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1.
Flow cytometry was used to determine ploidy levels in the Czech and Slovak taxa of the genusPseudolysimachion (W.D.J. Koch)Opiz (=Veronica auct. p.p.,Scrophulariaceae). In total, 123 populations from the Czech Republic, Slovakia, Ukraine (one locality), Austria (one locality) and Hungary (one locality) were analyzed. InP. maritimum (L.)Á. Löve etD. Löve andP. spicatum (L.)Opiz, two cytotypes were found: diploid (2n=2x=34) and tetraploid (2n=4x=68). In both species the tetraploid cytotype predominated (P. maritimum: 41 tetraploid populations out of 45;P. spicatum: 57 tetraploid populations out of 58). The two cytotypes ofP. maritimum have no taxonomic significance because ploidy level is not obviously correlated with morphology, distribution pattern or ecology. Tetraploid populations ofP. spicatum belong to two morphologically different subspecies, subsp.spicatum and subsp.fischeri Trávní?ek. The diploid cytotype (one population only) should be provisionally classified as a third subspecies ofP. spicatum, which is morphologically similar to the Asian subsp.porphyrianum (Pavlov)Trávní?ek. Only diploid plants (2n=2x=34) ofP. orchideum (Crantz)Wraber were found; all 13 populations that were analyzed belong toP. orchideum s.str. One diploid population sample ofP. spurium subsp.foliosum (Waldst. etKit.)Holub (2n=2x=34) and one tetraploid sample ofP. incanum subsp.pallens (Host)Trávní?ek (2n=4x=68) were also analyzed. In addition, three tetraploid populations of hybrid origin were investigated:P. maritimum ×P. spicatum subsp.spicatum (one population) andP. maritimum ×P. spurium subsp.foliosum (two populations). While hybrid plants ofP. maritimum ×P. spicatum arose from tetraploid parental species, plants ofP. maritimum ×P. spurium probably resulted from a cross between tetraploidP. maritimum and diploidP. spurium. The putative origin and evolutionary importance of polyploids in thePseudolysimachion are discussed.  相似文献   

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3.
The type specimen ofGonioloboceras goniolobum (Meek), rediscovered by Spath in the British Museum, is the foundation for a more accurate comparative study of this and other species ofGonioloboceras.Gonioloboceras described asG. goniolobum byElias in 1938 is differentiated asGonioloboceras schmidti, new species. Suture sets (new term) for several growth stages inG. goniolobum (Meek),G. welleriSmith,G. schmidtiElias, G.eliasiMiller &Owen, andG. asiaticumLibrovitch are assembled and used for differentiation of the species.The Kazakhstan goniatite faunule containingG. asiaticum is considered of very late Pennsylvanian age.  相似文献   

4.
In the Lower Plattenkalk of Bergisch Gladbach occur, besides the well known?Hians”-beds, polymictic accumulations of shell material. Together with the valves ofMartinia inflata (Schnur),Uncinulus parallelepipedus (Br.) andIsopoma brachyptyctum (Schnur) are great numbers ofSpinatrypa tubaecostata (Paeck.) andAtrypa prisca gladbachensis n. subsp. In spite of the fact that the host rock was deposited as shell debris, in particular the rhynchonellids and atrypids are easily separated from it in a well preserved state. Atrypa (Desquamatia) prisca gladbachensis n. subsp. is commonly found with its alations intact. This subspecies, which is here described in some detail, fluorisched on a marly ooze bottom. The expanded valves increased the food gathering field, while the alations, surrounding the shell margin almost like a flange, functioned as effective particle filters. Because of this, the free valves floated under wave attack and became fossilized almost undamaged. The brachiopod shells and the organoplastic debris were washed on to discontinuity surfaces which probably had already been lithified by algal growth.  相似文献   

5.
The Bohemian speciesAnetoceras solitarius (Barrande 1865) is re-described, including the TurkishA. barrandei (De Verneuil 1866). The other Bohemian species areA. aff.advolvens Erben 1960 and?A. fritschi (Barrande 1877). A new speciesA. recticostatum n. sp. is described from the German Lower Devonian, and several still problematical species of the genus are discussed. Finally, the supposed phylogenetic position and the relations ofAnetoceras are pointed out. The Upper SiegenianA. hunsrueckianum Erben 1960 is regarded as most primitive coiled ammonoid and as connecting link between the bactritids, and early coiled ammonoids.Mimosphinctes Eichenberg is considered to be a descendant fromAnetoceras.  相似文献   

6.
Notice is given of the first skull-bones ofCeratodus rectangulus Linck found in the Germanic Trias; they have been compared with those ofC. sturii Tell. and the recent genusEpiceratodus. The number of fossil teeth ofCeratodus is much larger, relatively, than that of the bones of the skull. This is explained by the assumption that these dipnoans were not embedded in their natural biotops.  相似文献   

