On Some Dispersed Cordaitean Cuticles from Cathaysian Flora in the Permian of China and Their Significance

Although the research on Cordaites of the Cathaysian Flora in China started early in 1883, the study of the cordaitean cuticles began late in 1991. Up to now, four types of cordaitean cuticles in situ and three types of dispersed ones have been reported from the Cathaysian Flora in China. However compared with the Euramerican Flora, the research work on cordaitean cuticles from the Cathaysian Flora in China is much more insufficient. In this paper, three kinds of dispersed cordaitean cuticles are described in detail from the Permian coal-bearing strata in China. Among these cuticles two kinds are collected from the roof shale of Coal Seam No. A(1) in Shanxi Formation (Lower Permian) in Xinzhuangzhi Coal Mine of Huainan, Anhui Province, southern border of North China Subprovince of the Cathaysian Flora in China. The third one was collected from Coal Seam No. 11 in the top of Longtan Formation (lower Upper Permian) in Dahebian Coal Mine of Shuicheng Mining District, Guizhou Province, South China Subprovince of the Cathaysian Flora in China. Comparison of these three kinds of cordaitean cuticles with the known ones from the Cathaysian Flora in China and from the Euramerican Flora is made. The authors consider that they are all new types of cordaitean cuticles. The significance they bear on palaeobotany is discussed.

Yuzhou Flora——A hidden gem of the Middle and Late Cathaysian Flora

The Yuzhou Flora of the southern North China Platform possesses the typical regional features of the Middle and Late Cathaysian Flora.For a long time during the Permian,this area was located on shoreline marine tidal flats and deltas at low latitudes with a warm and humid climate.Consequently,many successive layers with abundant well-preserved plant fossils and a complete evolutionary sequence were developed.This is a unique and ideal place to study the Middle and Late Cathaysian Flora.We have recognized 111 genera and 307 species from this flora.The rapid morphological evolution and uninterrupted stratigraphic succession of Lobatannularia(Sphenophytes) make this group one of the bases for biostratigraphic divisions of the Permian System of the North China Platform.Ninety percent of Pteridophytes belong to the order Marattiales,which are well developed during the early and middle stages of the Yuzhou Flora but experience a sudden decline during the late stage.Ancient Pteridospermatophytes only flourished during the Middle Permian whereas advanced Peltaspermales are extremely well developed at the end of the early Late Permian.Among them Shenzhouphyllum is one of characteristic elements in the late stage of the Yuzhou Flora.The Cycadophytes evolved relatively early in this area and they differentiated and proliferated during the late Middle to early Late Permian.The number of species of Ginkgophytes is small but this group is extremely abundant,especially in the early Late Permian.The Gigantopteridales(preangiosperms) is a very important and unique group in the Yuzhou Flora.Based upon their venation and leaf architecture,this group can be divided into three evolutionary stages,i.e.,appearance and differentiation,first flourishing,and second flourishing and sudden disappearance,which form the basis for biostratigraphic division and correlation of the Permian System of the North China Platform.Based upon the evolutionary trend of venation pattern and leaf architecture,we propose some taxonomic changes at the generic level.The Yuzhou Flora emerged at the middle Early Permian(Zisongian) and suddenly disappeared at the early Late Permian(Wujiapingian).It is later replaced by the Euro-American Zechstein flora in the late Late Permian.The Yuzhou Flora is divided into three(early,middle and late) stages based upon the cyclic development of its plant groups.Five fossil plant assemblage zones are recognized from the Yuzhou Flora based upon the succession of each group and their combined characters in different layers.

Lopingian mixed floras from Linxi Formation in Soron area,Inner Mongolia

A lot of well-preserved plants from the Linxi Formation are collected in the Soron area,Inner Mongolia,consisting of 34 species of 16 genera. They are Late Permian in age. The flora is characterized by a lot of Angaran plants,such as Paracalamites,Comia,Rhachiphyllum,Iniopteris,Rufloria,etc. Some Cathaysian elements,such as Lobatannularia lingulata,L. multifolia,Fascipteris Cathaysiantus,F. densata,Taeniopteris szei,Cladophlebis liulinensis and C. permica,are also mixed within the present flora. This indicates that the Soron of Inner Mongolia was located in the sector between the Angaran and Cathysian floristic provinces in Lopingian. It is beneficial for depicting the location and the evolution of the Solenker--Xar Moron suture zone in the phytogeographic view. The transmigration of tropical and subtropical Cathaysian plants to the north indicates that the Paleoasian Ocean was closed during the late Permian along the suture zone.

