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1.
A sphenopsid from the Upper Devonian (Famennian) Xiejingsi Formation, south-western Hubei Province, China, previously named as various species in Sphenophyllum , Hamatophyton , Bowmanites and Sphenophyllostachys , is now reinvestigated and assigned to a new taxon, Rotafolia songziensis gen. et comb. nov. Its ribbed axes are anisotomous and possess slightly expanded nodes. Lateral axes are inserted at nodes on main axes. Whorls of much divided vegetative leaves are attached at nearly right angles to nodes of basal axes, and at acute angles to nodes of terminal axes. There are six leaves per whorl. The terminal strobilus includes a central axis and verticils of fertile units. Each fertile unit consists of a bract and numerous sporangia. The margin of the elongate-cuneate bract bears a distal and many lateral elongate segments. Clusters of elongate sporangia are abaxially attached to the base of the bract at the same level. The axis has an actinostele, composed of a three-ribbed, exarch primary xylem and radial secondary xylem. Although Rotafolia songziensis closely resembles Hamatophyton verticillatum in axis character, leaf morphology and primary xylem type, they are quite different in strobilar structure. Taxonomically, Rotafolia is placed in the order Sphenophyllales by three well-defined characters: 1) whorled appendages; 2) ribbed protosteles; 3) exarch primary xylem maturation.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 21–37.  相似文献   

2.
具叶舌痕的圆印木状茎干在安徽巢湖上泥盆统的首次发现   总被引:2,自引:2,他引:2  
在描述的几块产自安徽巢湖五通组中上部(法门期)的圆印木状茎干中,首次发现其中一块标本具有明显的叶舌痕,它与另一块叶痕特征相同但不具叶舌痕的标本共生.说明它们很可能应归为同一种植物。因此叶舌痕的有无很可能与化石的保存状态有关。圆印木属与窝木属仅根据茎干叶痕特征是难于区分的。但由于这两个属的生殖部分(球果)存在差别,目前仍被视为不同的属。当前的标本未发现生殖部分,难于确定其归属。笔者建议,为了实用方便将这类发现于上泥盆统的标本,暂归为Bothrodendron(Cyclostigma)属名之下,作为形态属或卫星属来处理。  相似文献   

3.
Recently collected specimens of Danaeites rigida Gu and Zhi from the Upper Permian of south China have been subjected to detailed morphological investigations in order to reveal features of their fertile pinnules. The specimens are preserved as compression/impressions and possess pecopteroid-type pinnules with a single row of synangia on either side of the pinnule midvien. Individual synangia are bilaterally symmetrical, sessile, and their bases are embedded in the tissues of the pinnules. Synangia possess 18–24 sporangia that are laterally fused to one another throughout their entire length. Sporangial dehiscence is through a longitudinal slit and sporangia contain trilete spores with a granular ornamentation, referable to the dispersed spore Cyclogranisporites. This combination of characters is unique in specimens preserved by compression/impression although they are similar to those known in permineralized marattialean fertile fronds. However, anatomical details salient to the identification of these permineralized taxa are not identifiable in impression/compression fossils such as Danaeites. The taxonomic and phylogenetic implications of these findings are considered in detail and we conclude that Danaeites has closer links with Marattia than with Danaea.  相似文献   

4.
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   

5.
本文描述和讨论广东连阳地区谷田组地层的化石共14属18种,即:Paracalamites sp.,Annularia pingloensis(Sze)Gu er Zhi、Lobatannularia cathaysiana Yao、L.multifoliaKon'on et Asama、L.sp.、Schizonerua wangtangiana sp.nov.、Pecopteris hemitelioidesBrongn.、P.valida sp.nov.、Cladophlebis varia sp.nov.、Danaeites guangdongensis sp.nov.、Ptychocarpus unauriculatus sp.nov.、Odontopteris plicatoides sp.nov.、Neuropteri-diopsis longovata gen.et sp.nov.、Compsopteris contracta Gu et Zhi、Gigantonoclea cra-ssa sp.nov.、Gigantopterts?nicotianaefolia Schenk、G.parvipinnulata sp.nov.和 Rhipido-psis sp.等,其中有1新属、9新种和2未定种。谷田组顶部发现了早二叠世晚期的(竹蜓)类层,下段则与下伏的茅口组假整合。植物群的地质时代为早二叠世晚期。  相似文献   

