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1.
The intertidal seaweed flora of Isipingo Beach, Natal, is described. Isipingo Beach lies on the sub-tropical east coast of southern Africa and is the only east coast locality studied in detail by pioneering biogeographers. A total of 172 species (37 chlorophytes, 26 phaeophytes and 109 rhodophytes) are recorded. A phycogeographical analysis of 124 species with sufficiently documented distributions, shows that 69% are warm water species also known from the tropical coasts of Mozambique, Tanzania and Kenya. The phycogeographical affinity of the Isipingo flora is certainly with sub-tropical and tropical floras.  相似文献   

2.
Upper Cretaceous plant impressions from the reddish gray sandy and clayey deposits of the Zhirkindek Formation of the Karakumzholy locality (the Lower Syr Darya Uplift, Kazakhstan) were studied. This Turonian flora includes two species of fern (Filices) and several angiosperm species. The angiosperms Ettingshausenia cuneifolia (Bronn) Stiehler (described previously as Platanus cuneifolia Bronn) and Trochodendroides arctica (Heer) Berry dominate at the locality. The former species is a typical representative of the Upper Cretaceous flora of the Euro-Sinian subtropical phytogeographic region of Eurasia, while the latter belongs to the temperate Siberian-Canadian phytogeographic region.  相似文献   

3.
In this paper the collection and analysis of a sample of moths made on an altitude transect on Mt. Kinabalu, Sabah, are described. The geological and phytogeographical histories of the mountain are reviewed. Single-link cluster analysis is used to pick out faunal elements in the transect. The geographical affinities of the species composing these elements are investigated and discussed.
As with the flora, species in the lowland elements belong largely to centric groups (with centres of speciation coincident with the locality concerned) of the south-east Asian rain forest regions. Increasingly higher elements have an increasing representation of species from eccentric groups. In the flora these eccentric groups are Himalayan and south temperate in roughly equal proportions. In the moth (and bird) fauna they are almost entirely Himalayan centred.
Distribution of montane habitats during the Pleistocene glaciations favoured the colonization of Kinabalu from sources to the south-east. An explanation is presented for the contrast between flora and moth fauna on Kinabalu in terms of the relative development of these groups in the two source areas.  相似文献   

4.
The diatom flora in the lower Damour River, a small coastal river in Lebanon, was studied during 1981. The study area included the Damour estuary and a tributary, the el-Hamam River. Achnanthes minutissima was the most abundant diatom in the flora. Other dominant taxa included Nitzschia dissipata and Navicula cryptocephala var. veneta in the spring and Anomoeoneis vitrea in the fall. The diatom community structure was characterized by 1 or 2 dominant taxa, a few common and many rare taxa, but the taxa in these categories varied according to season and locality. The freshwater flora had a group of 20 taxa which were widely distributed in the study area throughout the study period. These taxa, in addition to a few taxa of more restricted seasonal occurrence, were the major contributers to the flora and are characteristic of this river system. Certain aspects of the flora were resistant to change. Others were more sensitive to environmental conditions. The estuarine flora reflected brackish conditions beginning in June and extending through October.  相似文献   

5.
A late Wenlock flora from Co. Tipperary, Ireland   总被引:1,自引:0,他引:1  
An assemblage of macroplants preserved as highly coalified compressions which lack anatomy is described from a Wenlock locality in County Tipperary, Ireland. Most of the fertile specimens are assigned to Cooksonia Lang. The taxonomic status of this genus is discussed. Some poorly preserved palynomorphs, including miospores, acritarchs, chitinozoans and a variety of tubes, have been isolated from associated sediments, but the age of the flora is based on graptolites. Sedimentological and palaeontological studies of the region are summarized. They provide little direct evidence for the habitats of the plants which are considered to have been terrestrial. The relevance of this flora to the current debate on the colonization of the land is evaluated and it is concluded that these plants provide the earliest record of erect fertile land plants of possible pteridophyte affinity.  相似文献   