Roof Shale Flora of Coal Seam 6 from the Asselian(Lower Permian) Taiyuan Formation of the Wuda Coalfield,Inner Mongolia and Its Ecostratigraphic Significance

Roof shale floras help understand the transition of vegetational landscapes from a peat–forming environment to a clastic one, but are seldom investigated in the Cathaysian province（typical present day China and East Asia）. Here the roof shale flora of Coal Seam 6 from the lower Permian Taiyuan Formation of the Wuda Coalfield, Inner Mongolia, is systematically described and its ecostratigraphic and phytogeographic implications are discussed. The flora is composed of seven plant groups, including Lepidodendrales, Medullosales, Gigantopteridales, Peltaspermales, Noeggerathiales, Cordaitales and Cycadales. Many of these taxa are also documented in Euramerica, and the floral composition indicates a more intimate relationship between Cathaysia and Euramerica during the Cisuralian than previously thought. However, there are few genera and species in common with those of the underlying peat–forming flora. Moreover, the flora is hardly comparable with the commonly known flora of the Taiyuan Formation. Such assemblage differences are very likely due to changes of taphonomic and environmental phases, rather than evolutionary floral succession. For a full and more precise understanding of the floral composition, succession and the floristic discrepancy in different depositional environments, an ecostratigraphic investigation on the Late Palaeozoic of Cathaysia is advocated.

Anatomically-preserved Lepidodendralean Plants from Permian Coal Balls of China: Sigillariopsis Scott

Three kinds of anatomically_preserved lepidodendralean leaves from Permian coal balls of China were studied. They all have double xylem strands, which is consistent with the genus Sigillariopsis Scott. Compared with the species of Sigillariopsis , they are considered as three new species: S. shanxiensis sp. nov. and S. taiyuanensis sp. nov. from Coal Seam 7 in the upper part of the Taiyuan Formation (lower Lower Permian), Xishan Coal Field, Taiyuan, Shanxi Province and S. guizhouensis sp. nov. from Coal Seam 1 in the Wangjiazhai Formation (upper Upper Permian), Shuicheng Coal Mining District, Guizhou Province. Based on the associated organs of lepidodendraleans other than leaves and the information of the Euramerican lepidodendraleans, the affinities of the three new species of Sigillariopsis are discussed and they are probably leaves of Sigillaria Brongniart. In Euramerican Flora, Sigillaria (including its leaves Sigillariopsis ) mainly lived in the Carboniferous period and in the Cathaysian Flora they lived in the Upper Carboniferous to upper Upper Permian periods in rare localities. The leaves and fertile organs of Sigillaria have not been reported from the Cathaysian Flora to date. Three new species of the Permian anatomically_preserved leaves of Sigillaria not only increase the diversity of the Cathaysian sigillarian but also bear important significance on the evolution of sigillarian plants and the relationship of the Cathaysian and Euramerican lepidodendraleans.

Anatomical Structure of Leaf Cushion of Lepidodendron lepidophloides Yao

The isolated and anatomically_preserved lepidodendralean leaf cushions were described from coal balls in Wangjiazhai Formation (upper Upper Permian) in western Guizhou Province. These leaf cushions are very similar to Lepidodendron lepidophloides Yao both in size and morphology. They probably belong to the same species in different preservative condition. Comparisons on morphology and anatomy of L. lepidophloides and lepidodendralean leaf cushion genera, such as Lepidodendron, Lepidophloios, Sigillaria and Cathaysiodendron revealed that L. lepidophloides possesses mixed features of all these genera and it can not be assigned into any of them without doubt. It probably represents a new genus. Because the anatomical features of the other parts of the stem as well as the fertile organs related to these leaf cushions are unknown, the specific name L. lepidophloides is adopted. We leave this taxonomic problem open till the relationship between these leaf cushions and the stem and fertile organs become clear. This is the first report on the detailed anatomical features of the Cathaysian lepidodendralean leaf cushions.

