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1.
Twenty-two chromosome counts of 19 taxa (21 populations) in the tribe Anthemideae and one member (one population) of the tribe Inuleae of the family Asteraceae are reported. The Anthemideae studied belong to the subtribes Artemisiinae (14 Artemisia taxa, and one species each of the genera Dendranthema , Filifolium and Neopallasia ) and Tanacetinae (one species each of the genera Lepidolopha and Tanacetopsis ). From the Inuleae, we studied one Inula species. Five counts are new reports (including two at generic level), six are not consistent with previous counts and the remainder are confirmations of very limited (one to four records) previous data. Most of populations of Anthemideae studied have the basic chromosome number x  = 9, with ploidy levels ranging from 2 x to 10 x . Dysploidy is also present, with two x  = 8 diploid taxa. The species of Inuleae studied is a diploid with x  = 10, also indicating dysploidy, other members of the same genus Inula having basic numbers of x  = 9 or 8.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 77–85.  相似文献   

2.
The phylogenetic relationships between the tribes Inuleae sensu stricto and Plucheeae are investigated by analysis of sequence data from the cpDNA gene ndhF. The delimitation between the two tribes is elucidated, and the systematic positions of a number of genera associated with these groups, i.e. genera with either aberrant morphological characters or a debated systematic position, are clarified. Together, the Inuleae and Plucheeae form a monophyletic group in which the majority of genera of Inuleae s.str. form one clade, and all the taxa from the Plucheeae together with the genera Antiphiona, Calostephane, Geigeria, Ondetia, Pechuel-loeschea, Pegolettia, and Iphionopsis from Inuleae s.str. form another. Members of the Plucheeae are nested with genera of the Inuleae s.str., and support for the Plucheeae clade is weak. Consequently, the latter cannot be maintained and the two groups are treated as one tribe, Inuleae, with the two subtribes Inulinae and Plucheinae. The genera Asteriscus, Chrysophthalmum, Inula, Laggera, Pentanema, Pluchea, and Pulicaria are demonstrated to be non-monophyletic. Cratystylis and Iphionopsis are found to belong to the same clade as the taxa of the former Plucheeae. Caesulia is shown to be a close relative of Duhaldea and Blumea of the Inuleae-Inulinae. The genera Callilepis and Zoutpansbergia belong to the major clade of the family that includes the tribes Heliantheae sensu lato and Inuleae (incl. Plucheeae), but their exact position remains unresolved. The genus Gymnarrhena is not part of the Inuleae, but is either part of the unresolved basal complex of the paraphyletic Cichorioideae, or sister to the entire Asteroideae.  相似文献   

3.
The tribe Inuleae (Asteraceae) has 10 species endemic to the Macaronesian islands, including the three endemic genera Allagopappus, Schizogyne, and Vierea. Phylogenetic analyses of DNA sequence data from the internal transcribed spacers (ITS) of the nuclear ribosomal DNA of 47 taxa were performed using all Macaronesian endemics and representative species from 21 of the 36 genera of the Inuleae. The resulting ITS phylogeny reveals that Allagopappus is sister to a large clade that contains all genera with a predominantly Mediterranean distribution. This finding suggests that Allagopappus may represent an ancient lineage that found refuge in the Canary Islands following the major climatic and/or geologic changes in the Mediterranean basin after the Tertiary. The Macaronesian endemic genus Schizogyne is sister to Limbarda from the Mediterranean. The third Macaronesian endemic genus, Vierea, is sister to Perralderia, which is restricted to Morocco and Algeria. Pulicaria canariensis is sister to P. mauritanica, a species endemic to Morocco and Algeria. In contrast, P. diffusa from the Cape Verde Islands is sister to a broadly distributed species, P. crispa, that occurs from North Africa to the Arabian peninsula. Based on the ITS data, the genera Blumea, Inula, and Pulicaria are not monophyletic. The ITS trees suggested that Blumea mollis belongs to the tribe Plucheeae, a finding that is congruent with recent morphological evidence. A possible southern African origin for the core of the Laurasian taxa of the Inuleae is also suggested.  相似文献   

