  相似文献   

6.
This communication describes a new savanna-like community, theBletio purpureae-Andropogonetum gracilis Balátová-Tulá?ková etR. Capote ass. nov., found in the woodless eastern part of the Sierra del Rosario Mountains (western part of Cuba). From the phytosociological point of view, it belongs to the allianceAchlaenion piptostachyae Balátová-Tulá?ková all. nov., the orderAchlaenetalia piptostachyae Balátová-Tulá?ková ord. nov., and the classSclerio baldwinii-Andropogonetea gracilis Balátová-Tulá?ková cl. nov. In the area under study four subassociations were distinguished: theBletio-Andropogonetum typicum Balátová-Tulá?ková et.R. Capote subass. nov., theB.-A. rhynchosporetosum fascicularis Balátová-Tulá?ková etR. Capote subass. nov., theB.-A. cassietosum aeschynomenes Balátová-Tulá?ková etR. Capote subass. nov., and theB.-A. stenandrietosum droseroidis Balátová-Tulá?ková etR. Capote subass. nov.  相似文献   

7.
Phytosociological analysis of savanna and forb-rich communities in the Pinar del Rio Province was done in the area of Remates de Guane; one locality lies on the seashore in the western part of the province. Altogether six associations were distinguished. Five of them, viz.Sclerio curtissii-Centelletum erectae, Schultezio guianensis-Rhynchosporetum fascicularis, Cassio diphyllae-Hypericetum stypheloidis, Polygalo squamifoliae-Dichromenetum seslerioidis andPhyllantho juncei-Aristidetum, all newly described in this paper, are classified into the order ofAcoelorapho-Colpothrinacetalia Bal.-Tul. inBal.-Tul. etCapote 1985 with two alliances. One association, thePaspalo debilis-Asteretum grisebachii Bal.-Tul. etCapote 1992, was put into the order ofAsteretalia grisebachii Bal.-Tul. inBal.-Tul. etCapote 1992 with one alliance bound to inland moving dunes. The plant composition reflects soil quality, above all the water regime. Very interesting is the presence of theByrsonimo crassifoliae-Andropogonetalia teneris-species in the association ofPolygalo-Dichromeneteum seslerioidis indicating the rich presence of stones in the upper part of the soil profile.  相似文献   

8.
The d,d-transpeptidase activity of Penicillin Binding Proteins (PBPs) is essential to maintain cell wall integrity. PBPs catalyze the final step of the peptidoglycan synthesis by forming 4 → 3 cross-links between two peptide stems. Recently, a novel β-lactam resistance mechanism involving l,d-transpeptidases has been identified in Enterococcus faecium and Mycobacterium tuberculosis. In this resistance pathway, the classical 4 → 3 cross-links are replaced by 3 → 3 cross-links, whose formation are catalyzed by the l,d-transpeptidases. To date, only one class of the entire β-lactam family, the carbapenems, is able to inhibit the l,d-transpeptidase activity. Nevertheless, the specificity of this inactivation is still not understood. Hence, the study of this new transpeptidase family is of considerable interest in order to understand the mechanism of the l,d-transpeptidases inhibition by carbapenems. In this context, we present herein the backbone and side-chain 1H, 15N and 13C NMR assignment of the l,d-transpeptidase from Bacillus subtilis (LdtBs) in the apo and in the acylated form with a carbapenem, the imipenem.  相似文献   

9.
On the basis of allozyme and cultivation data, and of additional herbarium material, a taxonomic and nomenclatural revision ofTaraxacum sect.Piesis A.J. Richards exKirschner et?těpánek is provided. The section is made up of halophilous, sexually reproducing taxa. InT. stenocephalum Boiss. etKotschy,T. pindicum Kirschner et?těpánek, sp. nov., andT. perenne Kirschner et?těpánek, sp. nov., a tetraploid chromosome number has been recorded, representing the only known case of sexuality at the tetraploid level in the genus. The complex ofT. stenocephalum, includes some geographically and morphologically extreme populations treated as subspecies: subsp.gumusanicum (Soest)Kirschner et?těpánek, comb. nov., subsp.magnum Kirschner et?těpánek, subsp. nov., and subsp.daralagesicum (Schischk.)Kirschner et?těpánek, comb. nov. In addition toT. bessarabicum (Hornem.)Hand.-Mazz., a widely distributed Eurasian species,T. stenocephalum, a complex centred in Transcaucasia and Anatolia, andT. pachypodum H. Lindb., a North African endemic, four new species are described:T. salsum Kirschner et?těpánek, sp. nov., a diploid endemic confined to E Crimea,T. perenne Kirschner et?těpánek, sp. nov., a tetraploid sexual species known only from SW Crimea,T. pindicum Kirschner et?těpánek, sp. nov., a remarkable tetraploid endemic to the Pindos Mts., Greece, andT. salsitatis Kirschner, ?těpänek etYirdirimli, sp. nov., an Anatolian diploid species. Furthermore, a hybrid betweenT. salsum andT. bessarabicum from Crimea (documented on the basis of allozyme data elsewhere) is given a binomial,T. xmesohalobium Kirschner et?těpánek, nothosp. nov.  相似文献   

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12.
Paulschulzia pseudovolvox (Schulz)Skuja, a member of theTetrasporales, is recorded for the first time for Czechoslovakia.Amphidinium radiatum Javorn., a member of theGymnodiniales is recognized. Further information about its variability is supplemented. The algae were studied in two reservoirs.  相似文献   

