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This paper deals with some Middle Jurassic fossil plants from southern margin of the Eerduosi Basin. There are 36 species in 13 genus in this flora, i.e. Equisetum multi- dentatus Oishi, E. sp., Coniopteris hymenophylloides (Brongn.) Seward, C. bella Harris, C, burejensis (Zalessky) Seward, C. szeiana Choweet Yeh, C. tatungensis Sze, C. spp., Todites williamsoni (Brongn.) Seward, T. cf. williamsoni (Brongn.) Seward, Cladophle- bis asiatica Chow et Yeh, C. argutula (Heer) Fontaine, C. hsiehiana Sze, C. ( Gleichenites) takeyamae Oishi et Takahasi, C. cf. gracils Sze C. triangularis Oishi, C. grabauiana P’an C. cf punctata (Thoms) Chow et Yeh, C. spp., Baiera cf. concinna (Heer) Kawasaki, B. furcata (L. et H.) Braun, B. sp., Sphenobaiera longifolia (Pomel) Florin, Ginkgo obrutchewi Seward, G. sp., Phoenicopsis angustifolia Heer P. manchurica (Yo- koyama) Yabe, p. sp., Czekanowskia rigida Heer, C. sp., Pterphyllum sp., Elatocladus cf manchurica (Yokoyama) Yabe, E. sp., Podozamites lanceolatus (L. et. H.) Braun P. sp., Carpolithus sp. etc. The dominant groups of this flora are Filicopsida and Ginkgopsida. So it could be compared with the flora of Yanan Formation from inner Earduosi Basin and other floras from Northeast, Northwest and China, such as the floras of Dutung, Mentougon and Dongsheng etc. This flora is different from the Late Triassic flora and the Early Jurassic flora of North China. It belongs to the Coniopteris-Phoenicopsis flo- ra, which was assigned to Early-Middle Jurassic flora by Prof. Sze. But after studying, the authers believe that this flora should belong to Middle Jurassic rather than Early Jurassic. The climate was warm and damp in that time in North China.  相似文献   

3.
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   

4.
Abstract:  The Carnian (Late Triassic) flora of Lunz in Lower Austria is famous for an abundance of well-preserved bennettitalean and cycadalean foliage and reproductive structures. However, only the fertile remains have been studied in detail to date. Recently completed systematic macromorphological and cuticular analyses of leaf fossils from Lunz revealed that several forms previously accommodated in the genus Macrotaeniopteris do not represent ferns but rather Bennettitales assignable to the genus Nilssoniopteris . We describe three species of Nilssoniopteris , which represent the first records for this genus from Lunz, and one of the earliest accounts of Nilssoniopteris in the Northern Hemisphere. The following new combinations are introduced: Nilssoniopteris haidingeri (Stur ex Krasser, 1909 a ) comb. nov., N. angustior (Stur ex Krasser, 1909 a ) comb. nov. and N. lunzensis (Stur ex Krasser, 1909 a ) comb. nov. The discovery of Nilssoniopteris further substantiates the significance of the Lunz flora as one of the richest and most diverse early Late Triassic floras from the Northern Hemisphere.  相似文献   

5.
曹正尧 《古生物学报》2001,40(2):214-218
报道辽西义县组两种颇具地层意义的植物化石。Ruffordia goeppertii(Dunker)Seward和Nageiopsis exgr.samioides(Fontaine)berry,根据植物化石认为义县组的时代应属于早白垩世。  相似文献   

6.
新疆准噶尔盆地白杨河中侏罗世植物化石新材料   总被引:3,自引:0,他引:3  
苗雨雁 《古生物学报》2005,44(4):517-534
系统描述了准噶尔盆地西北缘白杨河地区西山窑组植物化石15属25种,首次在新疆地区发现侏罗纪真蕨类重要分子Coniopteris hymenophylloides的原位孢子及其孢子囊群,并对Phoenicopsis ( Phoenicopsis) an-gustifolia的叶角质层进行了研究。白杨河地区西山窑组迄今已知植物化石24属39种,以富含蕨类、茨康类、银杏类及松柏类,少见苏铁类等为特征,属于较为典型的内陆型、温带或暖温带植物群;其时代为中侏罗世,且可能为中侏罗世早期。该植物群应属于欧亚大陆早、中侏罗世植物地理区系中的西伯利亚区,反映了温暖潮湿、具季节性变化、并有利成煤的环境。  相似文献   

