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1.
Pale0nt0IogicStudiesSubclassGaleaspidaHalsteadTarl0,l9670rderHuanana8piformesJanvier,l975FamilyGantar0stra8pidaeWangetWang,l992GenusCantarostraspisWangetWang,l992CQntarostra8pisgeniWangetWang,l992(Fig.l3Pl-II,4-5)1992,Gantarostraspisgeni,Wang,J.Q.etWang,N.Z.,Fig-l,Pl.l.HolotypeAdorsalshieldV9758,LowerDevonianPosongchongF0rmation,Gu-mu,Wenshandistrict,Yunnan-ReferredspeeimensAdorsalshieldVlO494.1;arostra1pr0cessV1O494.2.Loca1ityandh0riz0nXujiach0ng,Xishan,Qujing,Yunnan,Lowe…  相似文献   

2.
从鱼化石的角度对滇东泥盆系下述含鱼地层进行了分析,并认为:1)曲靖地区下泥盆统徐家冲组与坡松冲组或四川的平驿铺组、广西的那高岭组层位相当,时代为布拉格期;其层位低于含 duyunolepids-Kueichowlepis鱼类组合的贵州乌当组或舒家坪组,后者时代为埃姆斯期。2)滇东中泥盆统含两个不同时期的含鱼层,其中含Yinosteus-Wudinolepis鱼类组合的武定地区旧城组属中泥盆统早期,该鱼类组合现仅知分布于武定地区。而中泥盆统晚期含鱼地层,在曲靖地区由下而上包括穿洞组、上双河组和海口组三个岩石组;其中穿洞组+上双河组与武定的鱼子甸组对比,而海口组与曲靖组为同时异相;武定茶花箐组与曲靖组对比。3)文中时上述地层中的某些鱼化石的层位或鉴定作了评述或厘定。  相似文献   

3.
Abstract: The Lower Devonian Xujiachong Formation from the vicinity of Qujing City, Yunnan, China is interpreted as a terrestrial‐fluviatile‐lacustrine sequence. It contains important nonmarine biotas including plants, fish and invertebrates. The plants are particularly interesting as they include many endemic taxa. Dispersed spore assemblages have been recovered from the upper part of this formation. The spores are well preserved and of moderate thermal maturity. They are systematically described and four new species erected: Aneurospora xujiachongensis sp. nov., Chelinospora ouyangii sp. nov., Camptozonotriletes? luii sp. nov. and Leiozonospora xichongensis sp. nov. One new combination is proposed: Aneurospora conica (Ouyang and Lu) comb. nov. This is a rare report of a Lower Devonian dispersed spore assemblage from the South China Plate. Indeed, few dispersed spore assemblages of this age are known outside of Euramerica and Northern Gondwana. It is suggested that the Xujiachong Formation spore assemblages can all be equated to the polygonalisemsiensis Spore Assemblages Biozone (PE SAB) of Richardson and McGregor (1986) indicating an early (but not earliest) Pragian to ?earliest Emsian age. However, caution is urged, because biostratigraphical interpretation is difficult owing to distinct differences between dispersed spore assemblages from South China and Euramerica/Northern Gondwana. This almost certainly reflects palaeophytogeographical variation and regional endemism among early land plant floras on widely separated land masses. Palynofacies analysis supports a nonmarine origin for the deposits of the Xujiachong Formation, with the very rare marine palynomorphs that were encountered interpreted as reworked.  相似文献   

4.
内蒙古巴特敖包地区早泥盆世牙形刺   总被引:2,自引:1,他引:1  
内蒙古达茂旗(达尔罕茂明安联合旗)巴特敖包地区以碳酸岩相古生代地层发育而引人注意。经多年研究,特别是李文国等(1985)的研究,使本区珊瑚、腕足类、层孔虫、鹦鹉螺等大化石的研究工作已有一定基础,并依据牙形刺首先确定了在阿鲁共剖面有泥盆纪地层的存在。但本区泥盆纪地层仍存在很多问题,必须通过对牙形刺的研究加以解决。在王成源研究员的精心安排和亲自指导下,作者等在巴特敖包地区的七个剖面进行了系统取样研究。经对158个样品(重667kg)的分析,在本区发现了大量的原定为志留纪的早泥盆世地层,包括西别河组命名剖面。分析结果同时证明,本区不存在志留系温洛克统的沉积。巴特敖包剖面断层发育,志留—泥盆纪地层交替出现,巴特敖包组应取消,原定的阿鲁共剖面层序颠倒。本区地层应厘订为志留系的西别河组(罗德洛统—普里道利统)和下泥盆统的阿鲁共组(Lochkovian阶),前者以包尔汉图剖面为标准剖面,后者应寻找更好的标准剖面。本文重点总结巴特敖包地区早泥盆世的牙形刺。本区共建立了4个牙形刺带,文中共描述了8牙形刺属,21种,其中包括4亚种、1新种(Belodellataeniocuspidatasp.nov.)和1未定种。  相似文献   

