云南腾冲上新统芒棒组植物分散角质层研究

在云南腾冲上新统芒棒组中发现保存较好的植物分散角质层,共识别出7种:Reticutissolida,Reticutis tylotis,Fundicutis verriculis,Lusaticutis arizelis,Piliparicutis anfracta,Discrepoparicutis elongata,Enormicutis torquata,可归于6属,4亚类,4类,1个大类,表现出上叶角质层类型和下叶角质层类型的组合特征及上叶角质层类型的优先保存情况。从表皮细胞形态及气孔器等微观特征上看,具气孔的4种之间有着明显的差别,表明它们可能分别来自不同的母体植物;其中3种角质层的母体植物极有可能为被子植物,并处于优势地位。滇西当时温暖湿润的热带-亚热带、暖温带气候,为分散角质层的母体植物提供了良好的生存条件。而该区植物分散角质层的发现为分析其母体植物和重建古环境提供微体植物化石证据。     

分散角质层的分类和命名*

简略讨论了分散角质层对地层学、古生物学和古环境的意义;简述了气孔器的形态学、发生学和形态一发生学的分类;在介绍并讨论了分散角质层的分类原则和命名方法的基础上,提出了新的分类方案.     

中国植物化石角质层研究综述

总结近30年来中国大陆植物化石角质层研究的进展,介绍角质层分析的3个主要研究方向:植物化石表皮微细构造研究、植物化石气孔参数与大气CO2和气候变化研究以及植物化石角质层地球化学特征研究.举出众多典型实例,提出植物化石角质层分析的研究展望.     

水杉属和红杉属化石叶表皮鉴定参照系的特殊性

杉科植物的许多属种在小枝的形态和叶片排列上相似,而杉科植物的化石标本多保存为枝叶形式。表皮的特征作为压型化石枝叶标本细胞信息的重要来源,甚至是惟一来源。一直作为杉科植物化石分类鉴定的主要依据。水杉和北美红杉分别是水杉属和红杉属植物化石的惟一现存最近亲缘种,以往关于北美红杉的气孔分布和排列等方面的报道存在分歧,根据作者的研究,北美红杉的表皮特征变异幅度非常广。水杉的气孔分布也与以往报道有差异。利用表皮的特征鉴定杉科植物化石时;不同的处理方法和处理时间,角质层的完整程度和观察数量等均可以影响植物表皮特征的正确获取。     

骨碎补科植物叶表皮特征及其系统学意义

基于骨碎补科(Davalliaceae)植物属的界定和属下等级的划分一直存在较大争议,本研究首次对骨碎补科6属39种(秦仁昌系统)植物的叶表皮进行了扫描电镜观察。结果显示,骨碎补科有9种类型的角质层,其中,阴石蕨属(Humata)的角质层有密集的孔状凹陷结构;Wibelia条纹突起较厚,排列整齐且细密紧致;广义钻毛蕨属(Davallodes)内存在多种角质层类型,需要在属下进一步细分。本研究还根据角质层特征讨论了骨碎补科与一些近缘种类的关系。角质层特征是骨碎补科内种属分类的重要依据,而保卫细胞形状和气孔密度,均不能用来界定骨碎补科的属和种。本研究按角质层分类的结果与Kato和Tsutsumi的分子系统学分类观点一致。     

甘肃永昌早二叠世两种科达叶的微细构造及古大气CO_2浓度重建

角质层微细构造是鉴定植物属种的重要特征之一,近年来又在古气候恢复中得到广泛应用。从甘肃永昌下二叠统采获了角质层保存较好的两种科达叶化石,详细分析了表皮微细构造特征,并结合其外形特征进行了属种鉴定:其中一种鉴定为淮南科达(Cordaites huainanensis Chen),另建立了一新种,命名为永昌科达(Cordaites yongchangensis sp.nov.)。本文选取与化石标本的宏观形态和角质层微观形态较为相似的长叶竹柏(Podocarpus fleuryi Hickel)作为其现存最近对应种,初次尝试利用化石气孔特征重建了甘肃永昌早二叠世的古大气CO2浓度。     

