991 resultados para syn-sedimentary


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Résumé Le « terrane » d'Anarak-Jandak occupe une position géologique clé au nord-ouest du Microcontinent Centre-East Iranien (CE1M), connecté avec le Bloc du Grand Kavir et la ceinture métamorphique de Sanandaj-Sirjan. Nous discutons ici l'origine de ces différentes unités, reliées jusqu'à présent à des épisodes orogéniques d'âge Précambrien à Paléozoïque inférieur, pour conclure finalement de leur affinité paléotéthysienne. Leur histoire commence par un épisode de rifting d'âge Ordovicien supérieur-Dévonien inférieur, pour se terminer au Trias par la collision des blocs Cimmériens dérivé du Gondwana avec le Bloc du Turan d'affinité asiatique (événement Eocimmérien). La plus importante unité métamorphique affleurant au sud-ouest de la région de Jandak-Anarak-Kaboudan est une épaisse séquence silicoclastique à grains fins contenant des blocs ophiolitiques (marginal-sea-type), et des associations basalte-gabbro à signatures géochimiques de type supra-subduction. Dans la région de Nakhlak, nous avons daté ces gabbros par la méthode U-Pb à 387f0.11 Ma ; les roches métamorphiques pélitiques ont donné des âges de refroidissement Ar-Ar pour la muscovite de 320 à 333 Ma. Ce complexe d'accrétion "varisque" a été métamorphisé dans le faciès schiste vert-amphibolite au cours de l'accrétion de la ceinture granitique d'Airekan, d'âge Cambrien inférieur (549±15 Ma par la méthode U/Pb), qui affleure aujourd'hui à l'extrémité nord-ouest du terrane d'Anarak-Jandak . La subduction vers le nord de l'océan Paléotéthys depuis le Paléazoïque supérieur jusqu'au Trias, a permis l'accumulation de grandes quantités de matériel océanique dans la zone de subduction. Par exemple, une succession de guyots (Anarak, Kaboudan, et Meraji Seamounts) et de hauts sous-marins, entrés en collision oblique avec le prisme d'accrétion, est à l'origine d'un léger métamorphisme de type HP qui affecte ces séries {âges Ar-Ar de 280 à 230 Ma). De plus, le magmatisme bimodal de Chah Gorbeh est caractérisé d'une part par des roches de type trondjémite-gabbros (262 Ma), d'autre part par des laves en coussin de type basaltes alcalins-rhyolites; ces roches magmatiques ont recoupé l'ophiolite d'Anarak lors de la mise en place de cette dernière dans la fosse interne de subduction. Quant au prisme d'accrétion de Doshakh, d'âge essentiellement Permien supérieur, i1 a été accrété le long de la marge continentale et métamorphisé dans le faciès schiste vert. La fermeture de la Paléotéthys s'enregistre finalement par la sédimentation dans le bassin d'avant pays du flysch de Bayazeh, d'âge probable Triasique. Le matériel issu de l'arc magmatique de la Paléotéthys est très bien préservé dans les dépôts infra-arc Dévonien supérieur-Carbonifère de Godar-e-Siah, ainsi que dans la succession d'avant-arc de Nakhlak. Pendant l'intervalle Paléozoïque supérieur-Trias, la région de Jandak a été soumise à un régime extensif de type bassin d'arrière-arc, dont un témoin pourrait être la ceinture ophiolitique d'Arusan, elle-même comparable aux écailles ophiolitiques d'Aghdarband au nord-est de l'Iran. Cet ensemble métamorphique est recoupé par des granites d'arc à collisionnel datés à 215±15 Ma. Dans la région de Yazd, témoin de la marge passive Cimmérienne, la sédimentation syn-rift Silurienne à Dévonienne inférieure a été interrompue pendant l'intervalle Trias moyen-Trias supérieur; il en a été de même pour les dépôts de plate-forme Paléozoïque supérieur. L'érosion, qui dans ce dernier cas a atteint le Permien, pourrait être liée au bombement flexural de la marge passive. La collision finale n'a pas induit de déformations trop importantes, et se caractérise par la mise en place de nappes sur la marge passive. Cet événement est scellé par des dépôts molassique du Lias. D'un point de vue régional, la zone s'étendant actuellement de la Mer Noire au Pamir a été soumise à six épisodes d'extension-compression du Jurassique inférieur (début du l'ouverture en position arrière-arc de la Néotéthys) à l'Eocène moyen. Par exemple, le terrane d'AnarakJandak, probablement situé entre le Kopeh Dagh et la plate-forme nord Afghane, s'est complètement détaché de sa patrie d'origine au début du Crétacé supérieur. Des preuves de cet événement se retrouvent dans les séries de plate-forme de Khur (préservation de séries syn-rift puis de marge passive). Les ophiolites de Nain et de Sabzevar sont de plus interprétée comme un témoin de l'existence de ce bassin d'arrière-arc. Dans l'intervalle Eocène-Oligocène, l'indentation par la plaque indienne de l'Eurasie a été contemporaine de la rotation horaire de fragments de l'ancien microcontinent Iranien et de la formation du CEIM. Cette rotation est responsable du transport du terrane d'Anarak-Jandak vers sa position actuelle en Iran Central, et de la dislocation de Terranes de moindre importance, comme le bloc de Posht-e Badam. Depuis le Miocène supérieur, et à la suite de la collision entre l'Arabie et l'Iran, le ternane d'Anarak-Jandak a subi des déformations liées à l'activité d'une zone de cisaillement dextre parallèle à la suture du Zagros, à l'arrière de l'arc magmatique d'Uromieh-Dokhtar. Résumé large public Le Microcontinent Centre-Est Iranien occupe une position géologique clé au centre de l'Iran. Les différentes unités qui le composent, reliées jusqu'à présent à des épisodes orogéniques d'âge Précambrien à Paléozoïque inférieur, sont maintenant rajeunies et liés à la fermeture de l'océean Paléotéthys. Leur histoire commence par un épisode de rifting d'âge Ordovicien supérieur à Dévonien inférieur, pour se terminer au Trias par la collision des- blocs Cimmériens, dérivés du Gondwana, avec le Bloc du Turan d'affinité asiatique. Dans la marge active asiatique de la Paléotéthys, nous avons daté les restes d'un océan marginal à 387±0.11 Ma. Ce complexe d'accrétion a été métamorphisé au cours de la réaccrétion de la ceinture granitique d'Airekan, d'âge Cambrien inférieur (549±15 Ma), qui affleure aujourd'hui à l'extrémité nord-ouest du « terrane » d'Anarak-Jandak correspondant à la plus grande partie de la