6.
This paper deals with the fossil plants from Gutian Formation in Lianyang, Guangdong, totaling 14 genera and 18 species. They are: Paracalamites sp., Annularia pinglogensis (Sze) Gu et Zhi, Lobatannularia cathaysiana Yao, L. Multifolia Kon’on et Asama, L. sp., Schizoneura wangtangiana sp. nov., Pecopteris hemitelioides Brongn., P. valida sp. nov., Cladophlebis vavia sp. nov., Danaeites guangdongensis sp. nov., Ptychocarpus unauriculatus sp. nov., Odontopteris plicatoides sp. nov., Neuropteridiopsis longovata gen. et sp. nov., Compsopteris contracta Gu et Zhi, Gigantonoclea crassa sp. nov., Gigantopteris ?nicotianaefolia Schenk, G. parvipinnulata sp. nov. and Rhipidopsis sp. Among them one new genus, 9 new spp. and 2 undetermined spp. are described. According to the fusulinids lived in the late Early Permian era are descovered at the top of this Formation, the geological era of present flora must not be later than late Early Permian. Therefore, the geological era of Gutian Formation are certain to be the Late Early Permian.  相似文献   

7.
This paper describes a new microstrobilus of palaeozoic Cycadaceae collected from the upper part of Lower Shihezi Formation, Dongshan Mine, Taiyuan, Shanxi, China and named it as Cycadostrobilus paleozoicus Zhu, gen. et sp. nov. This new cycad is the oldest microstrobilus to our knowlege of cycads. In the same locality and layer, there are Primocycas chinensis Zhu et Du, Sphenophyllum emarginatum Brongn. , S. costae Sterz. , S. verticallatum (Schloth.) Brongn. , S. oblongifolium (Germ. et Kaulf. ) Ung. , Tingia carbonica (Schenk.) Halle, T. hamaguchii Kon’no, Macrostachys huttoniformis Halle, Sphenopteris norinii Halle, S. firmata Sze, S. gothanii Halle, Sphenopteridium pseudogermanicum (Halle) Gu et Zhi, Pecopteris feminaeformis (Schloth.) Sterz. , P. wongii Halle, P. tuberculata Halle, P. unita Brongn. , P. taiyuanensis Halle, Emplectopteris triangularis Halle, Taeniopteris norinii Halle, T. spp. , Cordaites principalis (Germ.) Gein. , Cornucarpus patulus Halle, Radicites spp. and a few taxa unknown to palaeobotanical data. The authors consider that Cycadostrobilus paleozoicus is the same species as Primocycas chinensis, and its veg.etative leaves are similar to those of the genus Taeniopteris, e.g.T. norinii Halle.  相似文献   

8.
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   

9.
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   

10.
This paper describes three new species of Pisidiidae, Pisidium (P.) zhushutangense, Sphaerium(S.) pyrum and Sphaerium (S.) fujianense, assoeiated with very abundant Plicatounio (P.) naktongensis Kobayashi et Suzuki, Plicatounio (P.) fujianensis Gu et Ma and Trigonioides (T.) quadratus Gu et Ma from the Lower Cretaceous upper Hekou Formation of Zhushutang, Hekou Basin, Ninghhua, Fujian. In Japan, the last two species, Sphaerium (S.) pyrum and Sphaerium (S.) fujianense, or their affinis coexist with each other in the upper Wakino Subgroup, the lower Wakamiya and upper Wakamiya Formations, and the lower Inakura Formation, Yamaji Shale, which very probably can be correlated with the upper Hekou Formation yielding these two species.The distinction between Pisidium and Sphaerium is summarized in Table I.  相似文献   

