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1.
A. Jaylet 《Chromosoma》1966,18(1):79-87
Résumé Chez le Salamandridé Euproctus asper, le caryotype analysé à partir de testicules adultes et d'épiderme larvaire montre que le nombre chromosomique diploïde est de 24. Ces chromosomes se rangent en trois groupes principaux à l'intérieur desquels la plupart des éléments peuvent s'identifier individuellement grâce à leur indice centromérique.Le classement des chromosomes en trois groupes reste possible pour les figures haploïdes de 2e division méïotique spermatocytaire. Dans ce dernier cas on peut encore, à l'intérieur de deux des groupes, identifier individuellement chacun des éléments.Il ne semble pas y avoir d'hétérochromosomes morphologiquement différenciés dans cette espèce.
The karyotype of Euproctus asper (Urodela, Salamandridae) was analyzed from squash preparations of adult testes and larval epidermis. The diploid chromosome number is 24. These chromosomes can be classified into three groups. Most of the elements included in these groups can be identified individually by means of their length and arm-ratio. The classification into three groups remains possible for second meiotic division chromosomes. In the latter case, it is still possible to identify individually each chromosome in two of the three groups. There is no evidence of heteromorphic pairs in the present species.
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2.
《Comptes Rendus Palevol》2016,15(7):791-812
The land mammal record of the Vallès-Penedès Basin (Catalonia, NE Spain) ranges from the early Miocene (Ramblian) to the late Miocene (Turolian), that is from about 20 to 7 Ma. Here we present an updated review of the mammal succession focusing on biochronology as well as on environmental and faunal changes. Based on faunal similarities with central Europe, we interpret this basin as a transitional zone between the forested environments of northern regions and the more arid landscapes of the inner Iberian Peninsula. The quality of the Vallès-Penedès record and its chronostratigraphic control is clearly better for the late Aragonian and the Vallesian (between 12.6–9.0 Ma), especially for small mammals. Therefore, we analyze small mammal diversity dynamics during this interval. Contrary to previous analyses, which found an abrupt extinction event coinciding with the early/late Vallesian boundary (the Vallesian Crisis), our results show that this pattern is due to uneven sampling. Instead, taxonomic richness slowly decreased since the late Vallesian as a result of a series of extinctions that mostly affected forest-dwelling taxa.  相似文献   

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P. Rodriguez  N. Giani 《Hydrobiologia》1986,139(3):269-276
Three new species of aquatic oligochaetes (Annelida, Oligochaeta) collected in Spain are described. Two are Enchytraeids (Henlea andreae n.sp. and Enchytraeus thomasi n.sp.) and one is a Lumbriculid (Trichodrilus diversisetosus n.sp.).  相似文献   

5.
Pourriot  R.  Benest  D.  Rougier  C.  Clement  P. 《Hydrobiologia》1984,112(1):41-44
A comparative analysis of eight characters in two clones ofA. brightwelli and a clone ofA. intermedia, fed withParamecium orBrachionus, is made to determine the intraclonal, interclonal and interspecific variations in this complex of species.The trophi morphology appears the most species specific criterium whereas the other features (size of males, diameter and ornamentation of resting eggs, nuclear number in syncytial glands) show variability, either genetic or related to environmental conditions. The variation observed in the ornamentation of resting eggs and in the nuclear number of vitellogen was distributed along a continuous gradient.
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《Comptes Rendus Palevol》2014,13(7):569-585
Here, we revise all the published and unpublished scimitar-toothed cat remains from the Vallès-Penedès Basin (NE Iberian Peninsula), in order to confirm their taxonomic attribution to Machairodus aphanistus as well as to provide more precise information about its chronological distribution in this basin. The studied material (including dentognathic as well as postcranial remains) comes from the following localities: Can Mata indeterminate (late MN7+8 or MN9), Creu Conill 22 (MN9), Can Poncic 1 (MN9), Can Llobateres 1 (MN9), Santiga (MN9), La Tarumba 1 (MN10), Viladecavalls (MN10), Ronda Oest Sabadell ROS-D3 (MN10), and Torrent de Febulines (MN10). Most of the studied material fits well with the morphologic and metrical features characteristic of the Vallesian species M. aphanistus, with the exception of the remains from Creu Conill 22 (an undescribed partial P4 formerly attributed to this taxon), which belongs in fact to a medium-sized hyaenid. From a biostratigraphic viewpoint, the removal of the Creu Conill material from the hypodigm of M. aphanistus has important implications, because this locality (11.1 Ma) was considered to record the first appearance datum of this taxon in the Vallès-Penedès Basin. However, the report of a previously unpublished talus from Can Mata (late MN7+8 or MN9) indicates that this taxon was present in this basin at least by the earliest Vallesian. Therefore, our results indicate that the first appearance datum of Machairodus in the Vallès-Penedès Basin might be somewhat younger than previously assumed, although dating uncertainties for the Can Mata remains preclude a more precise assessment. In contrast, the new mandibular remains from ROS-D3 (MN10) are likely coeval with those from La Tarumba 1, with the last appearance datum of M. aphanistus in the Vallès-Penedès Basin corresponding to Torrent de Febulines (ca. 9.1 Ma). The postcranial material described from various Vallès-Penedès localities further indicates that M. aphanistus displayed less cursorial adaptations than its purported descendant Homotherium.  相似文献   