6.
贡嘎山蕨类植物区系的特点   总被引:7,自引:1,他引:7  
贡嘎山蕨类植物区系共含40科,93属,399种,最主要的是耳蕨属Polystichum,鳞毛蕨属Dryopteris,蹄盖蕨属Athyrium以及水龙骨科Polypodiaceae等系统演化上较高级的类群,所含的种子是喜马拉雅和中国西南当地分化的种;其特有成分多为新特有属,可认为它是随青藏高原隆起而形成的较年青的蕨类区系,热带属在本区数量多而种类少,在山上河可与北温带种类并存。贡嘎山处于蕨类物种东  相似文献   

7.
M. Brunet  Y. Jehenne  M. Ringeade 《Geobios》1977,10(1):109-112
The new locality of Ruch (Gironde), from a lateral facies of the “Calcaire de Castillon” formation has yielded an important flora and fauna. From the biostratigraphic point of view the mammalian fauna allows to show that Ruch is contemporaneous of the reference locality of Ronzon (Auvergne).  相似文献   

8.
本文描述了贵州金沙岩孔镇长岩沟下寒武统(纽芬兰统—寒武系第2统)牛蹄塘组底部黑色页岩中呈碳质薄膜保存的宏观藻类化石,共3属3种:美丽遵义藻Zunyiphyton pereleganus Yang et Zhao,1999,云南中华细丝藻Sinocylindra yunnanensis Chen et Erdtmann,1991,文德带藻(未定种)Vendotaenia sp.。该组合中主要分子是Zunyiphyton pereleganus和Vendotaenia sp.,它们也是遵义牛蹄塘组宏观藻类组合中最主要的分子。而遵义牛蹄塘组宏观藻类组合的另一特征分子贵州约克那斯藻Yuknessis guizhouensis及底栖固着型藻束状陡山沱藻Doushantuophyton comet在金沙岩孔牛蹄塘组宏观藻类化石组合中未见,说明产于浅水台地的牛蹄塘生物群宏观藻类组合既具有广泛的一致性也具有一定的差异性。  相似文献   

9.
The Anticlinorium of Huayacocotla has several outcrops of geological and paleontological importance. However, reports of localities with paleoflora have been scarce so far. In this study, we report three new localities in the Cisuralian, the diversity and composition of which lead us to propose that the paleoflora may have been derived from vegetation that grew in an arid environment with seasonal wetness. The plant remains from the localities of Papaxtla and Calnali are highly transported and their diversity indicates the presence of several groups of plants that were shared with the La Virgen locality, which yielded the best preserved plant fossils. Changes in paleoenvironmental conditions indicate that the preservation of the flora was affected by the tectonic evolution of the region associated with sea level changes. The data presented here increase our knowledge of both the Cisuralian fossil flora and paleoenvironment in the south-central region of the Huayacocotla Anticlinorium, Hidalgo state.  相似文献   

10.
From the Upper Jurassic flora of Andöya, Northern Norway, which is now under revision, Pseudotorellia heeri sp. nov. is described on cuticular characters. It has been shown that some specimens previously described by Heer as Baiera pulchella and Phoenicopsis latior from the same locality belong to the new species.  相似文献   

11.
《Comptes Rendus Palevol》2014,13(5):421-441
The paralic flora and fauna from the Late Jurassic of Chassiron (Oléron Island, western France) are described. The Tithonian-aged bonebeds of Purbeck facies of this locality have yielded a rich and diverse vertebrate assemblage including fishes, amphibians, reptiles and mammals, alongside numerous plant and invertebrate remains. The Chassiron locality thus appears as a peculiar Konzentrat-Lagerstätte in which most of the palaeoecosystem's biological components (both aquatic and terrestrial) have been preserved. The depositional environment was probably subject to salinity fluctuations, as indicated by the co-occurrence of freshwater and euryhaline organisms. This is one of the richest localities and the first mammal-bearing site known from the Jurassic of France.  相似文献   