4.
Leaf anatomy is compared for all species of Raoulia. The species are tabulated according to their lamina structure. Noteworthy anatomical features are lamina type and grade of differentiation, stomatal position, epidermal and cuticle thickness, shape of mesophyll cells, presence or absence of central clear cells, sclerenchyma caps, abaxial collenchyma and protruding midrib. It is shown that leaf anatomy data provide characters which are taxonomically useful in Raoulia. The main subgenera are supported except that the leaf anatomy of R. haastii is anomalous and that of R. youngii is typical of R. subg. Raoulia rather than R. subg. Psychrophyton. The leaf anatomy of R. petriensis is unique in the genus.  相似文献   

5.
6.
Achene anatomy and stomatal characteristics of eighteen Crepis taxa from Turkey are here described for the first time. In all taxa examined the pericarp is composed of several layers of sclerenchymatous and parenchymatous cells. As for the achene, differences among taxa mainly concern the pericarp structure and its thickness and width. Stomata are present on both surface of the leaf in all studied taxa and all taxa have anomocytic type stomata. However, the dimensions (length and width) and density of the stomata differ significantly among the studied taxa. In addition, the dimensions of stomata are negatively correlated with stomata density. It is concluded that achene anatomy and stomatal characteristics are useful for delimitation of Crepis taxa and a key to taxa based on these characters is provided. However, based on achene anatomy and stomatal characteristics, we found no argument for an exclusion of the Lagoseris group from Crepis as has previously been proposed.  相似文献   

7.
We present a synopsis of the genus Geigeria (Inuleae, Asteraceae). Particular attention is paid to the taxonomic characterization and phylogenetic relationships of the genus, to possible supraspecific groupings, and to the delimitation of taxa, especially at the infraspecific level. Until recently 25 species, 20 subspecies, and 7 varieties have been recognized. In this study we recognize only 20 species, 12 subspecies, and 7 varieties. We describe a new subspecies and variety, and propose 5 new nomenclatural combinations.  相似文献   

8.
TRIBAL INTERRELATIONSHIPS OF THE ASTERACEAE   总被引:3,自引:0,他引:3  
Abstract— A cladistic analysis involving 27 tribes and subtribes of Asteraceae and 81 characters is presented. The terminal taxa are mainly those of present tribal classification, though some apparently poly- and paraphyletic tribes, notably the Mutisieae and the Inuleae, have been represented by sub-tribal taxa. Characters are assembled from all available sources. Corolla types, styles and stamens have provided many characters. The Lobeliaceae are used as an outgroup and are considered as the most probable sister group of the Asteraceae. There is a basal dichotomy in the family, the Mutisieae-Barnadesiinae being the monophyletic sister group of the remaining major, also monophyletic part of the family. The recent family division into two subfamilies about equal in size, the Cichorioideae and the Asteroideae, neither represents a basal dichotomy nor a sister group relationship within the Asteraceae. The Asteroideae are monophyletic and have their sister group within the paraphyletic Cichorioideae. Interrelationships among the cichorioid tribes are still unclear. The Lactuceae, Eremothamneae, Vernonieae and Liabeae may be one monophyletic group, and the Arctoteae, Carlineae, Echinopsideae and Cardueae another. The Mutisieae are a paraphyletic grade at the base of the family. Within the subfamily Asteroideae tribal interrelationships are also rather unclear. The Anthemideae and the Heliantheae sensu lato (including the Helenieae, Tageteae, Coreopsideae and all helenioid/helianthoid representatives sometimes placed in the Senecioneae) may be sister groups. The Heliantheae appear to be monophyletic and there is little support for the hypothesis that other tribes are derived from or have their sister group within the Heliantheae. The Astereae and the Eupatorieae may be sister groups, though a closer relationship between the Eupatorieae and the Heliantheae is possible. The Inuleae are a paraphyletic grade group at the base of the subfamily Asteroideae in the same way as the Mutiseae are a grade group at the base of the family.  相似文献   

9.
Three members of the tribe Gnaphalieae and six members of the tribe Inuleae (Asteraceae) were analyzed for their exudate flavonoids. Whereas some species exhibit rather trivial flavonoids, others produce rare compounds. Spectral data of rare flavonoids are reported and their structural identification is discussed. 6-Oxygenation of flavonols is a common feature of two Inula species and Pulicaria sicula. By contrast, flavonoids with 8-oxygenation, but lacking 6-oxygenation, are common in two out of three Gnaphalieae species examined. In addition, B-ring deoxyflavonoids are abundantly present in the leaf exudates of Helichrysum italicum (Gnaphalieae). These distinctive features of the two Asteraceae tribes are in agreement with previous flavonoid surveys of these and related taxa.  相似文献   