5.
A new species of early land vascular plants, Huia gracilis, is described from the Lower Devonian (Pragian-early Emsian) Xujiachong Formation, Qujing district, Yunnan Province, southwestern China. The plant possesses K- or H-type branching in the rhizome and a dichotomously branched erect system. An axillary tubercle is sometimes present at the branching position. Fertile axes terminate in loose spikes comprising terminal and lateral sporangia arranged helically. Sporangia with long stalks are ovate or elongate-ovate and reflex adaxially. The sporangium dehisces longitudinally in the radial plane of the fertile axis into two parts. The xylem is probably centrarch. Tracheids of G-type are characterised by annular secondary thickenings, between which is a sheet with irregular simple perforations. There may be some 'pores' in the enclosing wall of the perforation. H. gracilis differs from the type species H. recurvata mainly in the branching pattern, more slender morphology of the stem, sporangium and stalk. It is suggested that Huia may have originated from the primitive Cooksonia-like plants.  相似文献   

6.
云南文山早泥盆世盔甲鱼类的新发现   总被引:4,自引:2,他引:2  
描述了采自云南东南部文山地区下泥盆统坡松冲组下部的无颌类化石,建立了盔甲鱼类的一新属、新种──纸厂文山鱼(Wenshampis zhichangsis gen.et sp.nov.),同时修订了两个盔甲鱼类的旧属、旧种──长吻三歧鱼(Sanqiapis rostrata)及长角大窗鱼(Macrothyraspislongicornis)。迄今为止,长吻三歧鱼仅在四川江油雁门坝的平驿铺组中部发现并记述过,长角大窗鱼也仅有一件采自云南广南坡松冲组中的正型标本,而纸厂文山鱼为滇东南文山地区首次记述的多鳃鱼类新属种,它与滇东北昭通地区下泥盆统坡松冲组中的让氏昭通鱼(Zhao-tongasis janvieri)最为相似。此次这三个盔甲鱼类属种在滇东南文山地区的发现,为该区下泥盆统的横向对比提供了重要的古鱼类学方面的证据。  相似文献   

7.
A new vascular plant, Hsüa deflexa sp. nov., is documented from the Lower Devonian ((upper) Pragian-lower Emsian) Xujiachong Formation, near Xujiachong village, Qujing District, eastern Yunnan, South China. In three dimensions, the branching system comprises a robust creeping main axis and comparatively slender erect lateral axes inserted oppositely or alternately. The lateral axes depart at right angles from the main axis. Towards the apex, the main axis is perhaps erect with the lateral axes attached at smaller angles. The lateral axes dichotomize equally one to three times in different planes and decrease in diameter and length acropetally. They bear sparse and irregular tiny spines. Apices of a pair of distal lateral axes curve in opposite directions and each terminates in a rounded to reniform sporangium. The sporangium dehisces into two equal valves along an indistinct convex marginal thickening. The xylem is possibly centrarch. This plant fits Hsüa in branching pattern, sporangial characters and xylem maturation. Hsüa deflexa sp. nov. differs mainly from the type species H.  robusta in the presence of axial spines, perpendicular extension of lateral axes from the main axis and curving of distal lateral axes. Based on the possibly centrarch xylem and terminal sporangium, this plant relates to the rhyniophytes ( sensu Banks, 1968). In view of the equal sporangial valves with marginal thickenings it resembles the zosterophyllophytes ( sensu Banks, 1968). Hsüa is now treated as incertae sedis .  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 142 , 255−271.  相似文献   