région étudiée. Le matériel issu de l'arc magmatique de la Paléotéthys est très bien préservé et daté du Dévonien supérieur-Carbonifère. Pendant l'intervalle Paléozoïque supérieur-Trias, la région a été soumise à un régime extensif de type bassin d'arrière-arc, dont un témoin pourrait être la ceinture ophiolitique d'Arusan, comparable aux écailles ophiolitiques d'Aghdarband au nord-est de l'Iran. Cet ensemble métamorphique est recoupé par des granites datés à 215±15 Ma. La subduction vers le nord de l'océan Paléotéthys depuis le Paléozoïque supérieur jusqu'au Trias, a permis l'accumulation de grandes quantités de matériel océanique dans la zone de subduction. Par exemple, une succession de volcans sous-marins, entrés en collision avec le prisme d'accrétion, est à l'origine d'un léger métamorphisme de type HP qui affecte ces séries (280 à 230 Ma). Quant au prisme d'accrétion de Doshakh, d'âge essentiellement Permien supérieur, il a été mis en place le long de la marge continentale et métamorphisé dans le faciès schiste vert. La fermeture de la Paléotéthys s'enregistre finalement par la sédimentation dans le bassin d'avant pays du flysch de Bayazeh, d'âge Triasique. Dans la région de Yazd, on trouve les témoins de la marge passive Cimmérienne, la sédimentation syn-rift Silurienne à Dévonienne inférieure a été interrompue pendant l'intervalle Trias moyen-Trias supérieur, marqué par la flexuration de la marge passive lorsqu'elle rentra en collision avec la marge active asiatique. Cet événement est scellé par des dépôts molassique à charbon du Lias. Le «terrane» d'Anarak-Jandak, probablement situé à l'origine entre le Kopeh Dagh et la plate-forme nord Afghane, s'est complètement détaché de cette région au début du Crétacé supérieur lors de l'ouverture d'un bassin d'arrière-arc, engendré, cette fois, par la subduction de l'océan Néotéthys situé au sud des blocs cimmériens. Des preuves de cet événement se retrouvent dans les séries syn-rift, puis de marge passive de Khour. Les ophiolites de Nain et de Sabzevar sont interprétées comme un témoin de l'existence de ce bassin d'arrière-arc. Dans l'intervalle Eocène-Oligocène, l'indentation de l'Eurasie par la plaque indienne a été contemporaine de la rotation horaire de fragments de l'ancien microcontinent centre-Iranien. Cette rotation de près de 90° est responsable du transport du « terrane » d'Anarak-Jandak vers sa position actuelle. Abstract The Anarak-Jandaq terrane occupies a strategic geological situation at the north-western part of the Central-East Iranian Microcontinent (CEIM) and in connection with the Great Kavir Block and Sanandaj-Sirjan metamorphic belt. Our recent findings redefine the origin of these mentioned areas so far attributed to the Precambrian-Early Palaeozoic orogenic episodes, to be now directly related to the tectonic evolution of the Palaeo-Tethys Ocean, commenced by Late Ordovician-Early Devonian rifting events and terminated in the Triassic by the Eocimmerian tectonic event due to the collision of the Cimmerian blocks with the Asiatic Turan block. The most distributed metamorphic unit that is exposed from the south-west of Jandaq to the Anarak and Kaboudan areas is a thick and fine grain siliciclastic sequence accompanied by marginal-sea-basin ophiolitic blocks including basalt-gabbro association with supra-subduction-geochemical signature. These gabbros in the Nakhlak area were dated by U/Pb method at 387.6 ± 0.11 Ma and the metamorphic pelitic rocks yielded a range of 320 to 333 Ma muscovite-cooling ages based on 40Ar/39 Ar method. This "Variscan" accretionary complex was metamorphosed in greenschist-amphibolite facies during accretion to the Lower Cambrian Airekan granitic belt (549 ± 15 Ma by U/Pb method) that crops out at the northwestern edge of the Anarak-Jandaq terrane. Continued northward subduction of the Palaeo-Tethys Ocean during the entire Late Palaeozoic-Middle Triassic brought huge amount of oceanic material to the subduction zone. One chain of Carboniferous-Triassic oceanic rises and seamounts (the Anarak, Kaboudan, and Meraji Seamounts) obliquely collided with the accretionary wedge and created a mild HP metamorphic event (280-230 Ma based on 40Ar/39Ar results). Bimodal magmatism of the Chah Gorbeh area is characterized by a 262 Ma trondjemite-gabbro as well as pillow alkalibasalts-rhyolites which intruded the Anarak ophiolite when it was being emplaced within the inner-wall trench. The mainly Late Permian-Triassic Doshakh wedge was accreted along the continent and metamorphosed under lower greenschist facies and the probable Triassic Bayazeh flysch filled the foreland basin during the final closure. The Palaeo-Tethys magmatic arc products have been well preserved in the Late Devonian-Carboniferous Godar-e-Siah intra-arc deposits and the Triassic Nakhlak fore-arc succession. During the Late Palaeozoic-Triassic times, the Jandaq area has been affected by back-arc extension and probably the Arusan ophiolitic belt is the remnant of this narrow basin comparable to the Aqdarband ophiolitic remnant in north-east Iran. This metamorphic belt was intruded by 215 ± 15 Ma arc to collisional granites. In the passive margin of the Cimmerian block, on the Yazd region, the Silurian-Early Devonian syn-rift succession as well as the nearly continuous Upper Palaeozoic platform-type deposition was interrupted during the Middle to Late Triassic time, local erosion down to Devonian levels may be related to flexural bulge erosion. The collision event was not so strong to generate intensive deformation but was accompanied by some nappe thrusting onto the passive margin. It is finally unconformably covered by Liassic continental molassic deposits. Related to the onset of Neo-Tethyan back-arc opening in Early Jurassic to Mid-Eocene times, six periods of extensional-compressional events have differently influenced an elongated area, extending from the West Black Sea to Pamir. The Anarak-Jandaq terrane which was situated somewhere in this affected area, probably between the Kopeh Dagh and North Afghan platform, was completely detached from its source at the beginning of the Late Cretaceous

