中国连香树科的系统研究——Ⅰ.叶的宏观结构及叶柄维管束变化

本文研究了连香树科(Cercidiphyllaceae)叶的宏观结构,首次报道连香树齿腺体显微结构及晶体类型,并对叶柄维管束的变化作了进一步研究。通过与近缘科的比较,我们认为连香树科的系统演化处于孤立地位,和金缕梅科有较近的亲缘关系,与木兰科较为疏远。     

The earliest fossil evidence of the Hamamelidaceae: Late Cretaceous (Turonian) inflorescences and fruits of Altingioideae

Fossilized pistillate inflorescences, fruits, and pollen grains from the Turonian (～90 million years before present) of New Jersey are described as a new genus, Microaltingia, in the family Hamamelidaceae. The fossils are remarkably preserved in exceptional detail. Several morphological and anatomical characters suggest affinities with Hamamelidaceae. These include capitate inflorescences, florets with a hypanthium, two-carpellate gynoecia, perigynous flowers, tricolpate reticulate pollen, a three-layered carpel wall, scalariform perforation plates with oblique end walls, and scalariform and opposite/alternate intervascular pitting. The gross morphology of pistillate inflorescences, unisexual flowers, phyllome structure, numerous ovules per carpel, and mode of carpel dehiscence indicate affinities with subfamily Altingioideae, which includes the modern genera Liquidambar and Altingia. Cladistic analysis using a previously published morphological matrix and scoring the fossil for available characters supports the position of the fossil as a sister taxon of modern Altingioideae. Although the fossil exhibits a mosaic of characters found within modern Hamamelidaceae, it is not identical to any modern taxon. Based on cladistic analysis, the fossil appears to be a basal "altingioid" that lacks the derived pollen found in extant Altingioideae and retains the more plesiomorphic tricolpate pollen found in the rest of Hamamelidaceae. The floral characters of the fossils, including phyllomes with stomata, short and straight styles, and small perprolate pollen grains, also indicate the possibility of insect pollination.     

Hamamelidaceae: Geographic Distribution,Fossil History and Origin

The family Hamamelidaceae is one of the core (or key) groups for studying the phylogeny of Hamamelids. It is an important taxon for the palaeobotanists and the botanists in discussing the origin and early evolution of the angiosperms owing to its strong differentiation of gross and pollen morphological characters. In this paper, the systematic position, modern distribution pattern and fossil history of the genera are analyzed, and the place and time of origin of the family are discussed according to the principle of the unity between the phylogeny and distribution of plants. The paper consists four parts.     

金缕梅科的种子形态学及其系统学评价

本文利用光学显微镜及扫描电镜在属级水平上观察了金缕梅科全部6亚科中的21属41种1变种植物的种子特征,结果表明：该科的种子形状、颜色、大小及种脐特征在各亚科中有差异(除了双花木亚科与金缕梅亚科的大多数属是一致的)可作为区分亚科的特征之一。根据种皮的特征,可划分为5类：(1)种皮平滑或仅在边缘部分具条纹状纹饰(双花木亚科及金缕梅亚科中大部分属);(2)种皮具条纹状纹饰,条纹有波浪加厚或升高(马蹄荷亚科);(3)种皮具瘤状纹饰或具条纹和瘤状相间排列的纹饰(红花荷亚科);(4)种皮具条一网状纹饰(壳菜果亚科);(5)种皮具网状纹饰(枫香亚科)。种皮纹饰对亚科的划分具有一定意义。此外,还详细观察了该科的种皮结构,确认金缕梅科的种皮由外种皮及内种皮构成,而外种皮又进一步划分为外层、中层和内层,种皮各层的细胞层数对该科的分类价值不大。研究结果还表明：枫香亚科的种子特征明显不同于该科的其它成员。关于枫香亚科的系统位置还需深入研究。     