12.
王怿  朱祥根 《古生物学报》2020,59(2):192-197
中泥盆世晚期陆生植物的演化已经达到相当高的水平,我国以云南中泥盆世晚期植物群为代表,称为Lepidodendropsis arborecense-Minarodendron cathaysiense-Eocladoxylou minutum (LME)组合。当前在云南武定中泥盆世晚期地层(西冲组上部)中发现的植物主要有Lepidodendropsis arborescense,Eocladoxylon minutu,Rhipidophyton acanthum等,其中,在R.acanthum的茎干基部密集共生有腹足动物Valvata sp.。根据植物表面无动物咬食痕迹,以及腹足动物生态特性和演化分析,当前陆生植物与水生动物共生的原因是植物茎干飘落水体后,为水生的腹足动物提供了新的栖息场所,并随水流、风浪载运至异地埋藏。这种水生腹足动物寄栖于水中物体的生活方式很普遍,是腹足动物迁徙、扩散的一种重要途径。  相似文献   

13.
Summary The moorland pools in the region of the SE of Oisterwijk have an established reputation among Dutch hydrobiologists. This fame is to a large extent attributable to the extensive surveys of the desmid flora by Professor J. Heimans in the period between 1916 and 1925. His studies revealed an exceptional opulence of this algal group viz., a total of 250 species among which quite a number not recorded from any other locality in the Netherlands and also to be included among the rarities in a larger geographical region.  相似文献   

14.
澄清植物种类是植物分类学研究的基础,也是开展iFlora编研的前提,而植物物种调查则为其提供了最为基础和重要的研究素材。传统的植物物种调查,或以植物区系调查为目的,或是专类植物资源搜集.往往较为忽视种群层面的调查。iFlora计划中,基于地方种群的植物物种调查应予以重视和贯彻实施。系统的植物物种调查将以“个体(标本)一(地方繁育)种群一物种”为核心展开,其中地方繁育种群是调查的中心环节。调查内容将兼顾种群的形态学、生态学和遗传学三方面的学科需求,以期获得全面详实的物种数据,并藉此建立一套完整规范的物种“档案”。在整个植物物种调查中,“模式产地种群”是关注的重点,需制定缜密的调查方案并优先实施。由于模式标本的残缺、原始描述的简略,在未来的物种分类研究中,植物分类学者必须认真考虑“产地模式标本”和“模式产地种群”所扮演的重要角色。作为自然界中客观存在的群体,“模式产地种群”不仅仅是模式标本的注脚和补充,它犹如地质学上的“金钉子”.将为研究者提供最为权威和充分的形态学、生态学和遗传学等研究信息,从而真正将物种分类研究从“故纸堆”的困境中解放出来。  相似文献   

15.
An assemblage of 33 fossil pollen and spores, recovered from the 3600-m high Pislepampa locality of E. W. Berry, Eastern Cordillera, Bolivia, adds considerably to our knowledge of three aspects of the region in late Neogene time: (1) the paleovegetation, (2) the paleoclimate, and (3) the paleoelevation of the Central Andes. The plant microfossils recognized are Isoetes, Lycopodium (three types), Cnemidaria, Cyathea (three types), Grammitis, Hymenophyllum, Pteris, trilete fern spores (two types), Danaea, monolete fern spores (four types), Podocarpus, Gramineae, Palmae, Ilex, cf. Oreopanax, Cavanillesia, cf. Pereskia, Compositae (three types), Ericaceae, Tetrorchidium, and unknowns (three types). The diversity of the Compositae suggest that this flora has a maximum age around the Miocene-Pliocene boundary, that is, 6-7 million years. All members of the paleocommunity presently grow in the bosque montano húmedo (cloud forest) along the eastern slope of the Central Andes of Bolivia, which occurs between MATs (mean annual temperatures) of ~10° and 20°C. The Pislepampa flora probably represents the lower limits of this forest because the fossil leaves collected by Berry from the same locality all have entire margins, suggesting that the flora grew near the cloud forest-tropical forest transition. Presently, the lower limit of the cloud forest forest has MATs of ~20°C, a mean annual precipitation between 1000 and 1500 mm, and that part containing most of the identified genera of fossil pollen is found at elevations ~1200-1400 m. These conditions are thus inferred for the Pislepampa flora; however, because of the uncertainty of the magnitude of global climate change and of possible changes in the ecological range of plant genera, we estimate an error of at least ±1000 m for the paleoelevation estimate. When the total uplift is corrected for probable amounts of erosionally driven isostatic rebound, the paleoelevation estimate suggests that from one-third to one-half of the uplift of the Eastern Cordillera had occurred by the beginning of the Pliocene. This estimate is consistent with other paleoelevation estimates from the Central Andes.  相似文献   