内蒙古东乌珠穆沁旗满都胡宝拉格地区早—中二叠世华夏植物群的发现及地质意义

内蒙古东乌珠穆沁旗满都胡宝拉格地区位于贺根山北东42°方向约240km处。在该地区首次发现了早—中二叠世地层(P1-2),其中富含华夏植物群化石,已鉴定出7属11种,可与华北板块同期植物群进行对比,时代确定为早—中二叠世。该发现为进一步认识西伯利亚与华北板块之间缝合线的位置和时间提供了重要的科学依据。据此认为两大板块缝合的时间应在早二叠世之前。

甘肃玉门华夏和安加拉混生植物群的发现及其意义

本文报道了发现于甘肃玉门大山口上二叠统肃南组华夏和安加拉混生植物群,含16属26种。根据植物分子的组成,植物群的时代属于晚二叠世早期,相当于二叠纪(三分)的吴家坪期(Wuchiapingian)。这些保存颇佳的植物化石对于研究华夏和安加拉两个植物区系的关系提供了新的依据,具有重要的古植物地理学意义。

中国前晚石炭世植物群的性质--对“前华夏植物群”的讨论

"前华夏植物群"一词由李星学等提出,原义指以西北地区下石炭统(臭牛沟组、靖远组为主)及华南相当地层中的植物总称。作者分析了当前古植物地理区划的有关理论,结合中国的具体情况,提出"前华夏植物群"的涵义不但可以代替欧美植物群中拟鳞木植物群(Lepidodendropsis flora),而且还可能包括自早志留世植物登陆以来至早石炭世,在中国大陆(或称华夏复合大陆)生长的、独立的植物群。文中以晚泥盆世—早石炭世的植物群中独特的科、属、种等地方性土著分子为例,以当前古植物地理区的有关理论为依据,认为"前华夏植物群区"可以从以往的"欧美植物群"或"拟鳞木植物群"区中单独划分出来成为独立的植物地理区。

广东种子植物区系地理成分研究

广东种子植物区系共有２１９科１４３４属４９８６种。其中：①热带区系成分占有较大的比例，约占非世界属的６２．３％，表明广东区系受到热带区系的强烈渗透，次之为亚热带（至亚热带山地）成分约占３２．２％，及中国特有分布占５．６％；②以单型属（７２属），单种属（５８５属）和寡种属（５６２属）占绝对优势，共占８５．０％，充分显示了广东区系的古老性和过渡性特点；③从区系组成和植被结构的特征成分来看，以华夏植物区系成分为主，包括：亚热带分布，亚热带山地分布，中国特有分布，东亚—北美间断分布，及一些亚洲热带分布中以亚热带为主的属：④在这些属中有东亚特有属１３２属，中国特有属７５属以及华南—西南—中南半岛特有属６８属等；这些属的存在毫无疑问地说明，广东区系是华夏植物区系的核心地区之一，同时也显示了热带区系与亚热带区系有着不可分隔的统一性。

广东饶平植物区系的研究

对广东省汕头市饶平植物区系组成与基本特点作了研究，饶平区系的表征科为樟科（Ｌａｕｒａｃｅａｅ）、壳斗科（Ｆａｇａｃｅａｅ）、山茶科（Ｔｈｅａｃｅａｅ）、紫金牛科（Ｍｙｒｓｉｎａｃｅａｅ）等，反映了区系的亚热带性质。在饶平植物区系中，热带性和温带性成分均为对本区系的侵入，饶平区系隶属于古热带区系中的华南亚区。阐述了饶平植物区系与相邻地区植物区系之间的联系。

用聚类分析法探讨中国二叠纪华夏植物群的植物地理区划

用聚类分析法对中国二叠纪华夏植物群２５ 个分布区、８３１ 种进行古生物地理区划，与以往定性分析结果相互借鉴。结果表明原划分方案总体上得到验证，华北区内似存在更次一级的植物地理单元。