8.
《Comptes Rendus Palevol》2002,1(4):227-234
Two viperid snakes, Vipera natiensis sp. n. (belonging to the Vipera aspis group) and Vipera sp., have been found in the Pliocene of Minorca. On the other hand, an indeterminate viperid extends back the fossil record of the family in the Balearic Islands, to the Middle Miocene. These fossils represent the first report of viperids from the Balearic Islands. Vertebra of Vipera natiensis sp. n. are characterised by a concave anterior border of zygosphene, dorsoventrally flattened, short (as wide as long) and blunt prezygapophyseal processes. Centrum convex in transverse section, subcentral margins poorly marked and presence of two well defined subcotylar tubercles. Hypapophysis located posteriorly on the centrum and not prolonged anteriorly, or only slightly prolonged as a keel. The dorsal border of the neural spine is slightly thickened; the posterior border of the neural spine is markedly inclined posteriorly; as a result, the spine forms a posterior point, which is more or less developed, depending on the position of the vertebra along the vertebral column. The presence of Viperidae in the Neogene of the Balearic Islands involves the existence of a terrestrial connection between this archipelago and the continent during the Early Miocene and/or Middle Miocene and perhaps the presence of a later connection during the Late Miocene.  相似文献   

9.
Résumé L'auteur décrit en particulier à l'aide du microscope électronique les différentes couches constituant la paroi du proventricule de Syllidiens (Annélides Polychètes) en insistant spécialement sur celles (zones sous-épithéliales) situées de part et d'autre de la couche des muscles radiaires caractéristique de cet organe. II est montré que, contrairement à ce qu'il était admis jusqu'à présent, les zones sous-épithéliales sont constituées par des fibres de collagène noyées dans un matériel granuleux vraisemblablement de nature mucopolysaccharidique. D'autre part, un système d'attache particulier entre zones sous-épithéliales et musculature radiaire est mis en évidence.Les fibres de collagène de périodicité 560 Å constituent, autour de la musculature radiaire, un réseau à mailles rectangulaires hautement organisé. Dans l'assise la plus interne de ce réseau, les fibres sont allongées parallèlement à l'axe antéro-postérieur du Ver; dans l'assise la plus externe, elles sont disposées circulairement dans des plans transversaux.La signification de la présence de ces fibres de collagène (les seules existant dans tout le corps des Syllis étudiés) est évoquée. Les problèmes de leur origine et du rôle possible de cellules différenciées (musculaires) dans la synthèse de ce collagène sont analysés.
Presence of collagen in the proventriculus of Syllids
Summary The layers of the wall of the proventriculus of Syllids (Annelids Polychetes) were studied, mainly with the aid of the electron microscope. The areas on both sides of the radial musculature (subepithelial zones) were given special attention. Contrary to previous views, it was shown that the subepithelial zones contain collagen fibrils within a granular material probably of mucopolysaccharide nature. Furthermore, a system of special attachment devices between subepithelial zones and radial musculature was demonstrated.The collagen fibrils (periodicity 560 Å) form a highly organized network with rectangular meshes around the radial musculature. In the innermost layer of this network, the fibers run parallel to the antero-posterior axis of the worm; in the outermost layer, they run circularly.The significance of the presence of these collagen fibers, the only in existence in the entire organism studied, is discussed. The problem of their origin, and the possible role played by differentiated (muscular) cells in the synthesis of this collagen are analyzed.
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10.