云南保山上新统黄背栎Quercus Pannosa Hand.-Mazz.角质层特征及古环境意义

在滇西保山上新统首次发现了黄背栎(Quercuspannosa)压型化石,并分析了角质层构造。其特征主要为:上表皮无气孔器,表皮细胞为不规则形五边形,垂周壁微弯曲,脉络为网格状,无毛基;下表皮具环列型气孔器,表皮细胞为不规则形五边形,垂周壁微弯曲,脉络为五边形的网格状,具毛基,毛的根部由多细胞组成,毛基部的细胞特化成辐射状。利用现存最近亲缘种(NLRspecies)原理,并比较化石和现生Q.pannosa角质层特征,推断上新世Q.pannosa在羊邑生长的古环境比现生Q.pannosa生存的冷湿气候相对干旱,且化石Q.pannosa为近原地埋藏。     

黑龙江渐新世银杏大化石及其古气候和植物地理意义

首次报道我国渐新世银杏属植物叶化石。化石采自黑龙江汤原县太平川剖面宝泉岭组,角质层保存状态良好。叶为下气孔式。上表皮细胞垂周壁平直,平周壁较平。下表皮大量气孔器不规则地散布于脉间区,形成气孔带;气孔密度约为117个/mm2;气孔器为单环式,保卫细胞下陷,侧副卫细胞角质化强烈并形成乳突。当前材料的形态及显微构造特征与古近纪北半球广泛分布的铁线蕨型银杏Ginkgo adiantoides(Ung.)Heer emend.Flo-rin(auctorum multorum)基本一致。这是我国目前已知年代最新的银杏大化石记录,对于探究银杏属在我国新生代的分布、迁徙以及当时相关的古植物地理和气候环境等具有重要意义。     

化石植物研究方法简介

古植物学是研究古代植物和它们生活的科学。重现植物界历史的方法之一是研究岩层中的化石植物。植物以各种形式保存在地壳之中,在保存期间发生了各种物理、化学变化。不同的环境和沉积过程也会导致化石出现种种不同的保存形式。针对不同的类型,必须采用不同的技术处理,以便从中提取信息,找出同一植物各分散器官之间的联系,从整体进行研究和重建。１　角质层的处理方法化石角质层为地质史上真正生活过的植物活体上的原物,它与植物生活的环境有一定的联系,可作为探讨属种间的自然亲缘关系的依据。化石角质层有几种处理方法（叶美娜,１…     

浙江下白垩统几种裸子植物化石及其表皮构造研究

在浙江广泛分布的早白垩世火山沉积岩系中,含有较多的各门类化石。植物化石虽颇丰富,但几乎全为印痕化石,且一般保存较差;比mosa (Fontaine) Watson和M.(Manica) papillosa Chow et Tsao两种产自新昌苏秦的松柏类标本(周志炎、曹正尧,1979)。本文记述苏铁类1新种和松柏类叶枝化石3种(其中较完整的标本不多,具有角质层的更是稀罕。至今对植物化石角质层的工作做得很少,已发表的仅有原定为 Manica (Manica) parcera-1旧种、2新种)。它们分别隶属于蕉羽叶(Nilssonia Brongn.),假拟节柏(Pseudofrelopsis     

Cretaceous floras containing angiosperm flowers and fruits from eastern North America

A recent innovation in paleobotanical studies of the Cretaceous has been the use of bulk sediment disaggregation and sieving techniques. This approach has identified numerous Cretaceous floras that contain well-preserved plant fossil debris (“mesofloras”), and many of these have yielded abundant fossil angiosperm flowers, as well as angiosperm fruits, seeds and dispersed stamens. On the Atlantic Coastal Plain of eastern North America recent research has identified a new series of fossil floras of Campanian age from central Georgia. These form part of a rich sequence of mesofloras that range in age from early Aptian (or perhaps late Barremian) to Campanian. Detailed studies of fossil flowers from these floras have clarified the systematic relationships of Cretaceous angiosperms and identified source plants of several characteristic dispersed angiosperm pollen grains. Taxa referable to extant angiosperm families appear suddenly in the Albian and Cenomanian, and the number of extant angiosperm families that can be recognized increases rapidly through the Late Cretaceous. Based on the record of Cretaceous fossil flowers, “modernization” of angiosperm lineages occurred much earlier than had been inferred previously from studies of dispersed fossil pollen. Major extinct monophyletic “higher” taxa of Cretaceous angiosperms have not yet been recognized.     