7.
Proschizophoria Maillieux is restudied and found to be related to the Silurian genusIdiorthis McLearn and a new genusCordatomyonia, type speciesCordatomyonia shupei, n. sp.Proschizophoria, Idiorthis, andCordatomyonia are united in the new subfamily Proschizophoriinae which is assigned to the dalmanellid family Rhipidomellidae. Rhipidomellidae and its included subfamilies Heterorthinae, Rhipidomellinae, and Proschizophoriinae are emended and newly diagnosed. A new dalmanellid genus,Megasalopina, is proposed for the Lower Devonian species“Dalmanella” elevata Williams & Breger and its allies. It is thought to have been derived from the draboviinid genusSalopina Boucot and therefore belongs to the Schizophoriidae.Dalmanellopsis Khalfin is removed from the synonymy ofLevenea and is shown to be related toSalopina.  相似文献   

8.
Five new species and two varieties from the sectionMultifidae are described from the Sino-Himalayan region. They are referred to the affinity ofP. multifida L. andP. griffithii Hook. f.; one of the new species is probably related toP. gerardiana Lindl. and one is intermediate between the species of the sectionsMultifidae andNiveae.  相似文献   

9.
The region of Iran, Iraq, Afghanistan and the neighbouring countries is important for some groups of the speciesLotus L., especially those of the circle ofL. corniculatus L. andL. gebelia Vent. The first group is represented by the speciesL. corniculatus L. with 4 subspecies (3 of which are important for this region), andL. tenuis Waldst. etKit. which here attains the eastern boundary of the continuous area of distribution, and by the eastern speciesL. krylovii Schischk. etSerg. andL. rechingeri Chrtková-?ertová. The second group is represented by the speciesL. gebelia Vent.,L. michauxianus Ser. in DC. andL. libanoticus Boiss. their areas of distribution covering mostly those regions. Most of the species show considerable variability within the species.  相似文献   

10.
The paper sums up the information which the author has so far collected about the habitats and phytocenotic conditions of the glacial relics ofScorpidium scorpioides (Hedw.) Limpr.,Calliergon trifarium (Web. etMohr.)Kindb.,Paludella squarrosa (Hedw.) Brid., andMeesia triquetra (Hook. etTayl.)Aongstr. in the Highlands ?eskomoravská vrchovina (Bohemian-Moravian Highlands) in Czechoslovakia. Simultaneously, it presents a survey of the localities in which the occurrence of these species has been ascertained up to now.  相似文献   

11.
The following genera are redefined:Albatrellus S. F. Gray,Heterobasidion Bref.,Haploporus Bond. et Sing. ex Sing.,Fomitopsis P. Karst. andRigidoporus Murrill two new subgenera are described:Polyporus subgen.Dendropolyporus Pouz. (type:Polyporus umbellatus) andRigidoporus subgen.Neooxyporus Pouz. (type:Polyporus latemarginatus); the genusOxyporus (Bourd. etGalz.)Donk is classified as a subgenus of the genusRigidoporus,Murrill and the generaBjerkandera P. Karst. andLeptoporus quél. are classified as subgenera of the genusTyromyces P. Karst. The new subfamilyAlbatrelloideae Pouz. (genera:Albatrellus andGrifola) is described and 14 new specific combinations are made. The new genusIrpicodon Pouz. (type:Irpex pendulus) is proposed.  相似文献   

12.
The paper sums up the information which the author has so far collected about the habitats and phytocenotic conditions of the glacial relics ofScorpidium scorpioides (Hedw.) Limpr.,Calliergon trifarium (Web. etMohr.) Kindb.,Paludella squarrosa (Hedw.) Bred., andMeesia triquetra (Hook. etTayl.) Aongstr. in the Highlands ?eskomoravská vrchovina (Bohemian-Moravian Highlands) in Czechoslovakia. Simultaneously, it presents a survey of the localities in which the occurrence of these species has been ascertained up to now.  相似文献   

13.
Some species ofAsterigerina are described and discerned, as they occur in different levels of the sequence from Eocene to Miocene in northwestern Germany.Asterigerina bartoniana (Dam) in the Eocene is followed byAsterigerina rotula haeringensis Lühr andAsterigerina brandhorstiana n. sp. in the Lower Oligocene (sensuBeyrich).Asterigerina gürichi gürichi (Franke), typical for the lowermost part of sequences of Upper Oligocene age, is furnished with a lectotype out ofFrankes material. This species is substituted by the subspeciesAsterigerina gürichi staeschei (Dam & Reinhold) in the Miocene. The localities of Lower Oligocene in littoral facies near Bünde (Westfalia) are mentioned and described. (Localities “Brandhorst” resp. “Hof Fahrenkamp” and newer outcrops).  相似文献   

14.
The new genusViriatellina Bou?ek, 1964 unites the two older species namedNovakia gemündina Runzheimer, 1932 andTentaculites fuchsi Kutscher, 1931. ThusViriatellina gemuendina (Runzheimer) is cancelled, on the other handViriatellina fuchsi (Kutscher) remains valid. RecentlyViriatellina fuchsi (Kutscher) has been found in the tentaculitiferous limestone of Thuringia.  相似文献   

