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1.
前言Desmiophyllum一名系Lesquereux(1878)根据美国石炭纪一种与狭型科达树(Poacordaites)相类似的叶部化石创立的,模式种D. gracile的叶是单个或成组地接触在一保存不完全的轴上,被认为是一个不清楚的种,可能与Cordaites同物异名,因而Desmiophyllum长期未被采用,后来Solm-Laubach将这个属名的含义加以厘定,用于代表中生代叶枝形态不明、单独保存的狭形叶但不能归入已知属的叶部化石。此后,这个属名方被古植物学者广泛采用。从国内外定为Desmiophyllum的各个种的叶角质层构造来看,内容复杂,特征各异,包括  相似文献   

2.
张汝玫 《古生物学报》1991,30(1):125-125
前言Desmiophyllum一名系Lesquereux(1878)根据美国石炭纪一种与狭型科达树(Poacordaites)相类似的叶部化石创立的,模式种D. gracile的叶是单个或成组地接触在一保存不完全的轴上,被认为是一个不清楚的种,可能与Cordaites同物异名,因而Desmiophyllum长期未被采用,后来Solm-Laubach将这个属名的含义加以厘定,用于代表中生代叶枝形态不明、单独保存的狭形叶但不能归入已知属的叶部化石。此后,这个属名方被古植物学者广泛采用。从国内外定为Desmiophyllum的各个种的叶角质层构造来看,内容复杂,特征各异。  相似文献   

3.
中国二叠纪苏铁科新属、种——古生铁花   总被引:2,自引:0,他引:2  
本文是继中国始苏铁Primocycas chinensis Zhu et Du之后,又报道一种古植物文献未见记载的早二叠世晚期苏铁科小孢子叶球,命名为古生铁花(新属、种)Cycadostrobilus paleozoicus Zhu,gen. et.sp.nov.标本采自我国山西省太原市东山煤矿的下石盒子组,它是世界迄今已知的一种最古老的小孢子叶球化石。和本新属同层发现的化石,除了中国始苏铁之外,还有楔叶Sphenophyllum、齿叶Tingia,楔羊齿Sphenopteris、楔叶羊齿Sphenopteridium、织羊齿Emplectopteris、栉羊齿Pecopteris、大芦孢穗Macrostachya、科达Cordaites、带羊齿Taeniopteris、角籽Cornucarpus和几种也未见记载而形态又非常特殊的植物。本文认为当前报道的古生铁花(新属、种)很可能和中国始苏铁同属一种植物,其营养叶可能是疏脉带羊齿Taeniopteris norinii Halle。  相似文献   

4.
江苏徐州煤田太原组20号煤层中一种分散角质层,根据其表皮构造特征及其它证据,认为是科达叶的角质层。利用光学显微镜和扫描电镜对这种角质层进行了详细研究,并与国内外研究较详细的几种科达叶的表皮构造进行了比较,表明当前标本是一种新和产达叶表皮构造类型。  相似文献   

5.
为了更好地了解晚古生代楔叶属的物种多样性及形态演化,通过对化石宏观形态的研究以及与相似化石种的对比,确定甘肃永昌太原组中几种楔叶植物化石的分类位置。本文共鉴定楔叶植物化石2属5种,其中包括营养叶和繁殖器官。基于这些楔叶属的新材料,对椭圆楔叶以及马齿楔叶的茎轴表面纵纹、叶片分裂次数等特征进行修订。同时报道楔叶穗属一新种Bowmanites yongchangensis sp. nov.。结合该属在晚古生代的古地理分布情况,表明在乌拉尔世早期该研究区内楔叶属植物呈现出较高的物种多样性,并推测该属植物的起源时间不晚于晚泥盆世法门期,在维宪期由华南地区传入华北地区后,于宾夕法尼亚亚纪晚期传入龙首山地区所在的阿拉善地块。  相似文献   

6.
化石采自云南腾冲上新统芒棒组.通过对比叶结构和角质层微细构造特征,从宏观和微观两个角度将化石鉴定为樟科植物樟(相似种)Cinnamomum cf.camphora(L.)Presl.化石叶片为卵状椭圆形,基部宽楔形,全缘,离基三出脉;上表皮无气孔器,表皮细胞为不规则四边形或多边形;下表皮细胞为不规则多边形,脉络上可见少...  相似文献   