First reliable record of a fossil species of Anthomyiidae (Diptera), with comments on the definition of recent and fossil clades in phylogenetic classification

All previous records of fossil Anthomyiidae are shown to be unsubstantiated. A female anthomyiid of a new genus and species is hereby described from a piece of Dominican amber (Upper Eocene-Oligocene). Character analysis suggests that the fossil, Coenosopsites poinari gen. & sp. nov. , belongs to a Neotropical clade with two recent genera, Phaonantho Albuquerque and Coenosopsia Malloch. Evidence for a sister-group relationship between Coenosopsites poinari and the genus Coenosopsia is provided. Clades are the only acceptable units of phylogenetic classification. Combining fossil and recent clades in phylogenetic classification requires them to be temporally delimited. Proper application of phylogenetic definitions is essential for this purpose. It is proposed that the units of phylogenetic classification should be taxa for recent clades and plesia for fossil clades. A taxon is defined as node-based with reference to its recent species, while a plesion is defined as apomorphy-based. The term lineage is proposed for a recent clade defined as stem-based with reference to its recent sister group. Individual recent species represent clades that can be incorporated into phylogenetic classification as minimal taxon units. Individual fossil species may not represent clades and thus do not count as proper units of phylogenetic classification. However, the names of fossil species are readily construed also to signify plesia with the fossil species as their only known component. As such, they are proper units of phylogenetic classification.     

化石菌类的分类系统

讨论化石菌类及其孢子的分类系统,即自然分类及人为分类系统,自然分类系统在孢粉学发展初期曾被广泛采用,随着孢粉学的发展,一些化石菌类缺乏明显的自然属性,其分类采用人为分类系统,Elsik依据细胞数目及萌发器特征首次建立了化石菌类的人类分类系统,但该分类系统未被广泛接受,Norris研究了加拿大第三纪菌类化石,但他未将菌类孢子的形态属归入相应的科、目和纲,宋之琛主要根据菌类孢子的萌发器特征,建立了菌类孢子分类系统,并将菌类孢子及其遗留体分为以下类型：无萌发器类型,单孔类型,双孔类型,三孔类型或三岐菌丝类型,子囊果状或多细胞类型及其他,依据宋之琛及Elsik分类系统及隔壁孔的特征,系统整理了已发现的中国第三纪化石菌类孢子,并将其归入相应的分类位置。     

The new species Ettingshausenia sarbaensis (Angiospermae) from the Cenomanian-Turonian of Western Kazakhstan in light of the problem of classification of dispersed cretaceous Platanus-like leaves

Based on morphological and epidermal characters of the leaf, a new species, Ettingshausenia sarbaensis sp. nov., from the Cenomanian-Turonian of western Kazakhstan is described. In fossil Platanus-like leaves, the unique epidermal structure, with the combination of encyclocytic, laterocytic, and paracytic stomata and the presence of trichomes on one or from two to seven epidermal cells, is shown for the first time. Based on variations in morphological and epidermal characters, two morphotypes corresponding to groups of sun and shade leaves are recognized. The expediency of consideration of dispersed Cretaceous Platanus-like leaves within the framework of morphological classification of leaves is discussed.     