Résumé L'étude par la méthode histochimique de fluorescence de Falck, du ganglion cérébroïde ét de la chaine nerveuse ventrale de Glycera convoluta K. a permis la mise en évidence de péricaryons et de fibres présentant une fluorescence jaune et verte. La nature et le métabolisme des amines mises en évidence histochimiquement ont été étudiées par des techniques biochimiques. La présence d'adrénaline et de 5-hydroxytryptamine a pu être établie avec certitude. Deux autres amines identifiées chromatographiquement comme étant de la dopamine et de la noradrénaline présentent cependant des caractéristiques spectrofluorimétriques légèrement différentes de ces deux substances.La rétention de la noradrénaline et de la dopamine étudiée par des techniques radiochimiques s'est montrée plus longue que dans le canal déférent du Rat. Les composants lipidiques, protéolipidiques et protéiques étudiés chromatographiquement sont apparus assez différents de ceux rencontrés chez les Mammifères.Des données récentes ont montré l'importance de l'arrangement spatial des groupements fonctionnels dans la molécule du médiateur par rapport à la (ou aux) protéine (s) lors de la fixation de la noradrénaline dans les fibres adrénergiques des Mammifères. Aussi peut on estimer que les différences observées entre les caractéres spectrofluorimétriques des catécholamines de G. convoluta et du Rat pourraient tenir plus à la forme de capture et de stockage des amines qu'à une différence profonde de leur nature chimique.
Biogenic amine study of Glycera convoluta K. (annelida, polychaeta)
Summary The supra-oesophageal ganglion and ventral nerve cord of Glycera convoluta K. were studied with the fluorescence method of Falck. Many perikarya and fibers show a green and yellow fluorescence. The nature and metabolism of the observed biogenic amines were studied by biochemical methods. Epinephrine and 5-hydroxytryptamine were certainly present. Two other amines show chromatographic characters of dopamine and norepinephrine, but exhibit a slight difference in their fluorimetric spectra with these two catecholamines.Radiochemical methods have shown that the retention of norepinephrine and dopamine is longer in the ventral nerve cord of G. convoluta than in the vas deferens of the rat.The lipids, proteolipids and proteins of G. convoluta were different from those found in mammals as demonstrated by chromatographic analysis.Recent findings have shown the importance of the spatial arrangement of active groups in the molecule of transmitter for its retention by the protein matrix in the adrenergic fibers of mammals. The differences found by spectrofluorimetry and by measurements of the time of retention between catecholamines of rat and G. convoluta can be explained by differences in the nature of the protein matrix or by the spatial arrangement of active groups in the transmitter molecule.
Nos remerciements vont à Mme L. Desgroux-Lelièvre et à M.B. Lesbats, pour la collaboration qu'ils nous ont apportée dans la réalisation de ce travail, ainsi qu'au personnel de la Station Biologique de Roscoff qui nous a aimablement fourni les animaux utilisés.  相似文献   

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Résumé La jeune spermatide possède un noyau arrondi, un diplosome proche de la membrane cellulaire auquel sont associées des formations paracentriolaires; une mitochondrie unique est disposée entre le diplosome et le noyau.Au cours de l'évolution de la spermatide, le noyau s'allonge latéralement, son grand axe étant perpendiculaire à l'axe flagellaire; la mitochondrie migre à l'extrémité latérale du noyau; le centriole distal donne un flagelle de type 9+0; le centriole proximal se prolonge le long du noyau puis sort de la cellule sous la forme d'un pseudo-flagelle. Le prolongement centriolaire est constitué de triplets classiques et de doublets d'un type particulier que nous avons appelés «doublets A–C».Les auteurs signalent la similitude des spermatozoïdes de cet Elopiforme avec les spermatozoïdes d'Anguilliformes ce qui serait en faveur de la proposition de Greenwood et al. de rassembler ces téléostéens dans le super-ordre des Elopomorphes.
The spermiogenesis of Albula vulpes (L. 1758) (albulidae fish)
Summary The early spermatid possesses a round nucleus and a diplosome which is close to the cellular membrane and with which paracentriolar formations are associated; a sole mitochondrion is located between the diplosome and the nucleus.During the spermatid evolution, the nucleus is laterally elongated, its main axis being perpendicular to the flagellar axis; the mitochondrion migrates towards the lateral end of the nucleus; the distal centriole is extended along the nucleus, then leaves the cell as a pseudoflagellum. This centriolar extension is made up of regular triplets and of a particular type of doublets that we have called A–C doublets.The authors call attention to the similarity between the spermatozoa of this Elopiforme and the spermatozoa of the Anguilliformes. This observation favours Greenwood et al.'s proposition, to place these teleost into the super-order of Elopomorpha.
Les auteurs tiennent à remercier Mr. C. Chauve et Mr. J.-N. Roy pour leur collaboration.  相似文献   