论我国二叠纪华夏植物群岛屿生物地理平衡理论的应用

岛屿生物地理平衡理论已被初步证明能够运用于古生物地理学研究。但由于地质古生物学资料的局限性 ,目前运用这一理论对地史生物群进行相关研究主要表现在对相关问题进行检验。文章总结了对我国二叠纪华夏植物群进行岛屿生物地理平衡理论偿试性研究的各项成果 ,指出开展此项研究所需的地质古生物学基础和目前存在的一些缺陷。此外 。

Anatomical Structures of " Lepidodendron " pulchrum Zhang in Coal-balls from the Taiyuan Formation (Lower Lower Permian) in Shandong Province, North China

This study reports the anatomical structures of a kind of lepidodendralean stem in coal balls from the early Early Permian Taiyuan Formation in Yanzhou Mining District, southwestern Shandong Province, North China. The leaf cushion is slightly rhomboid in outline with a height of 9 - 10 mm and a width of 7.5 9.0 mm and its lower sides are slightly longer than the upper ones. The top and basic angles of the leaf cushion are truncate and the basic angle is slightly elongate. The upper part of the leaf cushion is strongly high-rising. The leaf sear is large and lenticular in shape. The leaf trace is wide and V-shaped in the leaf scar, and horizontally elongate within the leaf cushion. The leaf trace and lateral parichnos strand extend at a nearly horizontal course outward within the leaf cushion. The ligular pit is deep and extends outward at an oblique course and its aperture is located near the top angle of the leaf scar. No infrafoliar parichnos strands are present. The stem is probably siphonostelic and its pith is probably parenchymatous. The primary xylem is exarch with a nearly smooth outer margin. Only the outer cortex is present and it consists of alternately-arranged radial cell bands and gaps within which the are-shaped or V-shaped leaf traces can be seen. The concave side of the leaf trace is toward the center of the stem. No bundle sheath is developed. Periderm is well-developed and consists of phelloderm and phellem in nearly equal thickness. Compared with the lepidodendralean stems of the Cathaysian and Euramerican Floras, the present specimens are most close to an impression-compression species Lepidodendron pulchrum Zhang in morphology of the leaf cushion and they are put into this species temporarily. Whether the present specimens or the type specimens of L. pulchrum are very different from Lepidodendron Sternburg sensu DiMichele, thus the correct nomenclature and classification of L. pulchrum needs to be reconsidered based on the study of better- and anatomically-preserved stems and fertile organs in the future. Because 'L'. pulchrum possesses the mixed features of several genera of Euramerican lepidodendralean stems, it bears significance to study the origin and evolution of the Cathaysian lepidodendralean lycopods.

全球植物区系的间断分布问题

华夏植物区系以其拥有大量的原始类群，众多的特有科属和完整的系统发育各阶段的类群代表而著称．华夏植物区系与澳洲区系、非洲区系、南美区系、北美区系、欧洲区系、以及亚洲的印度区系、马来西亚区系及日本区系都有密切的联系．这种联系可追溯到中生代的前期，当联合大陆分裂之前，有花植物的原始代表就已经存在，到了白垩纪各大陆块的植物获得继续发展．因此间断分布不仅见于东亚—北美，同时也见于东亚—澳洲、东亚—非洲、东亚—南美，非洲—南美、非洲—澳洲，澳洲—南美等．