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The Ljubija siderite deposits, hosted by a Carboniferous sedimentary complex within the Inner Dinarides, occur as stratabound replacement-type ore bodies in limestone blocks and as siderite-sulfides veins in shale. Three principal types of ore textures have been recognized including massive dark siderite and ankerite, siderite with zebra texture, and siderite veins. The ore and host rocks have been investigated by a combination of inorganic (major, trace, and rare earth element concentrations), organic (characterization of hydrocarbons including biomarkers), and stable isotope geochemical methods (isotope ratios of carbonates, sulfides, sulfates, kerogen, and individual hydrocarbons). New results indicate a marine origin of the host carbonates and a hydrothermal-metasomatic origin of the Fe mineralization. The differences in ore textures (e.g., massive siderite, zebra siderite) are attributed to physicochemical variations (e.g., changes in acidity, temperature, and/or salinity) of the mineralizing fluids and to the succession and intensity of replacement of host limestone. Vein siderite was formed by precipitation from hydrothermal fluids in the late stage of mineralization. The equilibrium fractionation of stable isotopes reveals higher formation temperatures for zebra siderites (around 245A degrees C) then for siderite vein (around 185A degrees C). Sulfur isotope ratios suggest Permian seawater or Permian evaporites as the main sulfur source. Fluid inclusion composition confirms a contribution of the Permian seawater to the mineralizing fluids and accord with a Permian mineralization age. Organic geochemistry data reflect mixing of hydrocarbons at the ore site and support the hydrothermal-metasomatic origin of the Ljubija iron deposits.

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Our paper aims to give a thorough description of the infra-ophiolitic melanges associated with the Mersin ophiolite. We propose new regional correlations of the Mersin melanges with other melange-like units or similar series, located both in southern Turkey and adjacent regions. The palaeotectonic implications of the correlations are also discussed. The main results may be summarized as follows: the infra-ophiolitic melange is subdivided into two units, the Upper Cretaceous Sorgun ophiolitic melange and the Ladinian-Carnian Hacialani melange. The Mersin melanges, together with the Antalya and Mamonia domains, are represented by a series of exotic units now found south of the main Taurus range, and are characteristic of the South-Taurides Exotic Units. These melanges clearly show the mixed origin of the different blocks and broken formations. Some components have a Palaeotethyan origin and are characterized by Pennsylvanian and Lower to Middle Permian pelagic and slope deposits. These Palaeotethyan remnants, found exclusively in the Hacialani melange, were reworked as major olistostromes in the Neotethys basin during the Eo-Cimmerian orogenic event. Neotethyan elements are represented by Middle Triassic seamounts and by broken formations containing typical Neotethyan conodont faunas such as Metapolygnathus mersinensis Kozur & Moix and M. primitius s. s., both present in the latest Carnian interval, as well as the occurrence of the middle Norian Epigondolella praeslovakensis Kozur, Masset & Moix. Other elements are clearly derived from the former north Anatolian passive margin and are represented by Huglu-type series including the Upper Triassic syn-rift volcanic event. These sequences attributed to the Huglu-Pindos back-arc ocean were displaced southward during the Late Cretaceous obduction event. The Tauric elements are represented by Eo-Cimmerian flysch-like and molasse sequences intercalated in Neotethyan series. Additionally, some shallow-water blocks might be derived from the Bolkardag para-autochthonous and the Taurus-Beydaglari marginal sequences.