11.
胡雨帆 《植物研究》1986,6(3):147-153
近年来,笔者在系统研究了新疆准噶尔盆地南缘的古生代植物化石后,发现了两种早已绝灭了的科达(Cordaites)的生殖器官化石,一种是长苞科达穗(Cordaianthus volkmannii(Ett.)Zeiller),另一种是短苞科达穗(比较种)(Cordaianthus of.curtus Sze);同时还发现了一种最古老的松柏类化石——双羽杉(比较种)(Walchia of.bipinata Gu et Zhi)这些化石产生在准噶尔盆地南缘的乌鲁木齐市东南的下芨芨槽子群中,其地质时代隶属於早二叠晚期(P12)。  相似文献   

12.
Emplectopteridium alatum Kawasaki 的脉序*   总被引:2,自引:2,他引:0  
Emplectopteridium alatum Kaw. 的脉序历来被描述为叶脉结网并具邻脉,主要基于具有邻脉这一特征,该种被归于美羊齿类.经笔者研究,这种植物没有邻脉而具伴网眼.这样,不但 E. alatum Kaw. 的分类位置需重新考虑,而且所谓 Emplectopteridium 演化系的基础也就完全瓦解.  相似文献   

13.
This paper deals with the characteristics and occurring state of the sporangia of Protolepidodendron and its significance. The authors discovered that the sporangia with a short sporangiophore spread out from the axis of the fertile branch. There is a distance from the base of sporophyllary leaves to the setting point of the sporangiophore. Some sporangia divideinto suspended and symmetrical sporangia at the tip of the sporangiophore. But the most of sporangia do not divide. According to the characteristics of the sporangia of Protolepidodendron Krejci, which can be distinguished from genera Barrandeina (Krejci) Stur and Longos-tachys Zhu, Hu et Feng. Protolepidodendron lixianense sp. nov. is also described in this paper.  相似文献   

14.
The morphology of the fertile pinnules of Fascipteris densata Gu et Zhi have been subjected to a detailed morphological investigation based on recently collected specimens from the Upper Permian of Yunnan Province, south China. These investigations have revealed that this species possesses synangia of the Asterotheca-type, situated in two or three rows either side of the midrib on a Fascipteris-type pinnule. This arrangement of Asterotheca-type synangia is extremely unusual considering that all other reports of this genus are with a single row of synangia located on each side of the midrib of a pecopteroid-type pinnule. As a consequence of this unique morphological arrangement, a new genus, Zhutheca densata Liu, Li et Hilton gen. et comb. nov. has been created to distinguish this material from other specimens of the Asterotheca and Fascipteris types. The structure and arrangement of the fertile pinnule of Zhutheca are compared with other Palaeozoic and Mesozoic marattialean taxa with which it shares certain features of its morphology. In addition, the stratigraphic, evolutionary and phylogenetic significance of Zhutheca are considered in detail.  相似文献   

15.
Vallitheca valentia gen. et sp. nov. is a permineralized, synangiate fructification of probable seed fern affinities from the Wewoka Formation (Desmoinesian) near Ada, Oklahoma. Synangia are oblong to pyriform, average 1 cm long, and contain 32 to 48 tubular sporangia embedded proximally in ground tissue. The sporangia are arranged within the synangia in a unique pattern: a ring of peripheral sporangia dehisces toward the center of the synangium and a central group of sporangia dehisces outward. This unique arrangement is unlike that of any currently recognized group.  相似文献   

16.
吐鲁番-哈密盆地早二叠世晚期植物群   总被引:2,自引:1,他引:2  
首次记述了吐鲁番-哈密盆地的早二叠世晚期植物11属13种(包括4新种和4未定种),这是一个以科达类及其相关属为主的安加拉植物群。典型的安加拉植物Vojnovskya属的发现,不但在时代的判定上,而且在植物地理区划上都具重要意义。文中还对这一植物群的特征和时代问题作了简要讨论。  相似文献   