INVESTIGATIONS OF ANGIOSPERMS FROM THE EOCENE OF NORTH AMERICA: STIPULATE LEAVES OF THE RUBIACEAE INCLUDING A PROBABLE POLYPLOID POPULATION

A comparative study was made of the gross morphology, fine venation and cuticular features of Leitneria fioridana Chapman, the single living representative of the order Leitneriales and Leitneria eocenica (Berry) Brown, presumbaly a related fossil species. In addition to the type material, newly collected fossil specimens were investigated from clay pits in the Middle Eocene, Claiborne Formation, of western Tennessee and Kentucky. Foliate stipules attached to the petioles of several specimens suggest the assignment of this fossil leaf type to the genus Leitneria is incorrect. The nature of the gross morphology, fine venation and cuticular features confirms the misidentification. Previously, various specimens of this fossil leaf type have been placed in eight species of seven genera in seven families of six angiosperm orders, none of which are correct systematically. The gross morphology, venation and cuticular characters of the fossil leaf are distributed among a few extant South American genera of arborescent Rubiaceae. The fossil is an extinct rubiaceous leaf type which cannot be placed within a single modern subfamily, tribe or genus of the family. The organ genus, Paleorubiaceophyllum is proposed for these leaves. Three varieties of a single fossil species, P. eocenicum, are recognized. One variety with epidermal cells nearly twice the size of the others may represent a polyploid population.     

中国水青冈属 （壳斗科） 叶结构及分类学意义

叶结构对壳斗科(Fagaceae)现存植物和化石的鉴定具有重要意义。通过对水青冈属5种植物叶结构特征进行细致的研究,结果发现水青冈属植物叶脉有羽状弓形脉、羽状半达缘脉两种类型;三级脉有波状对生贯穿、互生贯穿及混合贯穿三种类型;小脉缺失、简单无分支或一次分支;脉间区发育良好,网眼有三边形、四边形和五边形三种类型,排列规则;具齿种类叶齿由齿主脉和齿侧脉构成,齿侧脉环状。研究结果表明水青冈属二级脉与更高级脉序形成的结构稳定且存在种间差异,具重要分类学价值。基于水青冈属叶结构特征观察结果,本次研究编制了水青冈属植物的分种检索表;参照已有研究结果并结合重要外部形态学特征,编制了壳斗科相关类群分属检索表。     

中国水青冈属（壳斗科）叶结构及分类学意义

叶结构对壳斗科（Fagaeeae）现存植物和化石的鉴定具有重要意义。通过对水青冈属5种植物叶结构特征进行细致的研究,结果发现水青冈属植物叶脉有羽状弓形脉、羽状半达缘脉两种类型;三级脉有波状对生贯穿、互生贯穿及混合贯穿三种类型：小脉缺失、简单无分支或一次分支：脉间区发育良好,网眼有三边形、四边形和五边形三种类型,排列规则;具齿种类叶齿由齿主脉和齿侧脉构成,齿侧脉环状。研究结果表明水青冈属二级脉与更高级脉序形成的结构稳定且存在种问差异．具重要分类学价值。基于水青冈属叶结构特征观察结果,本次研究编制了水青冈属植物的分种检索表：参照已有研究结果并结合重要外部形态学特征,编制了壳斗科相关类群分属检索表。     

Evolutionary trends in leaf morphology and biogeography of Altingiaceae based on fossil evidence

