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1.
《Palaeoworld》2021,30(4):659-676
The lower/upper Emsian boundary witnessed prominent diversification of biostratigraphically important genera Polygnathus Hinde, Caudicriodus Bultynck, and Latericriodus Müller. In contrast, conodonts previously reported around this boundary from the South China Block were characterized by relatively low species or subspecies diversity, and only a few widely distributed and extensively studied zone-defining taxa were recorded. In this paper, conodonts from the Daliantang Formation at the Daliantang section (Guangnan, southeastern Yunnan), one of the representative sections of the transitional facies between the benthic Xiangzhou facies and the pelagic Nandan facies, are investigated. The conodont fauna shows a remarkably high species or subspecies diversity, with fourteen taxa that are assignable to the notoperbonus Zone and inversus Zone. Five polygnathid species are described: P. gronbergi Klapper and Jonson, P. inversus Klapper and Jonson, Polygnathus sp. B, P. luciae Martínez-Pérez and Valenzuela-Ríos, and P. mashkovae Bardashev. The latter two are reported for the first time from the South China Block. Additionally, three icriodontid taxa are also described, of which L. guangnanensis n. sp. is characterized by distinctly chevron-shaped transverse rows in the anterior part and a well-developed process branching off to the outer side. The new conodont record increases our understanding of the diversification and faunal composition around the lower/upper Emsian boundary in the South China Block. It contributes to the regional and inter-regional biostratigraphical correlation between shallower- and deeper-water facies and also furnishes important South China material for future discussion and deliberation on the position of the lower/upper Emsian boundary. 相似文献
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Manuel de la Estrella Francisco J. Cabezas Carlos Aedo Mauricio Velayos 《Folia Geobotanica》2010,45(1):1-57
This study provides a checklist of the Papilionoideae (Leguminosae) present in Equatorial Guinea, comprising 55 genera and 157 taxa. Twenty-six species are known from Annobón, 91 from Bioko and 110 from Río Muni. The best represented genus is Millettia with 14 species. Bibliographic references for Papilionoideae (Leguminosae) from Equatorial Guinea have been gathered and checked. Seventeen species are included, because published data on their distribution range suggests they may occur in Equatorial Guinea; 15 species are introduced and likely already naturalized; and 48 taxa are recorded for the first time from the country. This represents an increase of over 30% in the floristic knowledge of Papilionoideae from Equatorial Guinea. Three species only known from their types may be considered as endemic to Equatorial Guinea: Amphimas tessmannii, Leptoderris oxytropis and Millettia mildbraedii. 相似文献
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SANDRINE LADEVÈZE CHRISTIAN DE MUIZON 《Zoological Journal of the Linnean Society》2010,159(3):746-784
New metatherian petrosal bones from the mid to Late Palaeocene of Itaboraí, belonging to three morphotypes (VI, VII, and VII), are formally described and compared to fossil and extant taxa known by their auditory region. An attempt at assigning petrosal types to tooth‐based taxa from Itaboraí was made by combining parsimony and morphometric methods. The first large scale phylogenetic analysis of the Itaboraían metatherians, involving basicranial and dental characters in a larger number of taxa, is provided here and is at the basis of a systematic revision of the metatherians from Itaboraí. The combination of morphometric and cladistic analyses helps in understanding the affinities between the petrosals and the tooth‐based taxa. The metatherians from Itaboraí were taxonomically diverse, belonging to each of the most important radiations in marsupial evolutionary history (Didelphimorphia, Paucituberculata, Eometatheria). The inclusion of Palaeocene taxa in the crown group Marsupialia and above all in the Eometatheria radiation points to an early emergence of these clades in South America and corroborates the main molecular hypotheses. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 159 , 746–784. 相似文献
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《Cryptogamie Mycologie ☆》1999,20(2):79-90
Forty-seven taxa of Pyrenomycetes sensu lato from Almería, southern Spain, have been studied. The following are new records for the Spanish mycobiota: Capronia inconspicua, Comoclathris planispora, Diaporthopsis trinucleata, Eutypa consobrina, Eutypella kochiana, Montagnula longipes, Montagnula infernalis, Mycosphaerella nicotianae, Nectriella jucunda, Phaeosphaeria phragmitis, Pleospora dichromatricha, Pleospora rudis, Pleospora subalpina, Teichospora opuntiae and Trematosphaeria endoxyloides. Two new species are also described: Diademosa sabulosa and Phaeosphaeria rubescens. 相似文献
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《Geobios》2016,49(5):395-405