10.
Among the subgenera of the genus Carex, the subgenus Indocarex has been seldom studied in any respects, Its systematic position and its subdivision are still disputable. Leaf anatomy of 14 species in the subgenus lndocarex from China was studied. The anatomical characters are proved to be systematically valuable. (1) Characters of lamina transverse section: All leaves of these 14 species are dorsiventral. The outline mostly V-shaped, occasionally flat or nearly flat, with adaxial lateral rib in each half of lamina and some of them flanged. The cells of adaxial surface larger than those of abaxial surface, and the epidermal cells over veins usually smaller than others. Air-cavities between vascular bundles are well developed, and bulliform cells also well developed in most taxa. The vascular bundles are collaterai, bundle sheaths double-layered, and the outer sheath parenchymatous and the inner sheath fibrous. (2) Characters of lamina epidermis: The shape of the cell on both surfaces is generally rectangular, and the anticlinal wall of epidermal cell sinuous; stomata is paracytic, elliptic to oblong, rarely sub-circular; prickles occur on adaxial surfaces of certain species; papillae are only obvious on abaxial surface of C. moupinensis Franch. The characters of transverse section and epidermis of leaf blades of these 14 species differ from each other to certain degree, and closely related species are similar in anatomical characters. The anatomical characters of lamina are of value for classification at specific and sectional level of the subgenus Indocarex. Despite of the variation of these characters among species, a certain num ber of characters appears to be shared by the members of the subgenus, and some of the common characters are primitive. In addition, some gross morphological characters are common and primitive also. Therefore, the subgenus Indocarex may be primitive in the genus Carex. The anatomical and morphological characters of C. scaposa C. B. Clakre and C. densifimbriata Tang et Wang ex S. Y. Liang are distinct. The two species and their allies should be treated as section instead of subsection. The three species in the sectionPolystachyae share some anatomical characters and comprise a coherent group.  相似文献   

11.
苔草属复序苔草亚属十四种植物叶片的解剖学研究   总被引:2,自引:0,他引:2  
选择中国复序苔草亚属6组4亚组的代表植物14种,进行了叶片解剖学研究,观察了其横切面 和表皮特征,证明上述特征在各类群之间存在差异,具有一定的系统学意义。这14种植物叶片的横切 面和表皮都具有一些原始的性状,表明复序苔草亚属中的植物可能在苔草属中是较原始的。在所观察 的植物中,Sect.Polystachyae植物叶片解剖学特征比较一致,说明此组的建立比较合理;而Sect.Indicae 组已有明显分化,尤其是Carex scaposa C.B.Clarke和C.densifimbriata Tang et S.Y.Liang 与其它植物明显不同,而且其外部形态特征在复序苔草亚属中也比较独特,因此赞成将它们及其近缘类群做为一个组而非亚组。  相似文献   

12.
The anatomy of the palatoquadrate ossifications of the Lower Triassic archosauromorph Proterosuchus fergusi from South Africa is described. It consists of two ossifications, the epipterygoid and the quadrate, which were joined by cartilage in life. The margins of the cartilage are clearly indicated by ridges and grooves on the dorsal surface of the pterygoid. The epipterygoid ossification consists of two structures: the anteroposteriorly expanded basal portion and, dorsally from it, an extending, slender, ascending process. From the anterior margin of the basal portion of the epipterygoid, a plate‐like structure, herein called the lamina epipterygoidea anteromedialis, extends anteromedially to form the anterolateral wall of the cavum epiptericum. Comparisons with the similarly constructed embryonal and adult epipterygoid components of Sphenodon punctatus show that the anteromedial lamina of the epipterygoid of P. fergusi is an additional component of the epipterygoid of this species and that this lamina is absent in the former species. However, a structure in a topologically similar position to the anteromedial lamina of the epipterygoid of P. fergusi is present in the palatoquadrate of Alligator mississippiensis. In the latter species, the structure is called the lamina palatoquadrati anterior; it ossifies in membrane and forms the dorsolateral cover of the huge trigeminal ganglion. It is hypothesized here that the anteromedial lamina of the epipterygoid of P. fergusi and the anterior lamina of the palatoquadrate of A. mississippiensis are most probably homologous structures and are present in both the basal and one of the crown taxa of the archosauromorph clade, respectively.  相似文献   