The extant woody family Altingiaceae, consisting of only one genus Liquidambar L. with ca. 15 species, demonstrates a typical disjunctive distribution among East Asia, North America, and the Mediterranean. However, the fossil record throughout the Cenozoic indicates that Altingiaceae was once widespread in the Northern Hemisphere. After studying the abundant Altingiaceae fossil leaf collections, we revised the easily-confused fossil leaves and corrected the misidentifications. Consequently, we proposed an evolutionary history of Altingiaceae leaf morphology in consulting the modern leaf characteristics. It is revealed that the trilobated leaf morphology is the ancestral character state, whereas both the pentalobated and the undivided, pinnate-veined lineages evolved separately. The latter diverged from the trilobated ancestor in South China in Eocene. The lobed and undivided lineages represent the deciduous and evergreen, respectively. An extensive fossil database of Altingiaceae was built to reconstruct its biogeographical history. We reconfirmed that Altingiaceae developed into a temperate and a subtropical-tropical patterns and migrated across both the Bering and North Atlantic land bridges since Cretaceous, independently. It was widespread in the early Neogene of North America and Eurasia, and became extinct in the high latitude triggered by the global cooling and aridification. The modern disjunctive distribution was finally formed, with southeast Asia as its modern diversity center. This study provides new fossil evidence for understanding the morphology and biogeography of the family Altingiaceae.     

Palaeopalynological Evidence of Phylogeny in Hamamelidaceae

This paper deals with evolution, classification and pollen morphology of the Hamamelidaceae, an important family in phylogeny of angiosperms. I. Pollen morphology and systematics of modern Hamamelidaceae. The pollen morphology of the family may be divided into the following four types: (1) Tricolpate: Hamamelis, Loropetalum, Mytilaria, Corylopsis, Sysopsis, and Distylum etc.; (2) Tricolpate with operculum: Disanthus; (3) Tricolporate: Rhodoleia; (4) Pantoporate: Liquidambar. The tricolpate pollen of the Hamamelidaceae is a primitive type in angiosperms, but the most ancient type is monocolpate pollen. Therefore, the family might have evolved from the Magnoliaceae of the monocolpate pollen. The pantoporate pollen is an evolutionary type in the family. It might have evolved from the tricolpate pollen. II.The fossil pollen of the Hamamelidaceae 1 .General introduction of the fossil pollen of the family Hamamelidaceae The most’ancient fossil pollen belonging to the family was found in the middle-late Early Cretaceous. Palynologists call the fossil pollen of the Hamamelidaceae Retitricolpites, which consists of three genera: Hamamelis L.,Corylopsis Sieb. et Zucc and Fothergilla Murr. Liquidambar is of an advanced type in the fossil pollen of the Hamamelidaceae. It was found in the period from the Palaeogene to the Neogene in China. 2. The geological history of the Hamamelidaceae may be divided into the following four stages: (A) The Early Cretaceous stage or origination stage. The family may be evolved from Magnoliales in the middle-late Early Cretaceous. (B)the Late Cretaceous stage or formation stage. The family is much developed in the period. (C) The Tertiary stage or development stage. The family was a much developed one among angiosperms. (D)The Neogene to modern stage or perfection stage. The evolutionary type, the Liquidambar type of the Hamamelidaceae, was much developed in the Neogene. III. The palaeopalynological evidence of evolution of the Hamamelidaceae The earliest fossil pollen of angiosperms was found in the Barremian (Early Cretaceous) in England, Israel, the United States of America etc., and was named as Clavatipollenites by Couper (1953). In recent years, Clavatipollenites was also found in the middle-late Early Cretaceous in Nei Monggol and Jiangxi Province of China. We also found Retitricolpites in the middle-late Early Cretaceous in Nei Monggol and Jiangxi Province. Retitricolpites, belonging to the Hamamelidaceae, is a primitive type among angiosperms, but it is younger than Clavatipollenites. Therefore, the pollen of Hamamelidaceae may have evoloved fromClavatipollenites, which may have evoloved in turn from that of Magnoliales.     