13.
Résumé L'étude de la sensibilité des 4 espèces de noctuelles,Mamestra brassicae L.,Spodoptera littoralis Boisduval,Spodoptera frugiperda Smith etScotia ipsilon Hübner, aux hyphomycètes a été conduite avec 10 souches dePaecilomyces fumoro-roseus (Wize) Brown & Smith, 6 deNomuraea rileyi (Farlow) Samson, 1 deBeauveria bassiana (Bals.) Vuill. et 1 deMetarhizium anisopliae (Metsch.) Sor. Les chenilles nouvelles-nées agées de moins de 16 h ont été exposées pendant 24 h sur des rondelles de feuilles contaminées par aspersion des inoculums, puis élevées individuellement à 25±1°C. A la dose de 3.105 conidiospores/cm2, l'activité pathogène des germes sur les chenilles varie dans de larges proportions suivant l'espèce-h?te et suivant l'isolat considérés. L'espèce la plus sensible à la plupart des souches estM. brassicae et la plus résistanteS. littoralis. Les germes les plus performants présentent des temps létaux 50% compris entre 2 et 3,5 j (à la dose de 3.105 spores/cm2) et des doses létales 50% de 103 à 104 conidiospores/cm2 (mortalités cumulées le 6e j après traitement); ce sont les isolats:P. fumoso-roseus no 13, 32, 39, 40 et 45 pourM. brassicae, N. rileyi no 5 pourS. littoralis; P. fumoso-roseus no 32 pourS. frugiperda etM. anisopliae no 139 pourS. ipsilon. La virulence élevée du pathotypeN. rileyi no 5 pourS. littoralis et son agressivité à l'égard des 3 autres noctuelles, confirment l'intérêt de cet hyphomycète en dehors de son aire d'origine (Sud-Est des Etats-Unis). Par ailleurs, les aptitudes des souches européennes deP. fumoso-roseus montrent que cette espèce présente des potentialités pour la lutte biologique contre divers noctuides.
Summary Bioassays were carried out on 1st instar larvae to determine the relative susceptibility of 4 noctuid species,Mamestra brassicae L.,Spodoptera littoralis Boisduval,Spodoptera exigua Smith andScotia ipsilon Hübner to 10Paecilomyces fumoso-roseus, 6Nomuraea rileyi, 1Metarhizium anisopliae and 1Beauveria bassiana isolates. Neonate larvae, 2 to 16 h old, were exposed for 24 h to leaf pieces treated with conidial suspensions of each fungal strain and then transferred to untreated foliage at 25±1°C. When tested at 3×105 conidia/cm2, pathogenic activity of hyphomycetes towards noctuids showed high variability depending on both host-species and fungal isolate.M. brassicae was more susceptible to tested isolates than the other 3 noctuids. In contrast,S. littoralis was the most resistant species. The most active pathotypes had LT 50 values ranging from 2 to 3,5 days at the concentration of 3×105 conidia/cm2 and LD 50 values ranging from 103 to 104 conidia/cm2 (mortality recorded at 6 days post exposure). According to these data, there were 5P. fumoso-roseus isolates (nos 13, 32, 39, 40 and 45) highly active againstM. brassicae, oneN. rileyi isolate (no 5) againstS. littoralis, oneP. fumoso-roseus isolate (no 32) againstS. frugiperda and oneM. anisopliae isolate (no 139) againstS. ipsilon. Bioassays establishing the high virulence of the FloridaN. rileyi isolate (no 5) to the Egyptian cottonworm and its pathogenic activity against the other tested noctuids, confirmed the interest for this fungal entomopathogen which has been demonstrated on noctuid populations in the southeastern United States. Moreover results of the host range assays of European isolates ofP. fumoso-roseus showed that this species appears to be an other potentially valuable microbial control agent against noctuid pests.
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14.
Barberapithecus huerzeleri gen. et sp. nov. (Primates, Pliopithecidae) is erected on the basis of material from Castell de Barberà (Middle to Late Miocene, ca. 11.2-10.5 Ma), in the Vallès-Penedès Basin (Catalonia, Spain), including: 15 teeth (representing most of the permanent dentition) from a single female individual (holotype); an isolated P/3 (paratype); and a male C1/ (referred to the hypodigm). Previously, this material had been only partially figured and described, being attributed to Pliopithecus or to a new taxon with possible crouzeliine affinities. The erection of a new genus is justified by several autapomorphic features, such as markedly buccolingually compressed and mesiodistally elongated C1/, extremely buccolingually compressed, and mesiodistally oriented C/1 main cusp, P/4 with a large trigonid subequal to the talonid, very large distal foveae on the M/1 and especially the M/2, and lower molars with a quadrangular central fovea and a mesially situated entoconid. These features are associated with a set of crouzeliine synapomorphies, such as buccolingually compressed and peripheralized cusps, well-developed crests, large and well-defined occlusal foveae, upper molars with long preprotocrista, short hypoparacrista, somewhat distally situated protocone and short distal fovea, distinct P/3 metaconid, well-developed P/4 premetacristid, and relatively narrow lower molars with a reduced entoconid. Although more primitive, Barberapithecus resembles Anapithecus in some derived features. Both taxa are included into a new tribe (Anapithecini), together with other crouzeliines except Plesiopliopithecus (tribe Crouzeliini). The retention of primitive, pliopithecine-like features in Barberapithecus suggests that anapithecins might have evolved from a Pliopithecus ancestor, so that as currently conceived the Crouzeliinae might be polyphyletic.  相似文献   