13.
14.
Leaf anatomy of six genera was investigated. The petiole of Brasenia schreberi possesses a pair of bundles, the other five possess closed, scattered vascular bundles, resembling those of the Monocotyledons. True vessels are absent. Air passages are present in the ground tissue of the petiole except for Nuphar pumilum. Leaves are all dorsiventral. Stomatal apparatuses of the Ranunculaceous type are generally confined to the upper surface of the lamina, but fewer stomata are found on the lower surface of the lamina of Nelumbo nucifera. The stomatal apparatuses of Nelumbo nucifera are of the Haplocheilic type in development, but of the Ranunculaceous type at maturity. Hydathodes and sclerenchymatous idioblasts are present only in Nelumbo nucifera. Glandular hairs and hydropotens occur on the lower surface of the lamina in all the investigated species except Nelumbo nucifera. Astrosclereids are present in all the taxa except Brasenia schreberi and Nelumbo nucifera. According to observations we consider that the genus Brasenia is a primitive one in Nymphaeaceae and it has a close phylogenetic relationship with Cabomba. They may be treated as an independent family, Cabombaceae, which is better included in the order Nymphaeales. Nymphaea, Nuphar, Euryale and Victoria are closely related to one another and should be retained in the family Nymphaeaceae. Nelumbo shows, specialized features distinct from those of the rest of the Nymphaeaceae. It should be segregatednot only as a distinct family but also as a distinct order, Nelumboales.  相似文献   

15.
运用比较形态学和比较解剖学方法,使用扫描电镜和光学显微镜对紫花苜蓿复合体(Medicago sativa complex)6个分类群的叶片形态特征和叶片解剖结构进行了观察和比较,并以15个叶片表征形态性状为基础,采用聚类分析法(UPGMA)和主成分分析方法(PCA)对6个分类群进行了数量分类研究.观察结果表明:各分类群叶片的上、下表皮多为不规则形细胞;垂周壁呈深浅不一的波状;气孔器为不规则型,具有蜡质气孔盖,气孔密度有一定差异.6个分类群的叶片均为薄纸质型,厚度130~170 μm,表皮细胞切面近圆形或近长方形;栅栏组织细胞1~2层,厚度41~68 μm,细胞排列紧密;海绵组织厚度32~75 μm,细胞排列疏松;不同分类群叶片的组织疏松度和组织紧缩度有一定的差异,大花苜蓿(M. trautvetterii Sumnev. )叶片的组织疏松度最高,紫花苜蓿叶片的组织紧缩度最高.UPGMA结果显示:在结合线1.53处可将6个分类群划分为2支,其中,黄花苜蓿(M. falcata L. )独立为一支,其余5个分类群聚成另一支;在结合线1.18处,第2支又被分成2个亚支,其中一个亚支包含紫花苜蓿和天山苜蓿(M. tianschanica Vassilcz. ),另一个亚支则包含西锡金苜蓿(M. schischkinii Sumnev. )、座垫苜蓿(M. rivularis Vassilcz. )和大花苜蓿.PCA结果表明:对紫花苜蓿复合体而言,叶片表皮细胞形状、垂周壁式样、轴性分化特征、组织疏松度和气孔密度等特征具有较好的分类价值;基于主成分分析的Q分布图与聚类分析结果也具有较高的一致性.根据本研究结果及前人的研究结果,认为国产的紫花苜蓿复合体应包含3个分类群,即紫花苜蓿、黄花苜蓿及多变苜蓿(M. varia Martyn).此外,西锡金苜蓿、座垫苜蓿、天山苜蓿和大花苜蓿等杂交后代分类群的性状分化不稳定,应属于多变苜蓿的同种异名植物.  相似文献   

16.
To better understand the relationships within the Asteroideae and Inuleae, the structure of the pollen exine was investigated in seven genera and nine species of the subtribe Inulinae using LM, TEM and SEM. All taxa have a senecioid pattern of exine. The tectal complex consists of three main layers that differ in thickness and morphology: a tectum, a columellar layer, and a layer consisting of the basal region of the columellae. The absence or the vestigial condition of the foramina is considered as a plesiomorphy within the Asteroideae. All taxa have a complex apertural system that consists of an ecto-, a meso-, and an endoaperture. These apertures intersect respectively the tectal complex, the foot layer and the upper part of the endexine, and the inner layer of the endexine. A continuous transition among the different species of Inulinae was found for all the quantitative characters examined. This relative homogeneity of the pollen morphological characters enhances the naturality of the subtribe Inulinae.  相似文献   