Study on the Pollen Morphology of the Chinese Family Oleaceae

This paper deals with the pollen grains of 11 genera, 22 species in Chinese Oleaceae. A comparative study on the pollen grains was carried out by means of scanning electron microscope and light microscope. The pollen grains of the family Oleaceae are almost spheroidal, oblate and prolate, in polar view tlie majority of the pollen grains are tri-lobulate-circular, the minority are tetra-lobulate-circular and dilobulate-circular. Pollen size: (15-65) × (12- 60)μ, 3-colporate and 3-colpate the minority of the pollen grains 4-colpate and 2- colpate colpus usually distinct and the en doaperature vague. The exine oonsists of two layers, the sexine thicker than the nexine, with big reticulum or fine reticulum, the majority of the reticulum are very distinct. On the basis of the pollen size and exine ornamentation, the pollen grains are divided into following two main types: (1) The larger pellen grains and the exine with big reticulum are found in the genera: Jasminum, Nyctanthes, Ligustrum, and Syringa. (2) The smaller pollen grains and the exine with finer reticulum are found in the genera: Osmanthus, Olea, Chionanthus, Fraxinus, Forsythia, Fontanesia and Linociera. In view of the features of pollen morphology, this family is much similar to the family Itamamelidaeeae. For example, the first pollen type resembles the genus Coryiopsis of the family Hamamelidaceae, but there are some differences between them, the former with a bigger reticulate exine and without any colpal membrane, the latter with a finer reticulate apocolpium and eolpate membrane. The second pollen type is much similar to that of the genera Hamamelis and Loropetalum of family Hamamelidaceae.     

绣球亚科的脉序研究

本文对绣球亚科全部９个属中选取４５个种或变种作了叶脉序的研究。绣球亚科除黄山梅属外,大体呈曲行羽状脉。叉叶蓝属,蛛网萼属和草绣球属同具真曲行羽状脉和相似的高级脉序;赤壁草属和冠盖藤属表现出明显的环结曲行羽状脉式样;钻地风属多呈现分支曲行羽状脉式样;常山属和绣球属包含多种过渡类型,与其它属密切相连。黄山梅属脉序为独特的羽状达缘型式样,明显表现出向掌状脉的过渡,与其它属不同。脉序研究支持Ｔａｋｈｔａｊａｎ系统把黄山梅属提升为亚科的处理,同时又表明从脉序性状来看,绣球亚科各属之间性状彼此重叠,没有十分明确的界限。     

Approaches to the identification of angiosperm leaf remains

During the past 125 years the history of early angiosperms, interpreted through the fossil leaf record has been largely an exercise in paleofloristic studies, ignoring evolution. Imprecise identifications of ancient leaves “matched” to extant genera and families have been used as the basis for reconstructions of paleocommunities and paleoclimates. However, as the result of careful morphological studies of leaf form, venation and cuticular features new insights into the evolution of angiosperms are now available. In this paper considerations are given to the usefulness and shortcomings of leaf form, venation and cuticular analysis as diagnostic tools of plant identification. Many techniques for the study of the morphology of modern and fossil leaves are included in this paper as well as tables outlining features of leaf venation and the epidermis. Careful morphological studies of leaf form (such as the venation and epidermal characters emphasized in this paper) will provide better understanding of the relationships of living angiosperms and transform the fossil leaf record into useful data that can be used to study the evolution of the angiosperms.     

贵州小檗属植物(小檗科)叶脉序研究

采用制作叶脉标本和透明叶标本的方法,对贵州产28种2变种小檗属植物叶脉特征进行比较研究。结果表明:贵州小檗属植物的脉序类型有5种:半达缘羽状脉、花环状半达缘羽状脉、简单弓形羽状脉、花环状弓形羽状脉和混合型。叶脉分支一般有五级:1一级脉构架均为羽状脉,粗度有很粗、粗、中等粗细和纤细四种类型,分支方式包括单轴分支和合轴分支;2粗二级脉构架中有分支达缘或分支均不达缘,与中脉夹角变化各异,内二级脉存在或缺失,细二级脉半达缘、真曲行或简单弓形,间二级脉类型复杂多变但频度种间有差异;3三级脉贯串型、结网型或分支型;4四、五级脉网状或自由分支且常混合在一起。脉间区从发育差到良好,小脉从不分支到不均等分支等各种类型均有,叶缘末级脉缺失、不完整、钉状和环状。大部分种类叶缘具齿,每1cm齿数目和齿内腺点的特性等特征在不同种类间有区别,具有鉴定价值,但齿其它特征复杂多变或种间区别较小,同时齿内脉性状也不稳定。此外,齿的有无会对脉序类型产生影响。小檗属植物叶脉类型存在种间差异,具有重要的分类学价值,叶脉类型的变化和复杂程度显示了该属植物的进化特点;叶齿的有无和齿特征具有分类学和系统学意义。基于叶脉特征的研究结果并结合重要的外部形态学特征编制了贵州小檗属植物的分种检索表。研究结果可为小檗属植物分类寻找新的依据并探讨其系统学意义。     