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Taxonomic study of Leschenaultia Robineau-Desvoidy (Diptera, Tachinidae). The genus Leschenaultia Robineau-Desvoidy, 1830 is redescribed. Two genera are considered as its junior synonyms: Echinomasicera Townsend, 1915 syn. nov. and Parachaetopsis Blanchard, 1959 syn. nov. Thirty two especies are treated, as follows: 18 described as new, Leschenaultia aldrichi, sp. nov. (Brazil, Santa Catarina), L. arnaudi sp. nov. (Haiti, La Salle), L. bergenstammi sp. nov. (Peru, San Martin), L. bessi sp. nov. (Brazil, Santa Catarina), L. bigoti sp. nov. (Peru, Huanuco), L. blanchardi sp. nov. (Equador, Cuenca), L. braueri sp. nov. (Brazil, Mato Grosso), L. brooksi sp. nov. (Brazil, Rio de Janeiro), L. coquilletti sp. nov. (Brazil, Santa Catarina); L. cortesi sp. nov. (Venezuela, Maracay), L. currani sp. nov. (Brazil, São Paulo), L. loewi sp. nov. (Mexico, Vera Cruz), L. macquarti sp. nov. (U. S. A., Arizona), L. reinhardi sp. nov. (Canada, Quebec), L. sabroskyi sp. nov. from (U. S. A., California), L. schineri sp. nov. (U. S. A., California), L. thompsoni sp. nov. (Mexico, Mexico City), L. townsendi sp. nov. (Mexico, Puebla), and 14 known species, for these, diagnoses are given: L. adusta (Loew, 1872); L. americana (Brauer & Bergenstamm, 1893); L. bicolor (Macquart, 1846) = L. fusca (Townsend, 1916) syn. nov.; = Parachaetopsis proseni Blanchard, 1959 syn. nov.; L. ciliata (Macquart, 1848); L. exul (Townsend, 1892); L. fulvipes (Bigot, 1887); L. grossa Brooks, 1947; L. halisidotae Brooks, 1947; L. hospita Reinhard, 1952; L. hystrix (Townsend, 1915) comb. nov., L. jurinioides (Townsend, 1895); L. leucophrys (Wiedemann, 1830) = Leschenaultia latifrons (Walker, 1852) syn. nov. = Parachaeta nigricalyptrata (Macquart, 1855) syn. nov.; L. montagna (Townsend, 1912); L. nuda Thompson, 1963. One species was not examined, Leschenaultia nigrisquamis (Townsend, 1892), and two were not recognized, L. trichopsis (Bigot, 1887) and L. hirta Robineau-Desvoidy, 1830. Keys for Nearctic and Neotropical species (only for males) are provided, as well as geographical distribution and illustrations for each species.

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Eryphus Perty, 1832 and Tacyba, a new genus of Heteropsini (Coleoptera, Cerambycidae). Some species, up to now, included in Callideriphus Blanchard, 1851 are rearranged in: a) those congeneric with Callideriphus grossipes Blanchard, 1851 and b) not congeneric. The first set of species will be treated in a future paper; the second one, on the other hand, is subdivided into Eryphus Perty, 1832 and Tacyba gen. nov. Eryphus Perty, 1832 (type species: Eryphus bipunctatus Perty, 1832), a valid genus, is redescribed and a key for the species is also provided. The following species are transferred to Eryphus: E. bivittatus (Melzer, 1934) comb. nov., E. carinatus (Zajciw, 1970) comb. nov., E. flavicollis (Fisher, 1938) comb. nov., E. laetus (Blanchard, 1851) comb. nov., E. marginatus (Zajciw, 1970) comb. nov., E. picticollis (Gounelle, 1911) comb. nov., E. transversalis (Fairmaire & Germain, 1864) comb. nov. New synonym proposed: Eryphus bipunctatus Perty, 1832 = Callideriphus atricollis Melzer, 1931. New taxa described: Eryphus tacuarembo sp. nov. (Uruguay, Tacuarembó), E. carioca sp. nov. (Brazil, Rio de Janeiro); Tacyba gen. nov. (type species: Callideriphus maculatus Cerda, 1988). Species transferred to Tacyba and synonyms: T. maculata (Cerda, 1988) comb. nov., T. tenuis (Blanchard, 1851) comb. nov. = Callideriphus testaceicornis Fairmaire & Germain, 1859 syn. nov. = Callideriphus clathratus Fairmaire & Germain, 1860 syn. nov. = Callideriphus niger Philippi & Philippi, 1864 syn. nov. Callideriphus flavicollis m. quadripunctatus Fuchs, 1961 and Callideriphus flavicollis m. reductus Fuchs, 1961, both names of infrasubspecific category (not available under the rules of ICZN), are herein treated as intraspecific variation of Eryphus picticollis (Gounelle, 1911) which occur in southern Brazil and Argentina.