Geological explorations of the basal beds of the Río Yuca Formation (Tucupido region, Portuguesa State, western Venezuela) resulted in the recognition of a new vertebrate assemblage that includes eight taxa: the toxodont cf. Adinotherium, a Peltephilidae armadillo, the freshwaters fishes Platysilurus and Phractocephalus, the caiman Purussaurus, an indeterminate dolphin, turtles, and the previously recognized sloth Pseudoprepotherium venezuelanum. When compared with the higher latitudes faunas of Argentina and Chile, the presence of cf. Adinotherium and peltephilids in the Rio Yuca Formation is consistent, but not conclusive, with a Santacrucian to Frisian SALMA age. The associated fauna, as well recent apatite fission track analysis, indicates that the Río Yuca assemblage is more likely younger in age, specifically Middle to Late Miocene. So far, the Miocene localities of the northern part of South America have provided a less prolific fossil record compared to the southern part of the continent (e.g., Santacrucian and Friasian faunas of Patagonia), but the present work documents the surprising occurrence of two taxa (Peltephilidae and Nesodontinae) common in southern high latitude faunas of South America, implying the persistence of the Santacrucian-Friasian genus Adinotherium in younger strata from northern South America, and that peltephilids were much more widespread during the Miocene than previously recognized. The presence of these common Patagonian taxa (Peltephilidae and Nesodontinae) in Río Yuca also supports the hypothesis of prior researchers for the existence of biogeographical connections between the northern and southern portions of South America during the Late Oligocene or Early Miocene, which facilitated faunal interchange between the two regions. Finally, the biogeographical affinities of the freshwater fishes and the giant caiman (Purussaurus) indicate close relationships of the Tucupido region with the ancestral distribution of the Orinocoan–Amazonian drainage system. 相似文献
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The variation leaf constituents (mostly terpenoids) was analyzed from each of the taxa of Juniperus in Mexico and Guatemala by numerical taxonomic methods. These results were compared with those of a previous study utilizing morphological characters. In general, the two agree on the major groups. Differences between more closely related species were more apparent with the chemical data, whereas more distantly related taxa sometimes appeared to be more closely related chemically due to the presence of a single component such as α-pinene in high concentration in each of the oils. Four large groups are apparent; the deppeanan; flaccidan; monticolan; and the oneseeded (pinchotii) complex. Some taxa (J. durangensis, J. standleyi, J.jaliscana) are still of uncertain affinities. This study confirms the morphological data indicating that J. patoniana Martínez should be reduced to a variety of J. deppeana (J. deppeana var. patoniana (Martínez) Zanoni, comb. et stat. nov). No samplestypical of J. monosperma were found in Mexico and J. monosperma var. gracilis (sensu Martinez) was found to not be closely allied with J. monosperma from the USA but has some uncertain affinities with species of the one-seeded complex. These relationships need to be examined in more detail. J. blancoi appears to be closely related to J. scopulorum. This information on the junipers of Mexico and Guatemala should prove invaluable to future studies on the evolution of the Juniperus in North America. 相似文献
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A new genus and three new species of Figitinae (Hymenoptera: Figitidae) are described from Colombia: Ferpereira Pujade-Villar n. gen., Ferpereira fiorellae Pujade-Villar n. sp., Neralsia levis Pujade-Villar & Petersen-Silva n. sp., and Figites colombiensis Pujade-Villar & Paretas-Martínez n. sp., which is the first species of Figites Latreille from Colombia and the second from South America. The diagnostic characters of these new taxa are illustrated. 相似文献
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There are four terrestrial, above-ground stemmed Zamia taxa in Panama, the species delimitations of which have been a matter of controversy or misplacement at one time or the other (Schutzman et. al., 1998; Stevenson, 1993; Taylor, 1999a, b, 2002). All are allopatrically distributed. Two are in western Panama in Chiriquí province. One of these, Z. pseudomonticola, is found in the northwest of the province at altitudes above 1000 m, while the other, Z. fairchildiana, is found in a relatively small patch of forest in southwestern Chiriquí province. The other two taxa are found around the Canal area or farther east. The species described in this paper is found near the Canal area, and the last of the group, Z. elegantissima, occurs north of the Canal area in the province of Colon and also some distance to the east, including part of the Dule or Kuna aboriginal homeland known as Kuna Yala. After 16 years of research on the new taxon, we have decided to describe it as a new species, pointing out its similarity to Z. elegantissima and its distinctness from Z. pseudomonticola and Z . fairchildiana. The two western species are more alike in structure compared with the eastern species, and the latter are more alike between themselves compared to the western taxa. Even so, there are differences in vegetative and reproductive structures to clearly separate each species. There are even differences in the pollinators, these being, in all cases found, species of the weevil genus Rhopalotria and the snubbed-nosed beetle Pharaxonotha. 相似文献