国产五味子科五种植物叶片脉序研究

首次报道了国产五味子科５种植物的叶脉特征,对科、属、种的特征作了描述,编排有分种检索表．通过与八角科叶脉的比较,支持建立五味子科与八角科的观点,认为五味子属的系统位置在南五味子属之后,并讨论了八角目的演化趋势     

Evolutionary relationships of wing venation and wing size and shape in Aphidiinae (Hymenoptera: Braconidae)

We explored evolutionary changes in wing venation and wing size and shape in Aphidiinae, one of the well-known groups of parasitic wasps from the family Braconidae. Forewings of 53 species from 12 genera were examined, for which a molecular phylogeny was constructed on the basis of the mitochondrial barcoding gene COI. By covering all types of wing venation within the subfamily Aphidiinae and by using landmark-based geometric morphometrics and phylogenetic comparative methods, we tested whether evolutionary changes in wing shape correlate to the changes in wing venation and if both changes relate to wing size. The relationship between wing morphology and host specificity has been also investigated. We found that six types of wing venation, with different degree of vein reduction, could be recognized. Wing venation type is largely genus specific, except in the case of maximal reduction of wing venation which could be found across examined Aphidiinae taxa. The reconstruction of evolutionary changes in wing venation indicates that evolutionary changes in wing shape are related to the changes in wing size, indicating that miniaturization play a role in evolution of wing morphology while host specialization does not affect the wing shape within the subfamily Aphidiinae.     

Comparative infructescence morphology in Liquidambar (Altingiaceae) and its evolutionary significance

The sweet gum genus Liquidambar (Altingiaceae) has two species in eastern Asia, one in eastern North America, and one in western Asia. Mature infructescences are studied to provide anatomical, morphological, and micromorphological details, some of which are newly recognized. Homology is suggested between extrafloral spinose processes of L. formosana and L. acalycina, braid-like ornamentation of L. styraciflua, and broad intercarpellate areas of L. orientalis. Morphology, position, number, and the presence of similar structures in the closely related Hamamelidaceae s.s. support their derivation from sterile flowers. Morphological cladistic analysis using 43 characters supports the monophyly of Liquidambar with Altingia as its sister. The matK analysis contrastingly places Altingia sister to the L. acalycina-L. formosana clade, rendering Liquidambar paraphyletic. Discordance between morphological and matK data sets may result from both different rates of morphological evolution and convergence. Several similarities between Altingia and L. acalycina are symplesiomorphic in the morphological cladistic analysis. Microaltingia apocarpela, from the Cretaceous of eastern North America, documents the earliest known fossil divergence within Altingiaceae. The Miocene Liquidambar changii of western North America is sister to a clade of extant Liquidambar species. Consideration of this fossil evidence reveals complex intercontinental biogeographic disjunctions in Altingiaceae.     