13.
Chromosome numbers are reported for two Mongolian species,Dracocephalum foetidum Bunge (2n=12) andKoenigia islandica L. (2n=14). The relationship ofD. foetidum toD. moldavica L. (2n=10) and some patterns of phenotypic variation inK. islandica are briefly discussed. The following new combinations are proposed:K. cyanadra (Diels) Měsí?ek etSoják,K. forrestii (Diels) Měsí?ek etSoják,K. hubertii (Lingelsh.) Měsí?ek etSoják, andK. nummularifolia (Meisn.) Měsí?ek etSoják.  相似文献   

14.
Here 13 species of the nonfoliicolous species of the lichen familyEctolechiaceae Zahlbr. em.Haf. are reported, which were found in a collection from Brazil. Six species are described as new:Badimia corticola (sp.n.),Calopadia isidiosa (sp.n.),C. psoromoides (sp.n.),C. subfusca (sp.n.),Tapellaria corticola (sp.n.), andT. schindleri (sp.n.). Seven species have been identified with earlier described species:Calopadia chacoënsis (Malme) comb. n. (=Lopadium chacoënse Malme),C. foliicola (Fée) Vězda,C. fusca (Müll. Arg.) Vězda,C. lecanorella (Nyl.) comb. n.,C. perpallida (Nyl.) Věda,C. phyllogena (Müll. Arg.) Vězda, andTapellaria epiphylla (Müll. Arg.) Sant. A key and illustrations for all studied species are provided, and the nomenclatural problem of the correct generic name of thePyrenotrichum Mont. (anamorph) forCalopadia Vězda orTapellaria Sant. (teleomorphs) are discussed.  相似文献   

15.
The present study deals with five genera of hepatics in Africa, Isotachis Mitt., Anastrophyllum (Spruce) Steph., Tritomaria Schiffn. ex Loeske, Gymnocoleopsis (Schust.) Schust. and Lophozia (Dum.) Dum. All African populations of the genus Isotachis Mitt. are considered to be one species, I. aubertii (Schwaegr.) Mitt. Four species of Anastrophyllum (Spruce) Steph. (s.l.), A. auritum (Lehm.) Steph., A. piligerum (Nees) Spruce, A. subcomplicatum (Lehm. et Lindenb.) Steph. and A. minutum (Schreb.) Schust., and two species of Tritomaria Schiffn. et Loeske, T. camerunensis S. Arnell and T. exsecta (Schrad.) Schiffn. ex Loeske occur in Africa. Gymmocoleopsis multiflora (Steph.) Schust. represents a genus and species hitherto unreported for the African flora. Finally, five Lophozia (Dum.) Dum. species, L. argentina (Steph.) Schust., L. capensis S. Arnell, L. decolorans (Limpr.) Steph., L. hedbergii S. Arnell and L. tristaniana (S. Arnell) Váňa, are reported from central and southern Africa; two of these (L. argentina (Steph.) Schust. and L. decolorans (Limpr.) Steph.) represent the first reports from Africa.  相似文献   

16.
The species of three genera—Sporoschisma Berk. etBr.,Sporoschismopsis Hol.-Jech. etHennebert andCatenularia Grove are treated in this paper from Czechoslovakia:Sporoschisma juvenile Boudier,S. mirabile Berk. etBr.,Sporoschismopsis moravica Hol.-Jech. etHennebert andCatenularia cuneiformis (Richon) Mason. The studied fungi produce the conidia in basipetal succession, endogenously or subendogenously, quite internally in large phialides or only inside open swollen collarettes.  相似文献   

17.
Scilla talosii Tzanoudakis etKypriotakis from the islet of Dia is described as a new species. It is an autumn-flowering taxon related toScilla autumnalis L. andS. obtusifolia Poiret but distinct morphologically and cytologically from both these taxa.S. talosii is polyploid with 2n=ca. 150 chromosomes.  相似文献   

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Up-to-date results of taxonomic and phytogeographic studies ofOenothera subsect.Oenothera in the eastern part of the Czech Republic (Moravia and Silesia) are presented. A new hybridogenous species,Oe. moravica Jehlík etRostański (=Oe. fallax × Oe. victorini), is described from S Moravia. Several taxa and hybrids are reported for the first time for the Czech Republic:Oe. victorini Gates etCatcheside (=Oe. rostanskii Jehlík),Oe. × wienii Renner exRostański,Oe. acutifolia × Oe. victorini. Other taxa are recorded from the eastern part of the Czech Republic for the first time:Oe. acutifolia Rostański,Oe. hoelscheri Renner exRostański,Oe. parviflora L.,Oe. subterminalis Gates. The taxonomy ofOe. pycnocarpa Atkinson etBartlett is discussed. A survey of species and hybrids ofOenothera subsect.Oenothera in the Czech Republic is added.  相似文献   

20.
Three genera of lignicolousHyphomycetes Septonema Corda,Hormiactella Saac. andLylea Morgan-Jones are discussed. Illustrations and determination keys are provided. Five species ofSeptonema—S. fasciculare (Corda) Hughes,S. leptaleum (Ellis & Harkn.) Hughes,S. pinicola Hol.-Jech.,S. secedens Corda andS. laricium Hol.-Jech.—and two species ofHormiactella—H. fusca (Preuss) Sacc. andH. asetosa Hol.-Jech.—have been found in Czechoslovakia. A new speciesS. pseudobinum Hol.-Jech. is described from Romania.Septonema tetracoilum (Corda Hughes is accommodated in the genusLylea Morgan-Jones.  相似文献   

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