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61.
该文在研究标本和文献的基础上,介绍河南省连康山自然保护区所产的光萼苔科(Porellaceae)植物2属8种,即光萼苔属Porella(7种)和多瓣苔属Macvicaria(1种)。讨论了它们的生境、识别特征和植物区系地理成分,并编制了河南省连康山自然保护区光萼苔科植物的分属、分种检索表。 相似文献
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The base of the Clun Forest Formation at Clun, Shropshire, has previously been taken to correlate with the base of the Downton Castle Sandstone Formation (Přídolí Series, upper Silurian) on the basis of brachiopod, bivalve, gastropod and ostracod faunas. The detailed distribution of microfossils (acritarchs, chitinozoans, conodonts and ostracods) is documented at Nantyrhynau Quarry, Clun, Shropshire, to test this correlation. Three new species of chitinozoans, Eisenackitina clunensis, Eisenackitina kerria and Angochitina paucispinosa, are described from the quarry. Macrofossil and ostracod distributions suggest that the correlation is correct. However, a typical Ludlow acritarch flora is present throughout the section and suggests that the basal part of the Clun Forest Formation is Ludlow in age. The mixture of characteristic Ludlow and Přídolí microfossils at Nantyrhynau Quarry may be the result of differing environmental conditions between the Ludlow (shelf) and Clun (basinal) areas at this time. Alternatively, the strata exposed at Nantyrhynau Quarry may represent a period towards the end of the Ludlow Series when there are no strata represented in corresponding shelf sections due to non-deposition or erosion. © 1997 John Wiley & Sons, Ltd. 相似文献
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匹配系数聚类分析在Pseudozaphrentis属分类中的应用 总被引:2,自引:0,他引:2
摘要:Pseudozaphrentis属分布广泛,有重要的地层意义,但关于其分类位置、范围及种的划分争论较大.本文在匹配系数统计分析的基础上,对Pseudozaphrentis属的下列3个方面予以讨论:1.探讨属之间的亲缘关系,确定属的分类位迂.Pseudozaphreatis与相近属的对比表明其与Charactophyllum-属的匹配系数最高,它们之间的关系可能最为相近.因此把二者归入属以上的同一最低分类单元—Charactophyllinae亚科.2.确定属的范围.根据统计结果得到的代表性特征组简单而准确地定义属.3.合理地划分种.Pseudozaphreatis-属可分为4个种:PseudozaphrentisdifficileSun,19581;NeostringophyllumproniniSoshkina,1951;Pseudozaphrentiscf.wangchenpoensisYuetLiaoinJinetal.,1982;PseudozaphnytisxipingshanensisX.L.Wang,1987. 相似文献
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For the first time, ichthyoliths are described from the Santos sedimentary basin, offshore southern Brazil. Isolated teeth, dermal scales and the first documented otoliths from Cretaceous (Albian) to Recent cuttings from five wells are described. The following groups are represented: Chondrichthyans: Triakidae, Carcharhinidae; Ginglymostomatidae: ?Ginglymostoma sp., Lamnidae indet., Scyliorhinidae; Osteichthyans: Teleostei; Myctophiidae: Diaphus aff. splendidus sp. complex, Diaphus spp., Diaphus cf. garmani, Ceratoscopelus aff. warmingii; Sternoptychidae: Valenciennellus tripunctulatus, teeth of indeterminate Teleostei. The majority of these ichthyofossils represent extant forms, known to occur in the Atlantic Ocean, and are of potential value for stratigraphical correlations between oil‐yielding basins in the region. Ostracods are not well preserved but can be identified to generic level indicating marine environments. The ostracod faunas offer potential for intrabasinal correlation in the Eocene and Oligocene. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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《Limnologica》2020
Niphargus puteanus is the oldest described species of its genus and, in the past, was used as a taxonomic annotation for any subterranean amphipod record. For that reason, no clear knowledge exists about its actual range size and habitat preferences. We here applied a molecular taxonomic and phylogeographical approach based on mitochondrial and nuclear DNA to shed light on its distribution and to infer its demographic history. Furthermore, we analysed aquifer types and water flow regimes to provide a clearer picture of the species’ ecological requirements.Our results indicate that N. puteanus is widely distributed north of the Alps, having its core range in the geomorphological natural region of the ‘South German Scarplands’ (SGS). Additionally, isolated satellite populations exist in the Taunus and the Sauerland, and two single individuals were collected in Luxembourg and in Austria, respectively. The species’ maximal distribution range reaches 756 km between the two single-specimen records and 371 km within the SGS. A very high haplotype diversity was observed, revealing the presence of seven haplotype groups. All the haplogroups were present in the SGS and exhibited distinct spatial-genetic patterns. We thus inferred a high degree of population isolation, with the SGS being a potential long-term refugium for N. puteanus. Historical drift of specimens along major riverine networks (Rhine, Danube) may provide an evolutionary dispersal mechanism explaining the formation of satellite populations.From an ecological perspective, populations of N. puteanus were found to be closely associated with fast-flowing spring environments within fissured aquifers. This species should therefore be classified as both crenophile and stygophile, effectively exploiting resources of surface as well as subsurface spring waters. 相似文献
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China Seas are one of the most diverse regions in the Pacific. Though much eff ort has been made to explore its biodiversity, the polychaetes diversity is still poorly known. A large number of species records are based on ecological investigation rather than taxonomical studies. We update the Polychaete species taxonomicaly described from China coastal waters during 2008–2017 and list them as a catalogue. The catalogue contains 47 species of 32 genera and 17 families, the type depository, type locality and geographic distribution. Some taxonomic problems are present in remarks. 相似文献
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A new species belonging to the genus Haloschizopera Lang, 1944 (Copepoda, Harpacticoida, Miraciidae, Diosaccinae) was identifi ed based on the samples collected from the East China Sea, near the off shore of Zhejiang Province, East China. The new species is closely related to H . pygmaea Norman & Sccot T., 1905 and shares a combination of the following features: A1 eight-segmented;A2 exp-2 with one distal seta, exp-3 with three setae;P1 endopodal segments subequal, enp-1 not exceeding exp-2;exp-3 of P3 with one inner seta, of P4 with two inner setae. The new species is characterized by the presence of one inner seta on P2 exp-3 of both sexes. It can also be distinguished from its congeners by the characters of female: P5 exopod subcircular, endopodal lobe extending beyond half-length of exopod;genital doublesomite ornamented with three dorsolateral rows of spinules on anterior part. 相似文献