16.
Radek Mikuláš  Ilja Pek 《Ichnos》2013,20(4):219-228
Old collections of the Upper Cretaceous flora at Maletín yield examples of trace fossils of plant‐arthropod interactions, comparable with recent insect galls. Grooves and ridges, often preserved on leaves at this locality, are (in contradiction to several previous authors) interpreted as traces of burrowing organisms, which originated in soft sediment adjacent to the plant remains lying on a lake floor or buried in the substrate. The leaves functioned in the sediment at the time of burrowing and/or during compaction of the substrate as distinctive laminar bodies with specific physical characteristics and therefore they enabled the preservation of some aspects of ichnofabric otherwise invisible in the surrounding strata.  相似文献   

17.
The Aleksandrovskoe locality (Krasnoufimsk district of the Sverdlovsk Region, Fore-Urals; Lower Permian, Kungurian Stage, Koshelevsk Formation), its taphonomy and taxonomic composition of the fossil flora are discussed. A new lycopsid, Ufadendron ufaensis gen. et sp. nov., with well-developed infrafoliar aerenchyma is described. The new plant is morphologically similar to the group of Early Carboniferous Central Angaran lycopsids (Tomiodendron Radczenko emend. S. Meyen, Lophiodendron Zalessky emend. S. Meyen, Angarophloios S. Meyen). Survival of a relic lycopsid of Central Angaran type with infrafoliar aerenchyma at the periphery of Angaraland up to the mid-Permian is discussed in terms of the “Lazarus taxa” phenomenon.  相似文献   

18.
A collection of over 200 petrified Middle Devonian plants was made from a single locality near Cairo, New York. This paper represents the second of a series enumerating the plants of the flora. Reimannia aldenense with a single lateral appendage containing a terete xylem strand that divides is present. Reimannia is thought to represent young branches within the Aneurophytales. Many of the sections made for the study of the flora contain small, terete axes. Some have a very distinctive epidermis. Some dichotomize several times. Cairoa lamanekii gen. et sp. n. shows closest affinity to the Aneurophytales yet differs in that the shape of the primary xylem is not consistently repeated from one order of axis to the next. It is suggested that Cairoa and Proteokalon represent a distinctive subgroup in the Aneurophytales.  相似文献   

19.
The new fossil locality of El Kohol is located on the southern flank of the Saharan Altas, near Brezina (Algeria). It has been discovered in a thick Palaeogene continental series divided into 4 members: a transitional gypsiferous member, a lower red detritic member, a middle marly-calcareous member, and an upper red detritic member. The new flora and fauna have been obtained by excavation and washing-screening of a marly level of the middle member. The main finds are charophytes, lower vertebrates, a marsupial and eutherian mammals (lipotyphlan Insectivora, hyracoids, creodonts and Proboscidea). Geological and palaeontological data allow to refer these fossil remains, at least provisorily, to the end of the early Eocene. Palaeobiogeographical comments are made about forms with Holarctic affinities.  相似文献   

20.
Abstract: Rögla is the northernmost locality yielding Mesozoic plant fossils in Scania, southern Sweden, and is one of the northernmost Rhaetian assemblages in Europe. The assemblage consists of over 500 specimens collected 50–60 years ago, of which 139 yielded identifiable plant remains referable to 15 plant species; another 19 specimens are tentatively assigned to four species because of their fragmentary preservation. The flora includes sphenophytes, ferns, cycads, bennettitaleans, seed ferns of uncertain alliance, conifers and some leaf remains that are tentatively assigned to ginkgophytes based on their epidermal anatomy. The species‐level composition of the assemblage is consistent with a Rhaetian age and is similar to well‐known floras from nearby Höganäs and Bjuv, except for the absence of cycads belonging to Nilssonia, which are very common in most other Scanian floras. The fossil assemblage is interpreted to derive from multi‐storey vegetation occupying moist habitats on a coastal plain. Strong affinities are evident with the coeval floras of Jameson Land, Greenland, reinforcing the concept of a distinctive North Atlantic floristic sub‐province at the close of the Triassic.  相似文献   

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