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1.
Most of the Tethyan species usually attributed to the genera Platypleuroceras, Uptonia and Dayiceras (Polymorphitidae) are in reality forms phylogenetically related to Metaderoceras, but which show convergence in their morphology. Their originality justifies the creation of a new genus, Dubariceras and two new species, D. dubari and D. freboldi.The palaeobiogeographic implications of this phylogenetic interpretation confirm the profound differences between Tethyan and Boreal faunas in the Carixian. The platycone Polymorphitidae (Platypleuroceras, Uptonia and Dayiceras) are almost completely restricted to the Boreal Realm, whereas the faunas of the Tethyan Realm largely comprise the Acanthopleuroceratidae (Tropidoceras), Metaderoceras and its allied genus Dubariceras.  相似文献   

2.
《Comptes Rendus Palevol》2019,18(7):849-875
Archeological sites usually provide important information about the past distribution of small vertebrate fauna, and by extension about past terrestrial environments and climate in which human activities took place. In this context, Belgium has an interesting location in northwestern Europe between the fully studied zooarcheological records of Germany and England. We present here the revision of the late Pleistocene (Marine Isotope Stages 3 and 2) collection of the “Caverne Marie-Jeanne” (Hastière-Lavaux, Namur), studied by Jean-Claude Rage in the 1970s and the revision of the whole “indeterminate” small vertebrate materials from the “Caverne Marie-Jeanne” stored in the Royal Belgian Institute of Natural Sciences (RBINS) Quaternary collections in search of more herpetofaunal remains. It is now by far the largest late Pleistocene collection at RBINS with more than 20,500 recognized bones of amphibians and reptiles and covering the last 60,000 years. The faunal list comprises two urodeles (Lissotriton gr. L. vulgaris and Salamandra salamandra), four anurans (Bufo gr. B. bufo-spinosus, Epidalea calamita, Rana temporaria and Rana cf. R. arvalis), three lizards (Lacerta cf. L. agilis, Zootoca vivipara and Anguis gr. A. fragilis), and three snakes (Natrix gr. N. natrix, Coronella austriaca, and Vipera berus). This study represents the first fossil record in Belgium for L. gr. L. vulgaris, R. arvalis, Z. vivipara, N. gr. N. natrix and C. austriaca. As a whole, this assemblage suggests a patchy humid landscape under colder and dryer climatic conditions in comparison with present ones. This study also underlines the necessity of a primary separation in larger taxonomical categories by the specialist itself.  相似文献   

3.
Treatment of 2,5-anhydro-1-bromo-1-deoxy-2,3-O-isopropylidene-1-p-nitrophenylhydrazono-d-ribose with methyl acetylenecarboxylate gave methyl 3-(2,3-O-isopropylidene-β-d-erythrofuranosyl)-1-p-nitrophenylpyrazole- (8) and 5-carboxylate (9). Amidification at C-5 of 8 was easier than at C-4 of 9. Similarly, dimethyl 3-(2,3-O-isopropylidene-β-d-erythrofuranosyl)- 1 - p-nitrophenylpyrazole-4,5-dicarboxylate gave specifically a 5-carbamoyl derivative, the structure of which was established by comparison of the 13C-n.m.r.spectrum with those of a series of glycosylpyrazoles. The correlation between the experimental values of the chemical shifts of the carbon atoms of the pyrazole ring and the values calculated by addition of the contributions of the various groups linked to the ring was better (R 0.98) than the correlations obtained by calculation by the CNDO/2 method of the total electron population (R 0.92) or of the π-electron population of each carbon atom (R 0.85).  相似文献   

4.
Treatment of α-L-fucose with sulfuryl chloride at low temperature gave mainly 2,3,4-tri-O-chlorosulfonyl-β-L-fucopyranosyl chloride (1) and a small proportion of the α-anomer (2). Both compounds adopt a 1C4 chair conformation. Methanolysis of 1 in the presence of silver carbonate and anhydrous calcium sulfate gave methyl 2,3,4-tri-O-chlorosulfonyl-α-L-fucopyranoside (the β-anomer being only present in small proportion), further converted into methyl α-L-fucopyranoside by treatment with a basic resin and a catalytic amount of sodium iodide. Methanolysis of 1 in the presence of sodium iodide gave directly methyl α-L-fucopyranoside, in a more rapid but less stereoselective way. Methanolysis of 2 in the presence of silver carbonate is very slow and gave, after removal of the chlorosulfonyl groups, methyl β-L-fucopyranoside with a rather poor stereoselectivity.  相似文献   