15.
The chromosome number ofA. thaliana from three localities in Central Bohemia was found to be 2n=10. All the chromosomes (length 1,5–2,6μm) belong to the atelocentric type, four pairs (m) having the centromere in the median and one pair (sm) in the submedian region. In connection with the discussion on the origin ofH. suecica the author presents the following preliminary results: a) the failure to cross the tetraploidCardaminopsis arenosa (L.)Hayek withA. thaliana; b) the successful crossing of the diploidC. petraea (L.)Hiit. withA. thaliana; c) the discovery of a diploid population ofC. arenosa (2n=16) in the Tatra Mts. (Czechoslovakia).  相似文献   

16.
Relationship between roots and shoots ofPimpinella saxifraga L.,Petroselinum hortense Hoffm.,Lactuca sativa L., andBeta vulgaris subsp.esculenta (Salisbury) Gürke var.altissima Roessig was studied in irrigated and non-irrigated plants. It was found that the irrigation water did not influence distinctly the root-shoot ratio of the experimental plants. From the statical point of view, this relationship could be expressed by the following quantitative ratios for irrigated and non-irrigated plants: 3∶1 forPimpinella saxifraga L., 2∶1 forPetroselinum hortense Hoffm., 9∶1 forLactuca sativa L., and 1∶1 for beetroot. From the dynamic point of view it is possible to state that this ratio changes in the course of individual development. With plants cultivated for their aerial parts, it increased with age, while with plants cultivated for their roots, it decreased with age. The irrigation water produced much greater morphological changes (the shape and the surface area) in the root and shoot system of experimental plants.  相似文献   

17.
Im Artikel wird die ursprüngliche Gattungsdiagnose derGyalidea Lett. um die Merkmale der Pilzkomponente ergänzt. Die angenommenen verwandtschaftlichen Beziehungen derGyalidea zu der FamilieAsterothyriaceae werden diskutiert. Alle bisher festgestellten Arten mit Übersichten der revidierten Proben werden kurz beschrieben. Neue Taxa und Kombinationen:Gyalidea dodgei spec. n.,G. epiphylla spec. n.,G. mayaguezensis spec. n.,G. portoricensis spec. n.,G. fritzei (Stein) comb. n.,G. fritzei var.rivularis (Eitn.) comb. n.,G. hyalinescens (Nyl.) comb. n.,G. lecideopsis var.convarians (Nyl.) comb. n.,G. lecideopsis var.stigmatoides (Nyl.) comb. n.,G. mexicana (B. de Lesd.) comb. n. undG. subscutellaris (Vězda) comb. n.  相似文献   

18.
Up to nowMachimosaurus was known only from isolated teeth. Its systematic position was uncertain. Recently discovered remains ofMachimosaurus from the Upper Jurassic of Portugal allow a reconstruction of the skull. This find proves thatMachimosaurus belongs to the crocodilian family Teleosauridae. The genus comprises the only speciesMachimosaurus hugii H. v.Meyer. The speciesMachimosaurus mosae Sauvage & Liénard is based on heterogeneous material and is unmaintainable. Osteological characteristics show that the environment ofMachimosaurus was the open seas.  相似文献   

19.
Chromosome numbers of the Czechoslovak species of the genusLotus, from various localities have been determined. The paper includes the speciesLotus uliginosus Schkuhr,L.tenuis Waldst. etKit. andL. borbásii Ujhelyi.  相似文献   

20.
Previously we have characterized a threonine dehydratase mutant TDF383V (encoded by ilvA1) and an acetohydroxy acid synthase mutant AHASP176S, D426E, L575W (encoded by ilvBN1) in Corynebacterium glutamicum IWJ001, one of the best l-isoleucine producing strains. Here, we further characterized an aspartate kinase mutant AKA279T (encoded by lysC1) and a homoserine dehydrogenase mutant HDG378S (encoded by hom1) in IWJ001, and analyzed the consequences of all these mutant enzymes on amino acids production in the wild type background. In vitro enzyme tests confirmed that AKA279T is completely resistant to feed-back inhibition by l-threonine and l-lysine, and that HDG378S is partially resistant to l-threonine with the half maximal inhibitory concentration between 12 and 14 mM. In C. glutamicum ATCC13869, expressing lysC1 alone led to exclusive l-lysine accumulation, co-expressing hom1 and thrB1 with lysC1 shifted partial carbon flux from l-lysine (decreased by 50.1 %) to l-threonine (4.85 g/L) with minor l-isoleucine and no l-homoserine accumulation, further co-expressing ilvA1 completely depleted l-threonine and strongly shifted carbon flux from l-lysine (decreased by 83.0 %) to l-isoleucine (3.53 g/L). The results demonstrated the strongly feed-back resistant TDF383V might be the main driving force for l-isoleucine over-synthesis in this case, and the partially feed-back resistant HDG378S might prevent the accumulation of toxic intermediates. Information exploited from such mutation-bred production strain would be useful for metabolic engineering.  相似文献   

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