15.
《Comptes Rendus Palevol》2002,1(8):711-716
Fire-setting to open up mines has been used on hard rock since prehistoric times. In the copper-mining district of Cabrières, the existence of metre-sized spherical or sub-spherical cavities, sometimes spaced along the same vertical in an ore seam, has usually been ascribed to this method 〚12〛, 〚13〛, 〚20〛. Two AMS 14C dating of micro-charcoal found in dolomite and of burnt ore breccias related to extraction in these cavities give the ages 3830 ± 40 BP, cal BC 2340–2130 and 3900 ± 40 BP, cal BC 2480–2280, which is the first evidence in France of the use of fire-setting in prehistoric mines.  相似文献   

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New tragulid dental remains from the late Early Miocene (16.5–16.3 Ma, MN4) locality of Els Casots (Vallès-Penedès Basin, Catalonia, Spain) are described. This sample fits well, both in size and occlusal morphology, with the material of Dorcatherium crassum from the type locality (Sansan, France; MN6). We therefore attribute the tragulid from Els Casots to this species, also in agreement with its known chronostratigraphic range throughout Europe (MN4–MN6) and the previous records of this species from other MN4 localities of the Vallès-Penedès Basin. The described remains – which include the postcanine lower deciduous and permanent dentition, as well as several upper cheek teeth – constitute the most complete sample of D. crassum from the Iberian Peninsula. The presence of this species at Els Casots is consistent with the lacustrine depositional environment inferred from sedimentological evidence and associated fauna, and further confirms the nearby presence of densely forested environments with a humid climate with low seasonality.  相似文献   

18.
Résumé LesFormica polyctena qui ont reçu un radio-isotope (or radio-actif) l'ingèrent rapidement et peuvent le transmettre aux fourmilières voisines deFormica rufa. La radio-activité se localise dans l'abdomen des Fourmis. Il est probable qu'il s'agit d'un échange par voie buccale. Les fourmilières présentent souvent,avant tout marquage, une certaine radio-activité très faible, et due sans doute d'après des recherches en cours, à la présence naturelle de potassium dont l'isotope 40 est naturellement radio-actif.
Summary When a radioisotope is given toF. polyctena field nests the ants become active after a few hours; the activity is localized in abdomen only; it can be transmitted torufa nests in the neighbourhood. An oral exchange from polyctena to rufa is considered as a probable hypothesis. Ants nests show in many occasions,before radio-active tracer is given to, a small degree of activity, still unexplained.

Zusammenfassung Die Ameisen (Formica polyctena) die man mit einem Radioisotop (Radio-Gold) gefüttert hat zeigen nach kurzer Zeit eine messbare Radioaktivität welche an Nachbar-Völker derFormica rufa Art übertragen wird. Die Radioaktivität liegt am Abdomen der Ameisen. Es handelt sich wahrscheinlich um einen Futteraustausch. Die Ameisenvölker zeigen oft, auch vor der Fütterung mit Radioisotopen, eine schwache natürliche Radioaktivität dessen Ursache noch ungeklärt bleibt.
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