5.
This paper follows the first part: Legrand-Blain &alii, 1983,Geobios, no 16, fasc. 3.The brachiopods here described from the «Culm are: Schizophoria cf. resupinata, Rhipidomella michelini, Actinoconchus aff. paradoxus, Lamellosathyris gr. lamellosa, Cleiothyridina (Leiothycridina) nov. sp. gr. okensis, Podtsheremia (s.l.) convenarum nov. sp., Neospirifer gr. derjawini, Anthracospirifer (?) sp., Brachythyrina (Anthracothyrina) perextensa nov. subgen., nov. sp., «Spirifer lujkiensis, Zaissania nov. sp., Kitakamithyris or Torynifer (?) sp., Martinia minima. From shales associated with the Ardengost limestones, slightly different faunas are: Podtsheremia (s.l.) convenarum (?), Anthracospirifer (?) sp., Brachythyrina (Anthracothyrina) bressoni nov. subgen., nov. sp., Phricodothyris mosquensis, Martinia buckmani.The brachiopods from Ardengost limestones andassociated shales, well dated, are of upper Serpukhovian age. The «Culm ones might be heterochroneous, with Serpukhovian and (?) Bashkirian elements. The paleoecology of the brachiopods from limestones and associated shales indicates moderate and low energy environments. The «Culm brachiopods display both resedimentation and delicate preservation features. There is evidence of rather close palaeobiogeographic relationships with the northern Sahara: during the late Serpukhovian, a «Sahara-Pyrénées region could be distinguished, at the western part of the vast Tethysian province.  相似文献   

6.
6-O-β-D-Galactofuranosyl-D-galactose was obtained in crystalline form by condensation of 3,5,6-tri-O-acetyl-1,2-O-(1-methoxyethylidene)-α-D-galactofuranose with benzyl 2,3,4-tri-O-benzyl-α-D-galactopyranoside, followed by O-deacetylation and catalytic hydrogenation. This compound is identical with that isolated from the cell wall of Mycobacterium tuberculosis by partial acid hydrolysis.  相似文献   

7.
S Acker  J Duranton 《BBA》1975,387(2):279-287
Independence of special forms of chlorophyll a and chlorophyll holochromesZea mays L. seedlings were cultivated for 10 days with submission to 4 s illumination periods interspersed with dark periods varying in length from 30 min to 6 h depending on the lot analyzed. The results show that, for the case in which the dark periods were shorter than 1 h, the relative proportions of different spectroscopic chlorophyll forms (maxima at 662, 670, 677.5, and 684 nm) were constant. For longer durations of darkness between illuminations, the relative proportion of the form Ca670 increases, while that of Ca684 diminishes with the length of darkness; to a lesser extent, the relative proportion of Ca662 increases and a form Ca692 disappears. A scheme is proposed to explain the evolution of the relative proportions of the different spectral forms.The different chlorophyll holochromes present in the chloroplasts were also analysed. If the dark period was longer than 1 h, chlorophyll was associated with peptide chains of molecular weights 21 000 and 29 000. If the dark period was shorter than 1 h chlorophyll was associated with four peptide chains of molecular weights 21 000, 25 000, 29 000 and 70 000.The results taken together demonstrate that a given spectral chlorophyll a form cannot be associated with a definite chlorophyll holochrome.  相似文献   

8.
2-Acetamido-2- deoxy-6-O-, -xylopyranosyl-O-D-glucopyranose has been synthesized in crystalline form by condensation of 2,3,4-tri-O-acetyl-α-D-xylopyranosyl chloride (1) with benzyl 2-acetamido-3,4-di-O-acetyl-2-deoxy-β-D-glucopyranoside (2), followed by O-deacetylation and catalytic hydrogenation. Condensation of 2 with 2,3,4-tri-O-chlorosulfonyl-β-D-xylopyranosyl chloride, followed by dechlorosulfonylation and acetylation, gave benzyl 2-acetamido-3,4-di-O-acetyl-2-deoxy-6-O-(2,3,4-tri-O-acetyl-α-D-xylopyranosyl)β-D-glucopyranoside in crystalline form. O-Deacetylation, followed by catalytic hydrogenation, gave 2-acetamido-2-deoxy-6-O-α-D-xylopyranosyl-α-D-glucopyranose in crystalline form.  相似文献   