黑龙江伊春红山华夏—安加拉混生植物群

系统研究了黑龙江省伊春红山地区晚二叠世红山组植物群,认为其性质为华夏—安加拉混生植物群。华夏植物区与安加拉植物区的界限,应以内蒙古陆及其东、西延展部分为界。

晚古生代的科达科——起源和演化的研究

科达科Cordaitaceae植物广泛分布于晚古生代的欧美植物区和华夏植物区,目前包括3个自然属:Mesoxylon、Pennsylvanioxylon和Shanxioxylon。根据目前资料,欧美植物区只见有前两个属,而在华夏植物区这3个属则都有分布。本文详细讨论了这3个属的茎的初生构造、雄性球果穗及胚珠,认为在这3个属中Mesoxylon最原始,Pennsylvanioxylon较进化,Shanxioxylon的茎的初生构造虽具一定的原始性(如具中始式叶迹),但其生殖器官却相当进化。因此,本文提出Shanxioxylon是一种可塑性较强的科达植物,能够适应环境的变化,最终有可能演化为新的植物类群,如某种早期的松杉类;Pennsylvan-ioxylon则是一种较为特化的植物,其结局是走向绝灭。结合地层中科达科化石的分布情况,本文认为最早出现的科达植物应是Mesoxylon,它可能是由某种前裸子植物演化而来,再由其演化至Shanxioxylon和Pennsylvanioxylon。由于气候和地理环境的不同,华夏植物区和欧美植物区的科达植物各自沿着不同的路线进行演化。其中,欧美植物区科达科的演化路线可能为:某种前裸子植物→Mesoxylon的较原始类型(如M.multirame,Mitrospermun bulbosum)→Mesoxylon的较进化的类型(如M.thomp-sonii)→Pennsylvanioxylon的较原始类型(如P.iowense)

亚洲热带-亚热带植物区系与植被的整体性(英文)

(1)中国植物区系不是来自北方,也不是来自热带,不能把中国植物区系看成是南北植物区系的混合体,它是在中生代起源于华夏古陆.自中生代以来,由于造山运动把华夏古陆与康滇古陆,四川古陆、淮阳古陆,江南古陆、塔里木古陆,华北古陆,北越古陆及印支古陆等联结成一片完整的古陆.北部包括东北南部,内蒙,天山北麓,还有日本本部及朝鲜半岛.南达苏门答腊及加里曼丹.整个亚洲热带和亚热带是一个完整的体系.原始的有花植物从三迭纪以后逐渐在华夏古陆发展起来,白垩纪以后并遍布于现在的热带地区.所谓北极起源的假设不能解析中国植物区系的组成和来源.不仅现代分布于热带和亚热带的植物不可能来自北方,连那些被视为温带成分的,如槭树科,杜鹃花科,忍冬科,榛科,桦木科,胡桃科以及报春花科,龙胆科,紫草科,麂蹄草科,岩梅科等,都是亚热带山区起源的,例如马先蒿属Pedicularis 有80%分布于亚热带山区.(2)中国植物区系不是由热带地区扩展过来的.热带地区分布的专性科及优势科,如龙脑香科等在系统发育方面都是后起的,它来自亚热带起源的更原始的科.再从地史上看,亚洲热带的地史既不稳定又是中生代晚期才升起的,那里不可能产生现在占优势的许多热带科属的远祖,至于热带山地雨林占优势的壳斗科,山茶科,木兰科,金缕梅科等,它们不是热带起源,而是亚热带起源,再扩展到热带,由于白垩纪后期的干旱以及气候分带加剧,才转移到热带中山地带.(3)落叶树不是由低温起源的,当然更不是来自北方或起源于北方,它是由于南方的干旱气候促成的,如木棉,柚木,合欢,厚皮树,苦木,箭毒木等都是证明,那些分布到北温带的栎树,枫香,胡桃,榛,榆,朴树甚至杨树等,都是亚热带山区起源,经过白垩纪后期的干旱而形成的,木材解剖的证据说明了常绿的木兰及朴树等的木材结构比落叶树的木兰及朴树原始得多,针叶树也有类似的现象.落叶松Larix 是亚热带起源的,分布于亚热带的金钱松Pseudolarix 只局限于亚热带,它的落叶肯定不是低温促成,也绝对不是来自北方,而是白垩纪后期的干旱造成的.(4)针叶树的起源问题,历来都认为起源于北方,再向南方迁移,现在看来,也是难以置信的,以北温带最常见的松科为例,松科有10属,全都分布于中国亚热带山区.而在北温带只有冷杉Abies,云杉Picea,落叶松及松4个属,因此,亚热带山区10个属的松科植物,不可能由于冰川的作用,和用第三纪北极区系迁移论的假设来解释.因为南方的特有属油杉Keteleeria,银杉Cathaya,雪松Cedrus 及金钱松,以及分布于东亚及北美亚热带的铁杉Tsuga 和黄杉Pseudotsuga 都是当地起源的,Abies 见于湘南及浙南,亦有花粉见于5万年前的韩江沉积.再从杉科的柳杉Cryptomeria,杉木Cunnighamia,水松Glyptostrobus,Metasequoia,台湾杉Taiwania 以及北美落羽杉Taxodium,红杉Sequoia 及Sequoiaden-dron 都是亚热山区起源,不可能从泛北极或北温带迁来的.再以柏科为例,绝大部份的属都是分布于亚热带,能够到达北极圈附近的,只有一些匍匐状的Junip(?)rus 等个别种类.至于紫杉类的紫杉Taxus,粗榧Cepholotaxur,穗花杉Amentotaxus 当然都是亚热带起源的,而南洋杉Araucaria,罗汉松Podocarpus 及陆均松Dacrydium 等则更不必说了.(5)亚洲热带与亚热带是一个整体,这里的植物区系在起源上是统一的,华夏古陆在三迭纪就已经完整地包括印支半岛,马来半岛,苏门答腊及加里曼丹等地.三迭纪以后,有花植物区系兴起,必然遍布于整个华夏古陆.由于白垩纪以后华夏古陆南部气候变干旱促使植物分布出现重新调整,中国从南到北普遍存在的红层,为这种干旱气候的存在提供佐证,再加上第三纪以后,气候分界和季节分化日趋剧烈,形成了现代热带与亚热带植物分布的格局,喜热的种系留在热带地区,喜温或能抗低温的种系则分布于亚热带和温带,及热带的中山和亚高山.那些白垩纪以后才出现的热带成分如龙脑香科等就只能留在热带,而白垩纪以前的植物如木兰科、金缕梅科,山毛榉科等退到了热带山地,仍有强烈的生命力.至于更古老的种系如昆栏树、水青树等,已处在衰退状态,而残存于一隅.