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The genus Callideriphus Blanchard, 1851 (Coleoptera, Cerambycidae, Heteropsini). The genus Callideriphus comprises only two species: C. grossipes Blanchard, 1851 (type species) and C. tucumanus sp. nov. (Argentina, Tucumán). The type locality of C. grossipes had been originally indicated as Chile, but it is supposedly considered erroneous. Its distribution, actually, extends from Southeastern Brazil up to Argentina, along the Atlantic Forest. This species is extremely variable in regard to its coloration and elytral punctation. Two subspecies are recognized: C. grossipes grossipes Blanchard, 1851 (BRAZIL: Minas Gerais, Espírito Santo, São Paulo, Paraná, Santa Catarina) and C. grossipes flavipennis Melzer, 1934 (BRAZIL: Santa Catarina, Rio Grande do Sul; ARGENTINA: Chaco, Entre Ríos, Buenos Aires). Four intermediate forms are recorded and commented. Redescription and a key to species are added. Nomenclatural changes: Callideriphus grossipes grossipes Blanchard, 1851 = C. grossipes var. brasliensis Melzer, 1923 syn. nov. = C. rubricollis Melzer, 1934 syn. nov.; Callideriphus grossipes flavipennis Melzer, 1934 stat nov. = C. signaticollis Melzer, 1934 syn. nov.

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Revision of the genus Mecocephala Dallas, 1851 (Heteroptera, Pentatomidae). The genus Mecocephala Dallas, 1851 is revised, and some taxonomic and geographical distribution data are evaluated. The following species are considered to belong to this genus: M. acuminata Dallas, 1851 = M. holmbergi Pirán, 1969 syn. nov., M. curculionoides Pirán, 1959, M. bonariensis sp. nov., M. magna sp. nov., M. maldonadensis sp. nov., and M. zikani sp. nov.; their distribution is restricted to southern Neotropical Region. Other species, formerly placed in Mecocephala, are considered, respectively: M. rubripes Berg, 1894 incertae sedis, M. darwini Kirkaldy, 1909 incertae sedis, M. atra Bergroth, 1914 incertae sedis, Paramecocephala uruguayensis (Pirán, 1970) comb. nov., Paramecocephala fusca (Haglund, 1868) comb. nov. A key to the species is presented.

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Restructure of the genus Deois Fennah; description of a new genus and new species (Homoptera, Cercopidae, Tomaspidinae). The genus Deois Fennah is reviewed and some changes in the taxonomy are introduced. The genus and its four subgenera are redefined, having now the following composition: 1) subgenus Deois (Deois) with: D. (D.) correntina (Berg, 1879), D. (D.) grandis Sakakibara, 1979, D. (D.) knoblauchii (Berg, 1879) (formerly in D. (Pandysia)), D. (D.) morialis (China & Myers, 1934), D. (D.) mourei Cavichioli & Sakakibara, 1994, D. (D.) piraporae Sakakibara, 1979, D. (D.) pseudoflavopicta (Lallemand, 1938) comb. nov. (formerly in Mahanarva) = D. (D.) similis Sakakibara, 1979 syn. nov., D. (D.) rubropicta Sakakibara, 1979, D. (D.) spinulata sp. nov., D. (D.) terrea (Germar, 1821), D. (D.) uniformis (Distant, 1909). 2) subgenus Deois (Pandysia) with: D. (P.) bergi sp. nov., D. (P.) crenulata sp. nov., D. (P.) schach (Fabricius, 1787) = Sphenorhyna transiens Walker, 1851 syn. nov.. 3) Deois (Fennahia) with: D. (F.) coerulea (Lallemand, 1924), D. (F.) flexuosa (Walker, 1851). 4) Deois (Acanthodeois) with: D. (A.) flavopicta (Stål, 1854), Deois (A.) incompleta (Walker, 1851). The genus Orodamnis Fennah, 1953 stat. nov. (formerly Deois (Orodamnis)) with: Orodamnis rhynchosporae (China & Myers, 1934) comb. nov. The genus Deoisella gen. nov. is described for: Deoisella fasciata sp. nov. (type species) and Deoisella picklesi (China & Myers, 1934) comb. nov.

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The following nomenclatural changes are made: Amastris convoluta (Fabricius, 1781) comb. nov. (formerly Darnis; Hebetica); Amastris maculata Funkhouser, 1922 = Amastris fasciata Broomfield, 1976 syn. nov. = Amastris pseudomaculata Broomfield, 1976 syn. nov. = Amastris inermis Broomfield, 1976 syn. nov. = Amastris sakakibarai Broomfield, 1976 syn. nov.; Amastris elevata Funkhouser, 1922 = Amastris vismiae Haviland, 1925 syn. nov. = Amastris flavifolia Funkhouser, 1927 syn. nov.