9.
José Luis Sanz 《Geobios》1982,15(6):943-949
A sauropod tooth, from the Barremian-Aptian ofGalve (Teruel), is described in Spain for the first time. This tooth probably belongs to the sauropod reported by A.F. de Lapparent (1), a Brachiosaurinae different of that reported by J.V. Santafé, M.L. Casanovas & J.L. Sanz (2) and J.L. Sanz, J.V. Santafé & M.L. Casanovas (3) from Morella (Castellón, Spain), Lower Aptian in age. It is probably a lower left piece with a developped worn surface. The subfamily Brachiosaurinae-sensuR. Steel, 1970 (4)-has a certain coherence of tooth morphology in respect of other Camarasauridae-sensuR. Steel, 1970 (4). The piece from Galve belongs to a Brachiosaurinae close to Brachiosaurus, though could differ of this genus in the structure and distribution of enamel ornamentation.  相似文献   

10.
Three sections of the Gachal Formation, Tang-e Vaveila, Rahdar, and Bakhshi, located in the Kalmard area near the Tabas town (Central Iran) are revised. Tang-e Vaveila is dated as latest Tournaisian (upper MFZ8) to early Viséan (upper MFZ9); Rahdar is latest Tournaisian (latest MFZ8); and Bakhshi exposes the whole early Viséan (lower and upper MFZ9) succession. The upper MFZ8 subzone is indicated by the presence of Eoparastaffellina ex gr. rotunda; the lower MFZ9 subzone by the appearance of Eoparastaffella ex gr. simplex, and the upper MFZ9 subzone by the more or less concomitant appearances of Eostaffella and Lapparentidiscus. Among the foraminiferal assemblages, the endothyroids and loeblichioids are diversified, whereas the eoparastaffellins, tournayelloids and lituotubelloids remain rare. Regionally, the tetrataxins are interesting, because five species of Tetrataxis succeed one another across the MFZ9 biozone. Rich populations of Eotextularia were also observed. Incertae sedis algae are relatively diversified with the classical moravamminales and aoujgaliales. An interesting true alga is mentioned, but left in open nomenclature, as Epimastoporeae indet. Among the other microfossils, Cryptophyllus, Hamulusella?, Draffania, and hexaphyllids are noteworthy. The new taxa are: Eoparastaffellinae n. subfam., Endolaxina paralaxa n. sp., and Vissarionovella? iranica n. sp.  相似文献   

11.
《Comptes Rendus Palevol》2016,15(5):501-514
Bats (Chiroptera, Mammalia) are a valuable and independent source of palaeoenvironmental information in Quaternary sites because bat assemblages are not necessarily produced by the same processes as those of other small mammals. Here, we report a small collection of bats (MNI 15) from a cave infill of the Aguilón P7 (AGP-7) site (Zaragoza, Spain) dated Late Pleistocene (MIS 3). This is one of the rare localities south of the Ebro River (right bank) with Neanderthal tracks; therefore, the palaeoenvironmental data provided here may help us to understand Neanderthal history. Nine bat taxa were identified, viz. Rhinolophus ferumequinum, Rhipposideros, Myotis gr. myotis/blythii, M. cf. bechsteinii, Memarginatus, Mdaubentonii, Plecotus gr. auritus/austriacus, Hipsugo savii vel. Pipistrellus kuhlii/nathusii, and Miniopterus schreibersii. The presence of a high number of yearlings of the former four species suggests the presence of breeding colonies. The surprisingly high diversity of the sample indicates a variegated vegetation cover and relatively high humidity for the MIS 3 stage in the region.  相似文献   