中国华夏植物区的科达植物化石

总结了过去几十年来，特别是近４０年来有关中国华夏植物区科达植物研究的资料，将中国华夏植物区的科达植物化石归为４种类型：印痕、压型、髓模及矿化化石等。在科达植物各种器官中，分布最广、数量最多、时代延续最长的是其叶化石，最早出现于早石炭世的维宪期（Ｖｉｓｅａｎ），但数量较少，分布零星。在华北，一直到晚石炭世的斯梯芬期（Ｓｔｅｐｈａｎｉａｎ）和早二叠世，科达叶化石数量才逐渐增多，特别在早二叠世，达到最繁荣时期，化石保存类型也多种多样。晚二叠世早期，由于华北地区气候逐渐变得干旱，仅在南部的豫西、两淮和徐州一带尚有较多的科达叶化石。到了晚二叠世晚期，整个华北地区全为干旱气候，已无科达叶化石的记录。华南仅在早二叠世地层中有一定数量的科达叶化石，但种类单调，化石保存类型少。晚二叠世时，仅零星分布于江西中部、广东北部、四川筠连及苏南一带。西北地区在早二叠世时有较多的科达叶化石，晚二叠世时被安加拉型的科达植物（如Ｎｏｅｇｇｅｒａｔｈｉｏｐｓｉｓ）所取代。球果穗化石以及矿化的茎和胚珠（或种子）化石的地质、地理分布则要局限得多，主要见于华北和西北地区晚石炭世和早二叠世地层中。华夏植物区的科达植物化石对于研究科达植物的晚期演化历史?

禹州华夏植物群与含煤地层研究

通过对河南禹州华夏植物群与含煤地层的研究可知,河南省禹州市神垕镇与磨街乡之间的大风口一带,石炭二叠纪含煤地层出露总厚度超过950 m,最多含煤层数达89层,华北与华南所有的含煤层位在这里几乎都可以找到天然露头,成为研究我国华北晚古生代聚煤盆地的一根"铁柱子",对对比河南省煤田地质勘查和地层具有重要的标杆作用.所产植物化石已鉴定有112属306种;其中,137个为新种,分属12个植物类别.此外,剖面上还有多层可用于烧制钧瓷的黏土矿层.