8.
记述了云南沾益地区下泥盆统穿洞组肺鱼化石一新种——多脊混磨鱼(Tarachomylax multicostatus sp.nov.),归入标本包括一件左上齿板、一块B骨、一块可能是3骨的骨片和6个零散鳞片。主要特征:齿板内侧及后侧边缘被小齿(denticles)覆盖;齿脊11-12列,齿板中缘与最后一列齿脊夹角约135°;内翼骨侧凹不明显,后侧部窄小呈尖状;B骨和J骨上的前凹线沟相连;鳞片出露区与被覆压区之间有小齿瘤带。  相似文献   

9.
描述了早泥盆世的3个属种,其中节甲鱼类Yujiangolepisliujingensisgen.etsp.nov.采自广西六景,Buchanosteussp.及胴甲鱼类?Chuchinolepissp.采自广西玉林。该3件标本均产自海相地层中,与海相无脊椎动物化石共生。还讨论了华南区几个主要产脊椎动物化石(包括脊椎动物微体化石)剖面的生物地层对比。  相似文献   

10.
中国泥盆纪含鱼化石地层的世界对比   总被引:2,自引:0,他引:2  
简要回顾泥盆纪含鱼化石地层分层的进展及现状,总结中国泥盆纪含鱼化石地层的层位,横向地比较了主要鱼化石的系统关系,再结合具体的地质历史背景,对比世界有关的地层。  相似文献   

11.
早泥盆世始叶蕨(新属)及叶子起源的讨论   总被引:7,自引:0,他引:7  
本文报道了滇东南文山地区下泥盆统坡松冲组(西根阶)地层中一陆生植物新属,种-纤细始叶蕨(Eophyllophyton bellum gen.et sp.nov),植物体矮小,多次二叉分枝,远端枝二列互生长出次一级二叉分枝为主的末级枝,枝系起源叶顶生成侧生,多次分叉,缩合,扁化,蹼化并部分并合,生殖单位可下垂,由二枚顶端内卷的孢子叶组成,孢子囊圆至肾形,沿远,端加厚带开裂,成列侧生在孢子叶相对面的叶轴上,上述特征表明新植物远比同期的莱尼类,三枝蕨类和工蕨类复杂和进化,并显示出和工蕨类的某些亲缘关系,文内还探讨了枝系起源叶(大型叶)的发生和演化。  相似文献   

12.
A new genus and species, Eophyllophyton bellum, is described from the Posongchong Formation (Siegenian) of the Lower Devonian in Wenshan cfistrict, Yunnan, China This plant bears lateral branching laminate structures interpreted as leaves, which are believed to derive from lateral axial branching systems In addition similarly organised sporophylls are considered homologous to these leaves. In the possession of these vegetative leaves and sporophylls Eophyllophyton, is significantly more advanced than any other Siegenian taxon.  相似文献   

13.
A new genus and species, Gumuia zyzzata is found in the Posonchong Formation of the Lower Devonian (Siegenian) from Wenshan district of Yunnan, China. It has both lateral and terminal sporangia. Successive sporangia develop on alternate sides of short axes near the hases of preceding sporangia, producing a zigzag fertile organization. The author supposes that it is a sympodium Opposite sporangia are suppositionally referred to the result from condensation of the axis between alternate sporangia. The new plant is tentatively referred to a putative zosterophyll.  相似文献   

14.
<正> 目前,泥盆纪星骨鱼科化石除非洲和南极地区尚未发现外,世界其它各地均有发现,但化石产地并不多.其时代从早泥盆世一直延续到晚泥盆世早期,多数出现在早—中泥盆世.所有化石全部产于海相地层.据现有资料统计,已经发现和描述的只有5个属,即 Asterosteus, Gemuendina, Jagorina, Ohioaspis, Bolivosteus,分布在德国(早泥盆世),美国(中泥盆世),加拿大(中泥盆世),澳大利亚(早一中泥盆世),土耳其(中泥盆世)和玻利维亚(中泥盆世).  相似文献   