12.
Methyl 2-O-benzoyl-3-bromo-3,6-dideoxy-α-l-altropyranoside (4) and methyl 2-O-benzoy]-3-bromo-3,6-dideoxy-4-O-methyl-α-l-altropyranoside (5) have been prepared from methyl-α-l-rhamnopyranoside, respectively, in 2 and 3 steps. Reduction of 4 with lithium aluminium hydride followed by acid hydrolysis afforded the 3,6-dideoxy-l-arabino-bexose (l-ascarylose). The anhydro sugars 8 and 9 have been used as intermediates in the stereoselective synthesis of 6-deoxy-3-O-methyl-l-altropyranose (l-vallarose) and of 3-amino-3-degxy-l-altro sugars. Under azidolysis conditions, and according to the temperature, 5 gave unsaturated sugars such as 20 and the derived 26, or azido compounds such as 21 and 24, and the derived sugar methyl 2-amino-2,3,6-trideoxy-α-l-threo-hexopyranosid-4-ulose (25).  相似文献   

13.
《Comptes Rendus Palevol》2014,13(6):489-499
The Latest Cretaceous (Maastrichtian) terrestrial sedimentary sequences of the Haţeg Basin in Transylvania are well known for the so-called “Haţeg Island” vertebrate faunas, which evolved in endemic (insular?) conditions. In addition to frogs, lizards, turtles, crocodilians, birds and dinosaurs, peculiar multituberculate mammals have been recorded, all belonging to the family Kogaionidae. Here, a new species of the genus Barbatodon is reported from the Maastrichtian Şard Formation in the Transylvanian Basin (Alba County, Romania). Barbatodon oardaensis n. sp. is characterized by M1 cusp formula 3:4:2 and is much smaller than the two other Maastrichtian kogaionids from Transylvania, Barbatodon transylvanicus and Kogaionon ungureanui. The origin and paleobiogeography of kogaionids are discussed.  相似文献   

14.
Ammonites diartianus d'Orbigny is a Vascocerasoof late Cenomanian (Sciponoceras gracile Zone) age, occuring in both Sarthe (France) and southern England. It is the earliest vascoceratid known from France, and its recognition is of great significance, lending support to recent suggestions that the classic Vascoceras gamai - mundaeChoffat group are of Upper Cenomanian age.  相似文献   

15.
《Comptes Rendus Palevol》2014,13(3):223-234
The application of microtomography (mCT) to dental morphological studies has unveiled a new source of palaeobiological information, particularly in the analysis of the internal structures of teeth. In this study, we assess the expression of talonid crests at the enamel and dentine surfaces in lower permanent and second deciduous molars (M2 and dm2) of H. sapiens, H. neanderthalensis and Atapuerca-Sima de los Huesos (SH) hominins. In modern humans, talonid crests are described exclusively in the deciduous teeth (Korenhof, 1982) and interpreted as a primitive mammalian remnant of the talonid attachment to the trigonid. Here we report for the first time the expression of talonid crests of deciduous and permanent molars in H. sapiens, H. neanderthalensis and Middle Pleistocene hominins. We discuss possible evolutionary interpretations and suggest the importance of recording this feature in future studies.  相似文献   

16.
The conformation in solution of derivatives of methyl hexopyranosides has been studied by n.m.r. The esters of methyl 2,3-O-isopropylidene-α-D-manno- and -talopyranosides as well as their 4-deoxy-4-C-methyl analog having a manno configuration exist mainly in a flattened (4,0F) chair conformation (4C1). The presence in the talo epimer of the 4-deoxy-4-C-methyl analog of the bulky methyl group on the endo side of the bicyclic system results in a skew form (3S1). The methyl 4-deoxy-2,3-O-isopropylidene-4-C-methylene-α-D-lyxo-hexopyranosides monosubstituted at C-4′ adopt, in solution, a conformation close to 3S1, whichever their configuration (cis or trans) at the double bond, as indicated by their allylic coupling constants.  相似文献   

17.
Well-preserved Cretaceous (Albian–Turonian) radiolarians were extracted from radiolarian-bearing chert olistoliths of the Monagroulli Member within the Moni Mélange (Campanian-Maastrichtian, Southern Cyprus). Four assemblages were distinguished: Middle Albian–Lower Cenomanian (Thanarla spoletoensis Zone), Upper Albian–Lower Cenomanian (Thanarla spoletoensis Zone, Dorypyle? anisa Subzone), lowermost Turonian (base of Alievium superbum Zone) and Lower Turonian (Alievium superbum Zone). The radiolarian assemblages are diverse and have taxonomic composition similar to coeval assemblages of Italy and Spain. The sediments of the Monagroulli Member differ from coeval rocks of the Mamonia Complex (western Cyprus) by the more common presence of radiolarian cherts and may have been formed in the distal part of a continental margin with less input of clastic material. A new spicular radiolarian genus Cyprothamnus with 2 new species (C. multifurcatus and C. moniensis) is described from the Lower Turonian strata.  相似文献   