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The genus Chalcolepidius is revised. Type specimens of 65 nominal species, except C. costatus Pjatakowa, 1941, C. fleutiauxi Pjatakowa, 1941 and C. viriditarsus Schwarz, 1906, are examined. Eighty five species are studied, of which 34 are synonymyzed and 12 new species described; three species, C. alicii Pjatakowa, 1941, C. haroldi Candèze, 1878 and C. unicus Fleutiaux, 1910, formely included in this genus, are not congeneric and are removed; C. validus Candèze, 1857 is revalidated. The genus is now formed by 63 species. Redescriptions, illustrations and a key for the examined species, and a cladistic analysis for groups of species are also included. New synonyms established: C. apacheanus Casey, 1891 = C. simulans Casey, 1907 syn. nov. = C. acuminatus Casey, 1907 syn. nov. = C. nobilis Casey, 1907 syn. nov.; C. approximatus Erichson, 1841 = C. aztecus Casey, 1907 syn. nov. = C. niger Pjatakowa, 1941 syn. nov.; C. attenuatus Erichson, 1841 = C. cuneatus Champion, 1894 syn. nov. = C. tenuis Champion, 1894 syn. nov.; C. aurulentus Candèze, 1874 = C. candezei Dohrn, 1881 syn. nov. = C. grossheimi Pjatakowa, 1941 syn. nov.; C. bomplandii Guérin, 1844 = C. humboldti Candèze, 1881 syn. nov.; C. chalcantheus Candèze, 1857 = C. violaceous Pjatakowa, 1941 syn. nov.; C. cyaneus Candèze, 1881 = C. scitus Candèze, 1889 syn. nov. = C. abbreviatovittatus Pjatakowa, 1941 syn. nov.; C. desmarestii Chevrolat, 1835 = C. brevicollis Casey, 1907 syn. nov.; C. gossipiatus Guérin, 1844 = C. erichsonii Guérin-Méneville, 1844 syn. nov. = C. lemoinii Candèze, 1857 syn. nov.; C. inops Candèze, 1886 = C. murinus Champion, 1894 syn. nov.; C. jansoni Candèze, 1874 = C. mucronatus Candèze, 1889 syn. nov.; C. lacordairii Candèze, 1857 = C. exquisitus Candèze, 1886 syn. nov. = C. monachus Candèze, 1893 syn. nov.; C. lenzi Candèze, 1886 = C. behrensi Candèze, 1886 syn. nov.; C. oxydatus Candèze, 1857 = C. jekeli Candèze, 1874 syn. nov.; C. porcatus (Linnaeus, 1767) = C. peruanus Candèze, 1886 syn. nov. = C. flavostriatus Pjatakowa, 1941 syn. nov. = C. herbstii multistriatus Golbach, 1977 syn. nov.; C. rugatus Candèze, 1857 = C. amictus Casey, 1907 syn. nov.; C. smaragdinus LeConte, 1854 = C. ostentus Casey, 1907 syn. nov. = C. rectus Casey, 1907 syn. nov.; C. sulcatus (Fabricius, 1777) = C. herbstii Erichson, 1841 syn. nov; C. virens (Fabricius, 1787) = C. perrisi Candèze, 1857 syn. nov.; C. virginalis Candèze, 1857 = C. championi Casey, 1907 syn. nov.; C. viridipilis (Say, 1825) = C. debilis Casey, 1907 syn. nov.; C. webbi LeConte, 1854 = C. sonoricus Casey, 1907 syn. nov.; C. zonatus Eschscholtz, 1829 = C. longicollis Candèze, 1857 syn. nov. New species described: C. albisetosus sp. nov. (Ecuador), C. albiventris sp. nov. (Mexico: Veracruz), C. copulatuvittatus sp. nov. (Venezuela), C. extenuatuvittatus sp. nov. (Venezuela), C. fasciatus sp. nov. (Mexico: Durango), C. ferratuvittatus sp. nov. (Ecuador), C. proximus sp. nov. (Mexico: Sinaloa), C. serricornis sp. nov. (Mexico: Veracruz), C. spinipennis sp. nov. (Mexico: Veracruz), C. supremus sp. nov. (Venezuela), C. truncuvittatus sp. nov. (Mexico: Tamaulipas) and C. virgatipennis sp. nov. (Mexico: Durango). Redescribed species: C. angustatus Candèze, 1857, C. apacheanus Casey, 1891, C. approximatus Erichson, 1841, C. attenuatus Erichson, 1841, C. aurulentus Candèze, 1874, C. bomplandii Guérin-Méneville, 1844, C. boucardi Candèze, 1874, C. chalcantheus Candèze, 1857, C. corpulentus Candèze, 1874, C. cyaneus Candèze, 1881, C. desmarestii Chevrolat, 1835, C. dugesi Candèze, 1886, C. erythroloma Candèze, 1857, C. eschscholtzi Chevrolat, 1833, C. exulatus Candèze, 1874, C. fabricii Erichson, 1841, C. forreri Candèze, 1886, C. fryi Candèze, 1874, C. gossipiatus Guérin-Méneville, 1844, C. inops Candèze, 1886, C. jansoni Candèze, 1874, C. lacordairii Candèze, 1857, C. lafargi Chevrolat, 1835, C. lenzi Candèze, 1886, C. limbatus (Fabricius, 1777), C. mexicanus Castelnau, 1836, C. mniszechi Candèze, 1881, C. mocquerysii Candèze, 1857, C. morio Candèze, 1857, C. obscurus Castelnau, 1836, C. oxydatus Candèze, 1857, C. porcatus (Linnaeus, 1767), C. pruinosus Erichson, 1841, C. rodriguezi Candèze, 1886, C. rostainei Candèze, 1889, C. rubripennis LeConte, 1861, C. rugatus Candèze, 1857, C. silbermanni Chevrolat, 1835, C. smaragdinus LeConte, 1854, C. sulcatus (Fabricius, 1777), C. tartarus Fall, 1898, C. validus Candèze, 1857, reval., C. villei Candèze, 1878, C. virens (Fabricius, 1787), C. virginalis Candèze, 1857, C. viridipilis (Say, 1825), C. webbi LeConte, 1854, C. zonatus Eschscholtz, 1829.