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In northern Patagonia, riparian ecosystems are highly modified due to alien plant invasions. The establishment of non-native willows and poplars has unknown effects for Salix humboldtiana, the only native floodplain tree species in this region. To clarify establishment processes and to assess whether interspecific competition among the Salicaceae taxa may occur and therefore whether the native species can coexist in the long term, we analysed age structure and growth performances of the dominant four taxa within mixed adult forest stands along the Río Negro, Argentina. Low mean ages of <15 years for all four taxa within 20 stands could be detected and suggest frequent and severe disturbances resulting in the removal of existing vegetation and subsequent creation of sites for establishment. Trees of the same stand showed the same age structure indicating joint establishment events with all taxa involved. A significant better growth performance (basal area, crown diameter) could be proved for the invasive willows. Considering the upper and middle river separately in a total of 88 studied plots, S. humboldtiana was more frequent at the middle river stretch, while invasive willows showed an opposing pattern suggesting a downstream directed invasion process. The results showed that competition pressure in mature mixed stands could affect S. humboldtiana. However, these stands are usually removed by river dynamics creating new sediment bars and islands. These processes enable S. humboldtiana seeds to germinate frequently which may compensate for its inferior growth performance and potential impacts by the invasive willows and poplars. 相似文献
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During the pollen analyses of Bohemian peat and limnic sediments numerous empty cell walls of some chlorococcal algae, particulary, of the genusPediastrum, were found. This material was taxonomically determined and the ecology of different taxa was reconstructed and compared with the present one. The greatest difference was found inPediastrum integrum andP. kauraiskyi occurring commonly in Central Europe in the lakes during the Late-Glacial and Postglaciíal Periods but very rarely at present. Our results were compared with some data given in the literature. 相似文献
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Up-to-date results of taxonomic and phytogeographic studies ofOenothera subsect.Oenothera in the eastern part of the Czech Republic (Moravia and Silesia) are presented. A new hybridogenous species,Oe. moravica Jehlík etRostański (=Oe. fallax × Oe. victorini), is described from S Moravia. Several taxa and hybrids are reported for the first time for the Czech Republic:Oe. victorini Gates etCatcheside (=Oe. rostanskii Jehlík),Oe. × wienii Renner exRostański,Oe. acutifolia × Oe. victorini. Other taxa are recorded from the eastern part of the Czech Republic for the first time:Oe. acutifolia Rostański,Oe. hoelscheri Renner exRostański,Oe. parviflora L.,Oe. subterminalis Gates. The taxonomy ofOe. pycnocarpa Atkinson etBartlett is discussed. A survey of species and hybrids ofOenothera subsect.Oenothera in the Czech Republic is added. 相似文献
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《Journal of bryology》2013,35(2):461-493
AbstractThe bryophyte flora of the Sierras de Filabres, Cabrera, Alhamilla and Cabo de Gata of Almería province (S.E. Spain) includes 280 taxa (236 mosses and 44 liverworts) of which 74 are new to the province of Almería, 31 to the southeastern part of the Iberian Peninsula and 4 to the Iberian Peninsula. Data about their biogeography and ecology are given. 相似文献
17.
Aktivita sukcinát-dehydrogenázy SDH a sukcinát-oxydázového systému SO byla mě?ena sestý den po vyklí?ení v homogenátu z ko?en? klí?ních rostlin ho??ice, které byly pěstovány v ?ivném roztoku, obsahujícím některý ze t?í polohových isomer? fenethylpyridinu (IIIA, B, C) nebo pyridylfenylacetylenu (IVA, B, C) v koncentraci 5×10?4 m. Slou?eniny fenethylpyridinového typu prakticky neovlivňují aktivitu dehydrogenázy kyseliny jantarové SDH aniin vivo, aniin vitro, av?ak pyridylfenylacetyleny aktivitu tohoto enzymuin vivo výrazně stimulují. Naproti tomu oba typy slou?enin v pokusném uspo?ádání jakin vivo, takin vitro pr?kazně inhibují aktivitu sukcinát-oxydázového systému SO. Ú?inek fenethylpyridin? i pyridylfenylacetylen? je tedy pravým opakem ú?innosti trans-styrylpyridin? (typ I). 相似文献
18.