18.
《Comptes Rendus Palevol》2019,18(4):449-454
The saber-toothed cat Smilodon is a characteristic genus of the Pleistocene faunas of the American continent. Smilodon belongs to an extinct clade of felids that had hypertrophied blade-like upper canines. Because the length of the canines is so extreme, the killing bite of Smilodon is a hotly debated topic in vertebrate paleontology. Some authors have proposed that saber-toothed cats had a weak bite and their canines were fragile, not useful for attacking prey or penetrating bones. The aim of the present contribution is to describe two new specimens of Smilodon populator that have injuries on their skulls. Although it cannot be ruled out that the injuries were caused by a potential prey kicking the skull, the size, shape and general features of the injuries suggest that they were inflicted by the upper canines of another Smilodon individual during agonistic interactions.  相似文献   

19.
The autoradiographic analysis of the localization of [3H]adenosine-labeled cells exposed to concanavalin A (Con A) in vitro has confirmed that the altered migration of Con A-treated lymphocytes is a consequence of their slower rate of migration and delay in normal areas of traffic (5, 6). The mechanisms through which Con A alters cell migration were further investigated by studying the effects of several derivatives of Con A on the distribution of 51Cr-labeled lymph node cells. The results obtained show that the monomeric and dimeric forms of Con A were unable to modify cell traffic, a condition that was partially reversed when succinyl Con A-treated cells were exposed to divalent antibodies to Con A. This suggests that Con A may alter lymphocyte recirculation by actively modifying the membrane fluidity or the surface lateral transport of the lymphocyte. Whatever the exact mechanisms responsible for the altered migration are, they probably involve complex active processes that can be related to the heterogeneity of Con A receptors, the existence of subsets of cells with different reactivities to the lectin, or simply the result of a passive phenomenon dependent on the presence of Con A on the cell surface.  相似文献   

20.
《Comptes Rendus Palevol》2014,13(4):297-306
The genus Hypnomys Bate, 1918 includes some endemic Neogene chronospecies from Mallorca and Menorca, evolved in insularity conditions from the Lower Pliocene to the human arrival at the archipelago. The study of the allometric proportions (functional length and sagittal diameter) of the limbs’ long bones of Hypnomys eliomyoides Agusti, 1980 (Lower Pleistocene of Menorca), Hypnomys sp. (Pleistocene of Menorca), Hypnomys onicensis (Reumer, 1994) (Upper Pliocene-Lower Pleistocene of Mallorca) and Hypnomys morpheus Bate, 1918 (Upper Pleistocene of Mallorca) only indicates small differences with the garden dormouse (Eliomys quercinus Linnaeus, 1776) and other mainland rodents and insectivores. The study about the locomotion type by means of Similarity Matrix of Bou indicates that 1) Hypnomys spp. presents the greater similarities with the arboreal, jumping and gliding species; 2) the jumping and digging life style of Hypnomys spp. are more developed (25%) than in E. quercinus; 3) the walking locomotion of Hypnomys spp. is only a 7% greater than in E. quercinus; and 4) the degree of similarity with the gliding locomotion of Hypnomys sp. is greater (17%) than in E. quercinus. Some of this data indicates that Hypnomys spp. was better adapted to the arboreal life than E. quercinus, due to the relationship between the jumping and gliding capacities with the arboreal locomotion. The greater similarity of Hypnomys spp. with the walking locomotion does not necessarily involve more terrestrial habits. Our interpretation contrasts with earlier conclusions of Hypnomys life style (Hypnomys cf. onicensis and Hypnomys morpheus) where the terrestrial locomotion was overestimated in front of the arboreal locomotion. The locomotion type of Hypnomys would be related with the presence of important forest masses on the Balearic Islands during the Neogene, a different degree of environmental stress from that of the mainland ecosystems and a probable expansion of the ecological niche occupied by these species.  相似文献   

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