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Systematics, phylogeny and geographical distribution of the South American species of Centris (Paracentris) Cameron, 1903, and Centris (Penthemisia) Moure, 1950, including a phylogenetic analysis of the "Centris group" sensu Ayala, 1998 (Hymenoptera, Apoidea, Centridini). A cladistic analysis with the objective of testing the hypothesis of monophily of Centris (Paracentris) Cameron, 1903, and of studying its phylogenetic relationships with the other subgenera that belong to the Centris group, sensu Ayala, 1998, and the relationships among the species that occur in South America, is presented. Centris (Paracentris) is a group of New World bees of amphitropical distribution, especially diversified in the Andes and in the xeric areas of South and North America. Thirty-one species were included in the analysis, four considered as outgroup, and 49 characters, all from external morphology and genitalia of adult specimens. Parsimony analyses with equal weights for the characters and successive weighting were performed with the programs NONA and PAUP, and analyses of implied weighting with the program PeeWee. The strict consensus among the trees obtained in all the analyses indicates that C. (Paracentris), as previously recognized, is a paraphyletic group. In order to eliminate that condition, the subgenera C. (Acritocentris), C. (Exallocentris) and C. (Xerocentris), all described by SNELLING (1974) are synonymized under C. (Paracentris). The subgenus C. (Penthemisia) Moure, 1950, previously considered a synonym of C. (Paracentris), is reinstated, but in a more restricted sense than originally proposed and with the following species: Centris brethesi Schrottky, 1902; C. buchholzi Herbst, 1918; C. chilensis (Spinola, 1851), C. mixta mixta Friese, 1904, and C. mixta tamarugalis Toro & Chiappa, 1989. Centris mixta, previously recognized as the only South American species of the subgenus C. (Xerocentris), a group supposedly amphitropical, came out as the sister-species of C. buchholzi. The following South American species were recognized under Centris (Paracentris): Centris burgdorfi Friese, 1901; C. caelebs Friese, 1900; C. cordillerana Roig-Alsina, 2000; C. euphenax Cockerell, 1913; C. flavohirta Friese, 1900; C. garleppi (Schrottky, 1913); C. klugii Friese, 1900; C. lyngbyei Jensen-Haarup, 1908; C. mourei Roig-Alsina, 2000; C. neffi Moure, 2000; C. nigerrima (Spinola, 1851); C. toroi sp. nov.; C. tricolor Friese, 1900; C. unifasciata (Schrottky, 1913), and C. vogeli Roig-Alsina, 2000. The relationships among the subgenera of the "Centris group" were: (Xanthemisia (Penthemisia (Centris s. str. - Paracentris))). Centris xanthomelaena Moure & Castro 2001, an endemic species of the Caatinga and previously considered a C. (Paracentris), came out as the sister group of C. (Centris) s. str. A new species of C. (Paracentris) from Chile is described: Centris toroi sp. nov. Lectotypus designations and redescriptions are presented for Centris burgdorfi, C. caelebs, C. lyngbyei, C. tricolor, C. autrani Vachal, 1904 and C. smithii Friese, 1900. New synonyms proposed: C. buchholzi Herbst, 1918 = Centris wilmattae Cockerell, 1926 syn. nov.; C. caelebs Friese, 1900 = Paracentris fulvohirta Cameron, 1903. The female of C. vogeli Roig-Alsina, 2000 and the male of C. xanthomelaena are described.

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The genus Anthidium Fabricius in the South America: key for the species, descriptive notes, and geographical distribution (Hymenoptera, Megachilidae, Anthidiini). The Anthidiini, in South America, is represented by a single genus Anthidium Fabricius, 1804 (type-species: Apis manicata Linnaeus, 1758). Thirty nine species are treated in this paper, as follows: Anthidium alsinai Urban, 2001; A. andinum Joergensen, 1912; A. anurospilum Moure, 1957 nom. reval. (formerly = A. espinosai Ruiz, 1938); A. atricaudum Cockerell, 1926; A. aymara Toro & Rodríguez, 1998; A. chilense Spinola, 1851; A. chubuti Cockerell, 1910; A. colliguayanum Toro & Rojas, 1970; A. cuzcoense Schrottky, 1910; A. danieli Urban, 2001; A. decaspilum Moure, 1957; A. deceptum Smith, 1879; A. edwini Ruiz, 1935; A. espinosai Ruiz, 1938; A. falsificum Moure, 1957; A. friesei Cockerell, 1911; A. funereum Schletterer, 1890; A. garleppi Schrottky, 1910 = A. matucanense Cockerell, 1914 syn. nov.; A. gayi Spinola, 1851; A. igori Urban, 2001; A. larocai Urban, 1997; A. latum Schrottky, 1902; A. luizae Urban, 2001; A. manicatum (Linnaeus, 1758); A. masunariae Urban, 2001; A. nigerrimum Schrottky, 1910; A. paitense Cockerell, 1926; A. penai Moure, 1957; A. peruvianum Schrottky, 1910; A. rafaeli Urban, 2001; A. rozeni Urban, 2001; A. rubripes Friese, 1908 = A. boliviense Friese, 1920 syn. nov. = A. adriani Ruiz, 1935 syn. nov. = A. kuscheli Moure, 1957 syn. nov.; A. sanguinicaudum Schwarz, 1933; A. sertanicola Moure & Urban, 1964; A. tarsoi Urban, 2001; A. toro Urban. 2001; A. vigintiduopunctatum Friese, 1904; A. vigintipunctatum Friese, 1908, and A. weyrauchi Schwarz, 1943. Some taxonomic comments are made for each species, and new data on geographic distribution are also given. The females of A. andinum, A. igori, A. rozeni and the male of A. anurospilum are described for the first time. Identification keys (for males and females), as well as illustrations for almost all species, are provided.