《Geobios》2020
Marly sediments of the early Messinian Abad Member of the Turre Formation from the northeastern sector of the Carboneras-Nijar Basin (southern Spain) have yielded a rich fossil assemblage, of which 60 taxa are documented herein. Besides nannoflora and microfauna, this assemblage includes the first autochthonous macrofauna described from the Abad Member. Based on the calcareous nannofossil assemblage, in particular the occurrence of the zonal index taxon Amaurolithus primus, the sediments are assigned to the Mediterranean calcareous nannofossil zone CNM17, corresponding to the latest Tortonian to earliest Messinian interval. This matches the age range generally reported for the Abad Member. Palaeoecological evidence from calcareous nannofossils (20 autochthonous taxa), planktic and benthic foraminifera (12 taxa), Porifera (3 taxa), Octocorallia (Keratoisis), Serpulidae (4 taxa), Bivalvia (5 taxa), Gastropoda (2 taxa), Brachiopoda (7 taxa), Cirripedia (Faxelepas) and Vertebrata (5 taxa) indicates an upper bathyal environment with an influx of neritic elements for the Abad Member near Carboneras. Additionally, several faunal components may represent allochthonous/parautochthonous elements from adjacent habitats, which were transported into the deep marine setting by turbiditic mass flows. Although similarities exist, the fossil assemblage from the marls is compositionally significantly different from the biota previously documented from a nearby exposed olistostrome, the ‘red breccia’. Similar fossil assemblages from the Mediterranean have so far mainly been reported from the Pliocene-Pleistocene of southern Italy and Greece. The Carboneras fauna thus adds to our knowledge of the development of these habitats and their biota prior to the Messinian salinity crisis. Beyond the novel palaeoenvironmental data, the range of the dyscoliid brachiopod Ceramisia meneghiniana, previously known only from the Pliocene of Italy, is extended to the Miocene of Spain. The cirripede crustacean Pycnolepas paronai De Alessandri, 1895 is transferred to the hitherto monospecific genus Faxelepas Gale, 2015, whereby the range of the latter (previously Maastrichtian to Danian) is extended to the late Miocene. 相似文献
19.
Haibo Wan Christopher J. Chizinski Christine L. Dolph Bruce Vondracek Bruce N. Wilson 《Ecological Indicators》2010,10(4):781-788
The index of biotic integrity (IBI) is a commonly used bioassessment tool that integrates abundance and richness measures to assess water quality. In developing IBIs that are both responsive to human disturbance and resistant to natural variability and sampling error, water managers must decide how to weigh information about rare and abundant taxa, which in turn requires an understanding of the sensitivity of indices to rare taxa. Herein, we investigated the influence of rare fish taxa (within the lower 5% of rank abundance curves) on IBI metric and total scores for stream sites in two of Minnesota's major river basins, the St. Croix (n = 293 site visits) and Upper Mississippi (n = 210 site visits). We artificially removed rare taxa from biological samples by (1) separately excluding each individual taxon that fell within the lower 5% of rank abundance curves; (2) simultaneously excluding all taxa that had an abundance of one (singletons) or two (doubletons); and (3) simultaneously excluding all taxa that fell within the lower 5% of rank abundance curves. We then compared IBI metric and total scores before and after removal of rare taxa using the normalized root mean square error (nRMSE) and regression analysis. The difference in IBI metric and total scores increased as more taxa were removed. Moreover, when multiple rare taxa were removed, the nRMSE was related to sample abundance and to total taxa richness, with greater nRMSE observed in samples with a larger number of taxa or sample abundance. Metrics based on relative abundance of fish taxa were less sensitive to the loss of rare taxa, whereas those based on taxa richness were more sensitive, because taxa richness metrics give more weight to rare taxa compared to the relative abundance metrics. 相似文献
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Sula E. Vanderplank Jon P. Rebman Exequiel Ezcurra 《Biodiversity and Conservation》2018,27(1):109-122
Six regions of northwestern (NW) Baja California (Sierra de Juárez, Sierra de San Pedro Mártir, Punta Banda, Colonet, San Quintín and Valle Tranquilo) were compared for their floristic diversity. Checklists for each region were analyzed by their total, native, and endemic floras to give measures of floristic similarity and overlap, and to identify the strongest gradients affecting species distributions. Each region was floristically distinct, with significant variation in the distribution of state endemic taxa. The six regions are readily differentiated by their geographical position in a Principal Components Analysis. The strongest gradients were (a) the W–E gradient from the coast to the mountains and (b) the latitudinal gradient from N to S. These six adjacent regions are found within a local and global biodiversity hotspot that is subject to intense conservation challenges. Conservation of many areas is essential to adequately preserve the diversity of locally endemic taxa with restricted ranges, yet the coast lacks any protected areas at the state and federal level. Private reserves such as Reserva Natural San Quintín may be critical to the conservation of regionally endemic taxa. 相似文献