7.
中国华夏植物区二叠纪几种科达植物分散角质层及其意义   总被引:2,自引:0,他引:2  
中国华夏植物区科达植物的研究历史虽然最早可上溯至1883年,但直到1991年才首次报道其角质层构造。到目前为止,中国华夏植物区总共描述了4种科达植物原位角质层和3种分散角质层。但与欧美植物区相比,有关中国华夏植物区科达植物角质层的研究工作还较薄弱。本文较详细地描述了3种产自中国华夏植物区二叠纪煤系地层中的科达植物分散角质层。其中2种采自华北亚区南缘的安徽淮南新庄孜矿山西组A1煤顶板,地质时代为早二叠世;另一种采自华南亚区的贵州水城矿区大河边矿龙潭组顶部的11号煤层,地质时代为晚二叠世早期。将这3种科达植物分散角质层与已知的欧美植物区和中国华夏植物区的种类进行了对比,认为它们都是新的类型。讨论了这3种新的科达植物分散角质层所具有的古植物学意义。  相似文献   

8.
中国华夏植物区科达植物的研究历史虽然最早可上溯至1883年,但直到1991年才首次报道其角质层构造.到目前为止,中国华夏植物区总共描述了4种科达植物原位角质层和3种分散角质层.但与欧美植物区相比,有关中国华夏植物区科达植物角质层的研究工作还较薄弱.本文较详细地描述了3种产自中国华夏植物区二叠纪煤系地层中的科达植物分散角质层.其中2种采自华北亚区南缘的安徽淮南新庄孜矿山西组A1煤顶板,地质时代为早二叠世;另一种采自华南亚区的贵州水城矿区大河边矿龙潭组顶部的11号煤层,地质时代为晚二叠世早期.将这3种科达植物分散角质层与已知的欧美植物区和中国华夏植物区的种类进行了对比,认为它们都是新的类型.讨论了这3种新的科达植物分散角质层所具有的古植物学意义.  相似文献   

9.
对内蒙古准葛尔旗二叠纪山西组的一种科达叶的角质层,进行了光学显微镜和扫描电镜观察。比较国内外研究较详细的几种科达叶表皮构造,表明当前标本为科达属一新种,命名为内蒙科达(Cordaitesneimengensissp.nov)。  相似文献   

10.
一、前言早已绝灭的裸子植物——科达树(Cordaites)曾繁盛于石炭—二叠纪植物界。由于化石保存条件等限制,古植物学家们以往多以器官属名或限于部分器官的解剖属名作为科达树各组成部分的分类。在众多的古植物文献中,常见的属名主要有: 叶部化石:Cordaites Unger, 1850, Eu-cordaites Grand'Eury, 1877, Dory-cordaites Grand'Eury, 1877, Poa-cordaites Grand'Eury, 1877, Scuto-cordaites Renault et Zeiller, 1885, Dictyo-cordaites Dawson, 1890, Noeggerathiopsis Feistmantal, 1879, Cordaites(Co-  相似文献   

11.
广西百色盆地更新世樟科两种植物角质层研究   总被引:3,自引:0,他引:3  
本文描述的具角质层的两块叶化石,产自广西百色盆地更新统长蛇岭组。经与现代植物的角质层对比研究后,确定这两块叶化石分属于樟科的两属两种,即油丹(近似种)(Alseoda-phne cf.hainanensis Merr.)和紫楠(近似种)[Phoebe cf.sheareri(Hemsl.)Gamble]。研究结果表明,角质层在鉴定被子植物化石中具有可靠的价值。  相似文献   

12.
Two fossil leaves with cuticle described here were collected from the Pleistocene Changseling Formation of Baise Basin, Guangxi. A detailed comparison of the cuticular analysis between the fossils and their living equivalents indicated that the two fossil species belong to 2 genera of Lauraceae, that is, Alseodaphne of, hainanensis Merr. and Pheobe cf. sheareri (Hemsl.) Gamble. The first report on lauraceous fossil leaves with cuticle in China showed that cuticular analysis had a reliable value in identifying the angiospermous fossil plants.  相似文献   

13.
重点描述云南腾冲晚第三纪两种被子植物化石Betula mioluminifera Hu et Chaney,Carpinus subcordata Nathorst的角质层构造,并分析它们的现存最近亲缘种B.luminifera Winkler和C.cordata B1.var.mollis Cheng et Chen的表皮特征。实验分析证明:化石叶片的气孔参数可以推测地质历史时期大气CO2的浓度,并进而分析古环境的变化。C.subcordata Nathorst叶片能作为大气CO2浓度的生物指标。  相似文献   

14.
长翅目昆虫在地史纪录上可以追溯到早二叠纪,是全变态昆虫中最原始的种类之一.截至目前,29篇关于中国长翅目昆虫化石分类的论著发表,共描述我国长翅目昆虫化石11科28属51种,这些化石分布于从三叠纪到白垩纪的不同地层中.本文通过图表提供了我国已发现的长翅目化石名录并介绍了其分布和年代,回顾了我国长翅目昆虫化石的研究进展,指出了一些分类存在的问题,简要慨述了长翅目中一些科的起源与演化以及长翅目与其它全变态昆虫的关系.我国长翅目化石种类丰富,但在基础分类、系统演化方面还缺乏系统的研究,因而许多工作甚至最基础的分类工作亟待开展.  相似文献   