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Systaltocerus platyrhinus Labram & Imhoff, 1840: redescriptions and considerations about the synonymy with Homalorhamphus vestitus Haedo Rossi & Viana, 1957 (Coleoptera, Anthribidae, Anthribinae). The genus Systaltocerus Labram & Imhoff, 1840 and the species S. platyrhinus Labram & Imhoff, 1840 (type species), are redescribed. Illustrations of the mouth pieces, endosternites, wing venation, male and female terminalia, and rectal plates, are given for the first time. New data on geographic distribution are also presented. Nomenclatural changes introduced: Systaltocerus Labram & Imhoff, 1840 = Homalorhamphus Haedo Rossi & Viana, 1957 syn. nov.; Systaltocerus platyrhinus Labram & Imhoff, 1840 = Homalorhamphus vestitus Haedo Rossi & Viana, 1957 syn. nov.

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Os processos de erosão hídrica em Cabo Verde são os mais marcantes da dinâmica actual das vertentes, pois são os mais comuns e que afectam áreas extensasdurante a curta estação húmida de três meses. A ocorrência de episódios chuvosos concentrados no tempo e com uma evidente irregularidade espacial permitem umaacentuada erosividade das precipitações, marcada por uma forte irregularidade regional. A forte variabilidade das formas de relevo, a diversidade da natureza das unidadesgeológicas e a multiplicidade de ocupação do solo favorecem condições deerodibilidade muito contrastadas no espaço. O objectivo deste trabalho é estabelecer um modelo desusceptibilidade à erosão hídricaem função de factores geomorfológicos (declive, perfil e traçado das vertentes eerodibilidade das unidades litológicas e dos materiais de cobertura), climáticos(intensidade pluviométrica) e de ocupação do solo para as bacias das ribeiras dos Picose Seca. Os resultados foram obtidos com recurso ao ambiente de Sistemas deInformação Geográfica (SIG). Este trabalho surge na sequência de outros já realizadospelos autores, onde se apresentaram as condições de erodibilidade e erosividade paraáreas mais restritas da Ilha de Santiago. O modelo de susceptibilidade à erosão hídrica resultou do cruzamento dos mapas dedeclives, de perfil e do traçado das vertentes, obtidos a partir do modelo digital deterreno (DTM), do mapa geológico, da distribuição espacial da intensidadepluviométrica e da densidade de ocupação do solo, tendo em conta que são estas asprincipais condicionantes de erosão hídrica, referidas pelos autores que estudaram estaregião. Cada um destes mapas foi reclassificado com base numa análise qualitativa dograu de erodibilidade, sendo atribuído um número de ordem a cada classe, em função da sua susceptibilidade à erosão hídrica, conforme foi localmente reconhecido. Verifica-se que as áreas de maior susceptibilidade à erosão hídrica são as do sectorsudeste da bacia da Ribeira Seca e as vertentes dos principais vales da bacia da Ribeira dos Picos, onde se encontram as unidades geológicas mais friáveis, os declives mais acentuados e onde predominam sectores das vertentes de traçado côncavo, a que seassocia pontualmente a mais elevada intensidade pluviométrica.

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On Gymnocerus Audinet-Serville, 1835 (Coleoptera, Cerambycidae, Lamiinae, Anisocerini) and related genera. The genus Gymnocerus Audinet-Serville, 1835 is characterized and a key to the related genera is added. New combinations: Gymnocerina cratosomoides (Bates, 1862), comb. nov. (from Gymnocerus) and Badenella gavisa (Lane, 1966), comb. nov. (from Chimboincola). New synonyms proposed: Badenella Lane, 1964 = Chimboincola Lane, 1966 syn. nov.; Gymnocerina cratosomoides (Bates, 1862) = Gymnocerus crassus Bates, 1862 syn. nov. = Gymnocerina sulfurea Lane, 1964 syn. nov. = Gymnocerina subsiciva Lane, 1964 syn. nov. = Gymnocerina spuria Lane, 1964 syn. nov. = Gymnocerina oliveirai Lane, 1964 syn. nov.; and Badenella badeni (Bates, 1875) = Gymnocerus badeni fuscus Franz, 1935 syn. nov. = Badenella laceyi Lane, 1964 syn. nov..