7.
In this paper Some Bennettitean leaves from the Lias of Karmozd-Zirab, Northern Iran, the author describes some Ptilophyllum species from a rich assemblage of Jurassic plants, collected by him in 1960 and 1961. The species axe Ptilophyllum bengalense (Oldh.) Schimper, P. harrisianum sp.nov., P. zirabense sp. nov., andP. minor sp. nov.  相似文献   

8.
本文对甘肃宝积山盆地中侏罗世植物群地质时代及植物区系进行了探讨, 共统计植物大化石 18 属 53 种, 主要包括银杏纲 10 属 24 种, 真蕨纲 5 属 22 种, 苏铁纲 1 属 3 种, 松柏纲 1 属 2 种, 楔叶纲 1 属 2 种。该植物群在组成特征上表现为银杏类、真蕨类植物繁盛, 其他植物类群相对贫乏。基于该植物群特征与国内其他植物群的对比, 提出其地质时代为中侏罗世 Aalenian 期–Bajocian 期。通过哈曼、欧式距离、罗杰斯–塔尼莫特和索卡尔–施尼斯 4 种方法对宝积山盆地及中国北方其余 11 个中侏罗世植物群进行系统聚类分析, 在此基础上进一步划分了中国北方植物区系。通过计算属、种相似性系数,探讨宝积山邻近植物区系间的亲缘关系, 结果表明宝积山植物区系与同属西北地区的华亭植物区系关系较为亲近。  相似文献   

9.
湘西–鄂西地区具有中–晚奥陶世连续过渡、出露良好的地层序列, 并产出大量头足类化石。我们选择了位于该地区的湖北宜昌陈家河剖面和湖南桃源茅草铺剖面开展头足类研究工作, 采集化石标本1000余块, 鉴定出了24属46种。本文描述了其中6个新种, 归属于3目3科5属。在中–晚奥陶世头足类动物群研究基础上, 本文在湖北宜昌陈家河剖面宝塔组和临湘组自下而上识别出Sinoceras chinense带和Richardsonoceras simplex带两个头足类化石带; 在湖南桃源茅草铺剖面牯牛潭组、大田坝组和宝塔组下部识别出4个头足类化石带, 自下而上分别是Proterovaginoceras incognitum带、Ancistroceras undulatum带、Cyclolituites带以及Sinoceras chinense带。在此基础上, 结合前人已发表的数据, 本文厘定了中扬子地区牯牛潭组到宝塔组的5个头足类化石带, 自下而上分别是: Proterovaginoceras incognitum带、Meitanoceras-Ancistroceras带、Lituites–Cyclolituites带、Sinoceras chinense 带和Richardsonoceras simplex带, 为该地区生物地层划分对比提供了头足类信息。  相似文献   

10.
Silicified coniferous wood was collected from the Lanqi Formation (late Middle Jurassic in age) at Shebudaigou Village, Liaoning Province, China. Three taxa are identified, namely Pinoxylon dacotense Knowlton, Xenoxylon phyllocladoides Gothan, and Araucariopitys sp. Based on these new data, and those of other fossil plants reported previously from the same formation, we consider the climate during the deposition of the Lanqi Formation was subtropical, humid and seasonal. In this respect the Lanqi flora differs from the coeval Shimengou and Longmen floras from North China. The Longmen flora was deposited during more humid, subtropical conditions, while the Shimengou Formation indicates that the climate was warm temperate and dry. Our data would suggest that the Late Jurassic climatic pattern was initiated as early as the late Middle Jurassic.  相似文献   

11.
The fossil plants described and illustrated were collected from the Yangshan Formation in Shangcheng and Gushi districts of southeastern part of Henan Province, namely, Lepidodendron cf. aolungpylukense Sze, L. shanyangense Wu et He, L. . cf. subrhombicum Gu et Zhi, L. sp. a, L. sp. b, Bothrodendron sp. a, B. sp. b, Lepidostrobus ? sp., Stigmaria ficoides (Sternberg) Brongniart, Archaeocalamites scrobiculatus (Schlotheim) Seward, Cardiopteridium spetsbergense Nathorst, Triph yllopteris ? sp., Rhodeopteridium hsianghsiangense (Sze) Zhang, Zhao et Wu, Paripteris cf. pseudogigantea (Potonie) Gothan, P. ? sp., Cordaites schenkii Halle, Cardiocarpus cordai (Geinitz) Gu et Zhi and Carpolithus sp., including 18 species in 11 genera. They belonged to Lycopsida, Sphenopsida, Filices, Pteridospermopsida, Cordaitopsida and Semina Gymnospermarum respectively , in which Lepidophytic plants of Lycopsida were the dominanance. The Yangshan Formation flora contains some typical Early Carboniferous elements, such as Archaeocalamites scrobiculatus, Cardiopteridium spetsbergense and Rhodeopteridium hsianghsiangense, which were fairly common from Visean to early Namurian; however, it also includes certain lepidophytic plants of the Cathaysian type, such as Lepidodendron cf. aolungpylukense, L. shanyangense and L. cf. subrhombicum, etc. On the basis of the floral composition, the geological age of the Yangshan Formation flora belonged to the late Early Carboniferous epoch, corresponding approximately to late Visean to early Namurian A. The present flora could be compared with contemporaneous floras from eastern Gansu, Shanyang of Shaanxi, South China and western Malaysia, which was closest to the Shanyang flora. In addition, the authors also discussed the distribution of late Early Carboniferous floras in other parts of the world.  相似文献   