15.
十年前在云南省早泥盆世的地层中发现了轮生钩藻(Uncataella verticillata),限于当时的材料,其分类位置未定。本研究所用材料采自它的模式标本产地,化石植物保存良好,首次发现了着生在植物体上的雌性生殖器官——藏卵器。根据藏卵器和植物体其它部分显示的形态特征,本文修订了它的原始描述并对其系统位置进行了探讨,认为轮生钩藻是一种原始的轮藻植物,很可能属于直立轮藻目直立轮藻科中的一个成员。  相似文献   

16.
云南省昭通市东北郊箐门出露了一条比较完整的泥盆系浅海相地层剖面,下、中、上三个统均有出露,浅海底栖生物化石丰富,研究基础也相对较好,是研究滇东北地区泥盆纪地层的一条理想剖面。由于地层剖面比较长,沉积厚度比较大,此前我们已经描述了早泥盆世和中泥盆世早期的四射珊瑚,本文继续描述该剖面的中泥盆世晚期的地层及其四射珊瑚,讨论它们的地层划分、珊瑚群对比与古生物地理。至于晚泥盆世的珊瑚,由于篇幅的关系,我们拟另文继续描述。  相似文献   

17.
滇西早泥盆世大瓣鱼科(Macropetalichthyidae)化石的发现   总被引:4,自引:2,他引:2  
<正> 泥盆纪的大瓣鱼化石目前除在南美和非洲尚未发现外,在全球其他各洲分布甚为广泛.它的分布时代可由早泥盆世延续到晚泥盆世.据统计目前发现的该科化石已达12个属.我国目前发现的大瓣鱼科化石共有5个属种,分布于华南的下、中泥盆统,主要发现于下泥盆统.  相似文献   

18.
The Devonian marine and non marine deposits were widely distributed in East Yunnan, where rich marine faunas and floras were present. The Middle and early Upper Devonian miospores of Eastern Yunnan were also abundant and usually well- preserved. The present paper provides both analysis of qualitative and quantitative composition development of Middle and early Upper Devonian spore assemblage in Eastern Yunnan, and a palynological zonatlon containing four successive assemblage zones: 1.Zone of Calyptosporites velatus-Rhabdosporites langii (VL); 2. Zone of Archaeozonotriletes variabilis-Calyptosporites proteus (VP); 3. Zone of Geminospora lemurata-Cristatisporites triangulatus (LT); 4. Zone of Archaeoperisaccus ovalis-Lagenicula bullosum (OB). The Middle and early Upper Devonian spore assemblages of Eastern Yunnan may be compared with those in South China and West Qinling. The spore zonation possesses stratigraphical dating of the Devonian megafloras of the region, particularly those from the Middle and Upper Devonian. The proposed spore zonation is closely compared with that erected for the Middle and early Upper Devonian of Old Sandstone Continent and adjacent Region. Based on palynological data, the reconstruction of Paleogeography and Paleoecology are discussed.  相似文献   

19.
This paper describes a new plant—Stachyophyton yunnanense gen. et sp. nov., from Posongchong Formation (Siegenian) of the Lower Devonian in Wenshan district, Yunnan, China. This plant shows some similar organization in fertile region and sterile parts in comparison with other Devonian genera (Protolepidodendron, Colpodexylon, Leclercqia, Enigmophyton, Krithodeophyton). It may be that the plant represents an intermediate stage in evolution between Enigmophyton and Krithodeophyton, and shows perhaps a certain affinity to lycopods. According to the salient features of Stachyophyton, it can not be, at present, placed in any group known in vascular plant. It can be assigned to definite position of taxon basing on much fossils record and further studies.  相似文献   

20.
云南丽江早泥盆世棘鱼类微体化石的首次报道   总被引:1,自引:0,他引:1  
记述了云南丽江县鸣音区阿冷初早泥盆世山江组 (Lochkovian EarlyPragian)和阿冷初组(Middle LatePragian)棘鱼亚纲微体化石。这些化石被归属于 4属 5种 ,其中包含 1新属 2新种。这是西藏—滇西区棘鱼类化石的首次报道。不同于华南区棘鱼类的组成 ,丽江早泥盆世棘鱼类以栅棘鱼目属种为主 ,缺少锉棘鱼目属种。它与国外对比 ,则与澳大利亚新南威尔士中部同时代的棘鱼类表现出较多的相似性  相似文献   

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