云南元谋盆地上新世甘棠组植物和孢粉组合及其古气候意义

云南元谋盆地湾堡甘棠组植物群的叶化石和孢粉化石合计107种类型,分属86属,47科。植物叶化石包括18科,24属,35种。除一种裸子植物外,其它均为被子植物。被子植物中,榆科、桦木科、豆科无论属种或者化石数量都是最多;杨柳科、槭科、蔷薇科次之;壳斗科、樟科、杨梅科、鼠李科、忍冬科、胡颓子科、杜鹃科、香蒲料、禾本科均有代表。甘棠组的孢粉植物群也相当丰富,合计97个类型,分属72属,44科。以松科、榆科、禾本科及蕨类植物的水龙骨科最为丰富,胡桃科、壳斗科、金缕梅科及蕨类植物的凤尾蕨属也很常见。被子植物花粉占孢粉总数的50%--60%,以禾本科和榆属花粉含量最高,多在10%以上。裸子植物绝大部分为松科花粉,占孢粉总数的20%-30%。孢子以水龙骨科和凤尾蕨属为主,二者各占孢粉总数的5%-10%。发现于元谋盆地湾堡甘棠组的植物叶化石以及孢子花粉组合在成分上都是混合的类群。组合中既有相当多的湿润亚热带常绿阔叶林成分,也有耐干旱的胡颓子、杨梅、旱蕨等灌木、小乔木或草本分子,同时还有含量很高的、在半干旱环境下也能生存的禾本科、榆科花粉。据此推测甘棠组的植物群和孢粉组合反映了上新世时元谋地区的植被已经分化,盆地的周围山地生长有松科、壳斗科、樟科、胡桃科、金缕梅科为主的常绿和落叶阔叶树木或林块,可能有少许杜鹃科小乔木混杂其中,属于地带性植被。而在盆地内则是以禾本科、蔷薇科等为主,杂以大戟科、豆科、忍冬科、杨梅科等灌木或草本植物以及榆科、桦木科等树木组成的稀树灌丛草原型植被。盆地内的植被所反映的气候和周边地区相比,显得明显干旱。因此推测元谋盆地在2-3百万年前的中晚上新世已经发育成为金沙江流域的干热河谷盆地之一。     

Variation and Evolution of Leaf Trichomes in the Chinese Hamamelidaceae

Leaves of 25 species which cover 13 genera of the Chinese Hamamelidaceae (sensu lato ) were examined by light microscope (LM) and scanning electron microscope (SEM) to reveal the nature and variation of trichomes. The trichomes showed greater diversity under SEM than under LM and naked eyes. Based on Theobald’s scheme, they can be divided into four types: 1. Simple trichomes: Unbranched, curved or straight (Altingia, liquidambar, Semiliquidambar; 2. 2- 4 armed trichomes: Two to four branched (Corylopsis, Loropetalum, sinowilsonia); 3. Stellate trichomes: With more than five branches. They may be tufted (Forthunearia, Loropetalum, sinowilsonia, Hamamelis, Distylium) or storied (Eustigma); 4. Scales: Peltate and flattened. In the genus Rhodoleia, the scales are totally composed of small boat-shaped ones, whereas in the genus Sycopsis they are rotately branched on the verge but unbranched and flattened in the middle. The distribution of trichome types is of grest significance in hamamelidaceous phylogeny. The simple trichomes mainly exist in Liquidambaroideae and Exbucklandioideae, the stellate and 2-4 armed trichomes occur in Hamamelidoideae, and the scales are confined to Sycopsis (Hamamelidoideae) and Rhodoleia (Rhodoleioideae). From this fact, the authors consider that there are two evolutionary lines in the family, i. e. the Disanthoideae- Exbucklandioideae- Liquidambaroideae line and the Rhodoleioideae-Hamamelidoideae line though some subfamilies are isolated. Within Hamamelidoideae, the trichome types also have taxonomic significance. Corylopsis is a primitive group, whereas Eustigma, Distylium and Sycopsis are respectively on the top of evolutionary branches and the other genera are transitional groups. These genera might be separated as tribes, Corylopsideae, Eustigmateae, Distylieae, Sycopsideaeand Hamamelideae. The relationships among these tribes are given in Fig. l.