12.
Ferns are diverse and abundant in the Lower Liassic flora of the Mecsek Mountains in south Hungary. The morphogenus Cladophlebis Brongniart, 1849, and the genus Todites Seward, 1900, show a high diversity. In the examined material, most of the characteristics used in taxonomy vary, showing transitional forms that cast doubt on the separation of species established on the grounds of either a low number of specimens, a low number of features or uncharacteristic differences.  相似文献   

13.
Use of the genus Sphenobaiera Florin for deeply divided ginkgoalean leaves lacking a petiole is discussed. The type material of the species Sphenobaiera ikorfatensis (Seward) Florin from the Lower Cretaceous at Ikorfat in West Greenland is diagnosed, redescribed and the lectotype designated. The cuticle, which is described and figured in detail for the first time, shows the leaf to be amphistomatic and allows previous identifications of Sphenobaiera ikorfatensis in Lower Cretaceous floras from Siberia and China to be confirmed.  相似文献   

14.
A male cone associated with Brachyphyllum expansum (Sternberg) is described from the Middle Jurassic of the Elburz Mountains in Northern Iran (Persia). The cone is described as M. rishra a new species of Masculostrobus Seward and the genus is emended to restrict its use for conifer male cones containing non-saccate pollen. M. rishra is compared with the cones occurring with B. expansum at the type locality of the latter in England. M. rishra contains pollen of the kind known as Classopollis torosus (Ressinger) sensu lat. and it is compared with the male cones of the Jurassic conifers, Cheirolepidium muensteri (Schenk), Brachyphyllum Scotti Kendall and Pagiophyllum connivens Kendall. The possibility that these conifers with similar male cones and pollen all belong to a single family, the Cheirolepidaceae, is suggested.  相似文献   

15.
《Nordic Journal of Botany》2007,25(3-4):227-237
The orchid flora of the Iberian Peninsula is relatively well known, but its biogeographical and diversity patterns have until now remained unanalysed. This work compares the richness of this flora with that of 27 other territories in different continents and at different latitudes, with the aim of establishing whether it is richer or poorer than might be expected. Latitude was found to be an excellent predictor of regional orchid species richness. With 122 taxa, the orchid flora of the Iberian Peninsula is more or less as diverse as that of other Mediterranean areas of similar latitude (e.g. France, Greece or Italy), but more diverse than other European or indeed North African orchid floras. In this study, the Iberian orchid species were assigned to eight monophyletic clades and the global distribution of these are mapped to establish continental affinities between the floras. A recent floristic account on the Iberian orchids was also used to assign the orchid taxa to habitats, and the relationship between the number of endemisms and their habitats was analysed. The patterns of endemism differed in different habitats. Very high levels of endemism were found in habitats peculiar to the Mediterranean Basin, indicating the relict status of its orchid flora.  相似文献   

16.
A low-diversity Early Jurassic flora preserved in floodbasin siltstones of the Marburg Subgroup at Inverleigh Quarry in the Clarence-Moreton Basin, eastern Australia, is dominated by Allocladus helgei Jansson sp. nov., a conifer with denticulate leaves tentatively attributed to Araucariaceae. The assemblage also includes Rintoulia variabilis and Caytoniales, (Caytonia cucullata McLoughlin sp. nov. and cf. Sagenopteris nilssoniana), reinforcing the wide distribution of this order in Early to Middle Jurassic floras of Gondwana. Ferns (Cladophlebis and Sphenopteris species) and isoetalean lycophytes (Isoetites sp.) constitute the herbaceous elements of the flora. The palynoflora is dominated by cheirolepidiacean (Classopollis) pollen and is attributable to the upper part of the Corollina (= Classopollis) torosa Zone of late Pliensbachian–early Toarcian age (180–185 Ma). The Inverleigh flora represents one of the few Australian assemblages dated between the major phases of floristic turnover at the end of the Triassic and the Toarcian. Sedimentological characteristics, cuticular features of the conifer leaves and the abundance of free-sporing plants indicate a relatively humid palaeoclimate for the Clarence-Moreton Basin Early Jurassic.  相似文献   