The first Loranthaceae fossils from Africa

An ongoing re-investigation of the early Miocene Saldanha Bay (South Africa) palynoflora, using combined light and scanning electron microscopy (single grain method), is revealing several pollen types new to the African fossil record. One of the elements identified is Loranthaceae pollen. These grains represent the first and only fossil record of Loranthaceae in Africa. The fossil pollen grains resemble those produced by the core Lorantheae and are comparable to recent Asian as well as some African taxa/lineages. Molecular and fossil signals indicate that Loranthaceae dispersed into Africa via Asia sometime during the Eocene. The present host range of African Loranthaceae and the composition of the palynoflora suggest that the fossil had a range of potential host taxa to parasitise during the early Miocene in the Saldanha Bay region.     

INVESTIGATIONS OF ANGIOSPERMS FROM THE EOCENE OF NORTH AMERICA: A CATKIN WITH JUGLANDACEOUS AFFINITIES

Three specimens of one type of fossil catkin from the Middle Eocene of Tennessee are excellently preserved and have been investigated morphologically. The flowers on these catkins are subtended by elongate, three-lobed bracts, are exclusively staminate, and have three conspicuous, obovate, perianth parts that bear large peltate scales. The stamens are well preserved and contain triporate pollen grains that are equivalent to the dispersed pollen genus Momipites. Floral morphology, cuticular features, and pollen indicate close affinities with the extant genera Engelhardia, Oreomunnea, and Alfaroa of the Juglandaceae; but because the fossil catkins are distinct and are a dispersed plant organ, they are placed in a new form genus: Eokachyra. These fossil flowers represent a rare opportunity to correlate the micro- and macrofossil record and to compare the relative rates of evolution of these features. The fossil catkins also demonstrate that much structural information may be gained from the study of fossil angiosperm flowers. The similarities between the staminate flowers of the fossil catkins and the staminate flowers of Engelhardia, Oreomunnea, and Alfaroa confirm the idea that this complex has had a long evolutionary history and suggest that the pollination system of certain extant genera was well developed during Middle Eocene times.     

黔西滇东早三叠世早期Annalepis(脊囊属)的出现及其地层意义

为解决早三叠世卡以头组地质时代和植物组合问题,对采于黔西滇东地区两条二叠系-三叠系海陆交互相界线剖面卡以头组中、下部的植物化石Annalepis(脊囊属)进行深入研究。与Annalepis同层或上部层位见有早三叠世早期的海相双壳类、介形类、腕足类、菊石类及大羽羊齿植物群残余分子,因此可以确定Annalepis在该地区出现于早三叠世早期的印度期(Induan),说明卡以头组(至少中、下部)地质时代属早三叠世早期。推测我国南方的Annalepis在早三叠世始于黔西滇东,随后向北迁移、中三叠世广布于长江中下游地区。建立由早三叠世An-nalepis和大羽羊齿植物群残存分子共同构成的我国南方早三叠世早期植物组合,填补了早三叠世晚期岭文组与晚二叠世B期Gigantonoclea guizhouensis-Ullmannia cf.bronnia-Annularia pinglouensis组合之间的空白。     

A Middle-Late Eocene inflorescence of Caryophyllaceae from Tasmania, Australia

A new genus and species (Caryophylloflora paleogenica genus and species nova G. J. Jord. & Macphail) are proposed for a fossil inflorescence found in Middle-Late Eocene sediments at Locharbour, northeastern Tasmania, Australia. A parsimony analysis of 75 extant species of the order Caryophyllales and five outgroups placed the fossil within Caryophyllaceae, either subfamily Alsinoideae or Caryophylloideae. The analysis used molecular (rbcL and/or matK), morphological, and anatomical data for the extant species and morphological data for the fossil. Tests on extant species imply that the placement of the fossil should be convincing. The fossil appears to be of a lineage distinct from any extant Australian Caryophyllaceae. In situ pollen are consistent with the form species, Periporopollenites polyoratus. This relatively simple pollen type first appears in Australia and New Zealand in the Late Cretaceous, the oldest known record of the Caryophyllaceae. The last appearance of P. polyoratus in Australia is in the Oligocene, and extant Australian members of the Caryophyllaceae are best interpreted as having evolved from species that dispersed from elsewhere during the Neogene or Quaternary.