17.
近年来对我国9个省的悬钩子属植物资源进行了调查采集,并在南京中山植物园建立了田间种质库进行观察研究。本文报导在云南省悬钩子资源调查中发现的1个新种和5个新变种,它们是:Rubus godongensis Gu et Li, R. biflorus Buch.-Ham.ex Smith var.spinocalycinus Gu et Li, R. glabricarpus Cheng var.eglandulosus Gu et Li, R. gongshanensis Yü et Lu var.eglandulosus Gu et Li, R. parvifolius L.var.purpureus Gu et Li, R. viburnifolius Focke var.apetalus Gu etLi.  相似文献   

18.
Yang H  Henning D  Valdez BC 《The FEBS journal》2005,272(15):3788-3802
RNA helicase II/Gu(alpha) is a multifunctional nucleolar protein involved in ribosomal RNA processing in Xenopus laevis oocytes and mammalian cells. Downregulation of Gu(alpha) using small interfering RNA (siRNA) in HeLa cells resulted in 80% inhibition of both 18S and 28S rRNA production. The mechanisms underlying this effect remain unclear. Here we show that in mammalian cells, Gu(alpha) physically interacts with ribosomal protein L4 (RPL4), a component of 60S ribosome large subunit. The ATPase activity of Gu(alpha) is important for this interaction and is also necessary for the function of Gu(alpha) in the production of both 18S and 28S rRNAs. Knocking down RPL4 expression using siRNA in mouse LAP3 cells inhibits the production of 47/45S, 32S, 28S, and 18S rRNAs. This inhibition is reversed by exogenous expression of wild-type human RPL4 protein but not the mutant form lacking Gu(alpha)-interacting motif. These observations have suggested that the function of Gu(alpha) in rRNA processing is at least partially dependent on its ability to interact with RPL4.  相似文献   

19.
Permian specimens of Sphenophyllum with preserved cuticular anatomy have been discovered in Cathaysia and have prompted a detailed re-evaluation of the genus in the Gigantopteris flora in South China. New specimens are described and previously published material is re-examined to clarify taxonomic diversity and to establish geographic and stratigraphic ranges for each species. Recognized taxa include Sphenophyllum apiciserratum sp. nov., S. koboense Kobatake, S. meridionale sp. nov., S. minor (Sterzel) Gu and Zhi, S. sinocoreanum Yabe, S. cf. sinocoreanum Yabe, and S. aff. speciosum (Royle) McClelland. Cuticles of Sphenophyllum apiciserratum and S. koboense are hypostomatic with randomly disposed ordinary cells in intercostal regions. Specific concepts are clarified and unresolved taxonomic problems are discussed. The South China taxa are compared with those from Euramerican, Gondwanan and Angaran floras, and the South China Cathaysian species are found to be taxonomically distinct.  相似文献   

20.
烟叶大羽羊齿Gigantopteris nicotianae f olia Schenk是地质和古生物工作者熟知的植物化石。由于Halle(1927)曾将单网羊齿的种误归并于这一种内,致使它一度成为广见于华夏古植物区二叠纪陆相地层的植物化石。后来的研究表明(Guand Zhi,1974;姚兆奇,1983;Glasspool et al.,2004),除了河南平顶山的可疑标本外(Sze,1954),此种可作为华南冷坞期的标志性植物。最新资料证实(杨关秀等,2006),产自河南禹州和临汝上石盒子组(云盖山组)的标本完全显示了G.nicotianaefolia的特征,说明了这个种在华北的存在,从而扩大了这种植物的分布区。根据烟叶大羽羊齿的时空分布规律,文章认为河南的上石盒子组完全可与江苏龙潭组和江西乐平组老山段下亚段的含煤层位对比,时代应属瓜德鲁普世冷坞期(Capitanian)。文中较详细阐述将河南上石盒子组的时代定为冷坞期而不是晚二叠世早期(吴家坪期)的观点,并引证磁性地层方面证据,支持这一结论。  相似文献   

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