15.
浙江长兴煤山二叠纪末大灭绝化石记录的置信区间分析   总被引:5,自引:2,他引:3  
王Yue  曹长群 《古生物学报》2001,40(2):244-251
化石的保存与采集普遍具有随机性,以至直接观察结果往往不能反映真实的生物分类单元延限以及生物事件,而必须对化石记录进行统计分析,从定量的角度发掘其可信内涵,。浙江长兴煤山财区二叠系-三叠系剖面的化石资料经过数十年采集研究,已提出多期生物群灭绝模式,文中运用置信区间作了分析,。说明了长兴期末生物大灭绝为突发性,灾难性事件。  相似文献   

16.
Fossil remains of beetles are described from two Lower Triassic localities: Entala (Induan) and Tikhvinskoe (Olenekian). Only one beetle fossil was previously known from the Lower Triassic of Tikhvinskoe. The fossils are rather few and poorly preserved, but they are worth describing as finds rare for the Lower Triassic. Five fossils from Entala most probably belong to beetles of the same species of the formal genus Pseudochrysomelites. Beetles of this genus are especially abundant in deposits close to the Permian–Triassic boundary and can be considered “disaster taxa.” There are no known cases, either in the Permian or in the Middle–Upper Triassic, of a random sample of five specimens belonging to a single species. This suggests that in the Entala oryctocenosis the species diversity of beetles is extremely low. All three beetle fossils found in Tikhvinskoe belong to beetles of different species, showing that diversity had already started to increase. However, it remained low, and all fossils belong to the formal family Schizocoleidae, and two of the three belong to the same genus, Pseudochrysomelites. The Khei-Yaga locality, which immediately follows Tikhvinskoe in time (topmost Olenekian or early Anisian), already contains beetles of the families Asiocoleidae and Permosynidae. In the Lower Anisian of the Buntsandstein, such typical Mesozoic beetles as Cupedidae and Coptoclavidae have been recorded. The appearance of such advanced beetles as early as the Lower Anisian suggests that the famous Permian–Triassic crisis was not as deep as it is usually believed, and many beetles survived it, disappearing, however, from the fossil record in the Early Triassic.  相似文献   

17.
滇西晚石炭世一早二叠世苔藓虫   总被引:2,自引:0,他引:2  
简述了4个双壳类化石组合特征及沉积环境,描述了双壳类2新属(Sichuatrigonia, Pseudoburmesia)和11新种(包括新亚种).  相似文献   

18.
The phylogenetic placements of leaf fossils of Nothofagus (Nothofagaceae) were determined using parsimony analyses of molecular and morphological data for extant species combined with morphological data for fossils. Placement was possible for only seven of the 30 or so described fossil species of Nothofagus because only these had sufficiently good preservation of both cuticular and leaf architectural characters. In combined analyses of morphology and molecular data, leaf cuticular characters showed little homoplasy. In contrast, many architectural characters, including some leaf margin and venation characters, showed high homoplasy, making it difficult or impossible to accurately determine the phylogenetic affinities of impression fossils of this genus.  相似文献   

19.
Large leaves, new to the fossil record, from the Claiborne Formation in western Tennessee have been collected and analyzed. Careful analyses of venation and cuticular anatomy indicate that these fossil leaves contain specific characters found in modern species of the genus Philodendron subgenus Meconostigma. Features of venation were taxonomically more useful than other features. Reports of fossils of the Araceae are scarce and those few fossils assigned to the family frequently have been inadequately studied. This report establishes a reliable and carefully documented occurrence of the Araceae in the fossil record, and provides information concerning the differentiation of the family in time and the distributions of the genus Philodendron.  相似文献   

20.
The genus Calocedrus Kurz is characterized by flattened branches covered with decussate and dimorphic leaves. In this study, we describe fossil foliage of Calocedrus discovered in the Shangcun Formation (early Oligocene) of the Maoming Basin, South China. The fossils have wedge‐shaped branchlet segments and scale‐like strongly dimorphic leaves, similar to the fossil species Calocedrus lantenoisi (Laurent) Tao. There have been no detailed studies of the morphological features and cuticle structures of C. lantenoisi. Therefore, a newly emended diagnosis of the species C. lantenoisi is given based on a detailed study of leaf morphology and cuticular characters exhibited by the Maoming fossils. This is one of the earliest fossil records of Calocedrus in the world, providing additional evidence for the early biogeographic history of this genus and supporting the inference that eastern Asian Calocedrus is primitive among all the living species. The extant species of Calocedrus are mainly distributed in mountainous regions. On the basis of the “nearest living relative” analysis, we propose that the Maoming Basin was adjacent to a mountainous region during the early Oligocene.  相似文献   

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