17.
Middle Eocene age caesalpinioid and mimosoid legume leaves are reported from the Mahenge site in north-central Tanzania. The Mahenge flora complements a sparse Paleogene tropical African fossil plant record, which until now consisted of a single macrobotanical assemblage, limited palynological studies in West Africa and Egypt, and fossil wood studies primarily from poorly dated deposits. Mahenge leaf macrofossils have the potential to add significantly to what is known of the evolutionary history of extant African plant groups and to expand our currently limited knowledge of African Paleogene environments. The site is associated with a kimberlite eruption and demonstrates the potential value of kimberlite-associated lake deposits as much-needed resources for African Paleogene floras. In this report we document a relatively diverse component of the flora consisting of the leaves of at least five species of Leguminosae. A new species of the extant genus Acacia (Mimosoideae), described herein, is represented by a bipinnate leaf. Another taxon is described as a new species of the extant genus Aphanocalyx (Caesalpinioideae), and a third leaf type may be related to the extant genus Cynometra (Caesalpinioideae). Two additional leaf types are less well understood: one appears to be referable to the Caesalpinioideae and subfamily affinities of the other taxon are unknown.  相似文献   

18.
黑龙江省东部鸡西盆地早白垩世穆棱组植物化石新材料   总被引:4,自引:0,他引:4  
杨小菊 《古生物学报》2003,42(4):561-584
系统描述了最近采集的穆棱组植物化石22属23种,其中的两种被子植物叶化石均为具原始被子植物叶特征的小型叶,在该植物群中尚属首次发现。运用扫描电镜(SEM)等方法对其中的Tyrmia sp.,Nilssoniopteris sp.,Ginkgoites cf..sibirica,.Sphenobaiern sp.,Elatocladus manchurica等化石的叶角质层进行了研究。据已有的资料统计,穆棱组迄今已知有化石植物31属38种。该植物群以真蕨类占据绝对优势,裸子植物也相当丰富,其中的大多数种类主要见于早白垩世,穆棱组的地质时代应属早白垩世巴列姆期或巴列姆-阿普梯早期。植物组合中以丰富的热带及亚热带型植物为主要特点,未发现针叶类型的植物,说明早白垩世穆棱组沉积时,该地区的气候温暖湿润;另一方面,落叶的银杏类和松柏类,以及裸子植物木化石中具有清楚的生长轮,又说明该地区的古气候存在着季节变化。该植物群属于早白垩世西伯利亚植物区或加拿大-西伯利亚植物区。  相似文献   

19.
刘艳  李录 《植物学通报》2006,23(4):380-388
选取属级分类单元作为统计变量,Dice系数作为统计公式,对中国早中侏罗世较具代表性的18个植物群进行了相似性的聚类分析.研究结果显示出的区系划分格局在一定程度上支持了前人对植物群时代和性质的判断,同时提出香溪组、万宝组所含植物群的特殊组合与时空因素值得深入研究;中国北方早侏罗世植物群、北方中侏罗世植物群以及南方早中侏罗世植物群三者之间的差异、联系及范围界限需要进一步深入研究.本研究是对古植物学区系研究的有益探索,为中国侏罗纪植物群的大区域系统研究提供了数据基础和参考依据.  相似文献   

20.
刘艳  李录 《植物学报》2006,23(4):380-388
选取属级分类单元作为统计变量, Dice系数作为统计公式, 对中国早中侏罗世较具代表性的18个植物群进行了相似性的聚类分析。研究结果显示出的区系划分格局在一定程度上支持了前人对植物群时代和性质的判断, 同时提出香溪组、万宝组所含植物群的特殊组合与时空因素值得深入研究; 中国北方早侏罗世植物群、北方中侏罗世植物群以及南方早中侏罗世植物群三者之间的差异、联系及范围界限 需要进一步深入研究。本研究是对古植物学区系研究的有益探索, 为中国侏罗纪植物群的大区域系统研究提供了数据基础和参考依据。  相似文献   

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