17.
A comprehensive study of the nodal and leaf anatomy of Bonnetiaceae was completed in order to provide evidence for evaluation in relation to systematics. Nodal anatomy is trilacunar, three-trace or unilacunar, one-trace. Basic leaf anatomical features of the family include: complete or incomplete medullated vascular cylinder in petiole; paracytic mature stomata with encircling ridges; large mucilaginous cells in the adaxial surface of mesophyll; periclinal divisions in upper surface layers; and discrete patches of phloem within the vascular bundles. Especially noteworthy is the presence in some genera of foliar vascular bundles enveloped by a sheath composed of two concentric regions, i.e., an inner region consisting of multiple layers of fibers and an outer specialized endodermis composed of thin-walled cells with Casparian strips. Leaves are variable with respect to lamina and cuticle thickness, relative amount and number of palisade and spongy layers, venation of lamina, and the presence or absence of sclereids and crystals in the mesophyll. A major feature in the evolution of Bonnetiaceae is development of a highly divergent, essentially parallel, leaf venation that is superficially similar to that of some monocotyledons and apparently unique among dicotyledons. Foliar anatomy provides important characters for the recognition of subgroups within Bonnetiaceae and is consistent with the segregation of Bonnetiaceae from Theaceae.  相似文献   

18.
In malacostracan crustaceans and insects three nested optic lobe neuropils are linked by two successive chiasmata that reverse and then reverse again horizontal rows of retinotopic columns. Entomostracan crustaceans possess but two retinotopic neuropils connected by uncrossed axons: a distal lamina and an inner plate-like neuropil, here termed the visual tectum that is contiguous with the protocerebrum. This account proposes an evolutionary trajectory that explains the origin of chiasmata from an ancestral taxon lacking chiasmata. A central argument employed is that the two optic lobe neuropils of entomostracans are homologous to the lamina and lobula plate of insects and malacostracans, all of which contain circuits for motion detection—an archaic attribute of visual systems. An ancestral duplication of a cell lineage originally providing the entomostracan lamina is proposed to have given rise to an outer and inner plexiform layer. It is suggested that a single evolutionary step resulted in the separation of these layers and, as a consequence, their developmental connection by a chiasma with the inner layer, the malacostracan-insect medulla, still retaining its uncrossed connections to the deep plate-like neuropil. It is postulated that duplication of cell lineages of the inner proliferation zone gave rise to a novel neuropil, the lobula. An explanation for the second chiasma is that it derives from uncrossed axons originally supplying the visual tectum that subsequently supply collaterals to the opposing surface of the newly evolved lobula. A cladistic analysis based on optic lobe anatomy of taxa possessing compound eyes supports a common ancestor of the entomostracans, malacostracan crustaceans, and insects.  相似文献   

19.
The microscopic anatomy and ultrastructure of the body cavity and adjacent organs in the sea spider Nymphon brevirostre Hodge, 1863 (Pycnogonida, Nymphonidae) were examined by transmission electron microscopy. The longitudinal septa subdividing the body cavity are described: (1) Dohrn’s horizontal septum, (2) lateral heart walls, and (3) paired ventral septa consisting of separate cellular bands. The body cavity is a hemocoel, it has no epithelial lining and is only bordered by a basal lamina. The epidermis, heart, and Dohrn’s septum are not separated from each other by basal laminae and may have a common origin. The cellular bands forming the longitudinal ventral septa are not covered with the basal lamina and presumably derive from cells belonging to the hemocoel. The roles of the morphological structures studied for the circulation of hemolymph are discussed. The gonad lies inside Dohrn’s septum, it is covered with its own basal lamina and surrounded by numerous lacunae of the hemocoel entering the septum. The gonad wall is formed with a single layer of epithelium. The same epithelial cells form the gonad stroma. The gonad cavity is not lined with the basal lamina; muscle cells are present in the gonad wall epithelium, thus rendering the lumen similar to a coelomic cavity. Freely circulating cells of two types are found in the hemocoel: small amebocytes containing electronic-dense granules that are similar to granulocytes of other arthropods, as well as hemocytes with large vacuoles of varying structure that are comparable with plasmatocytes; however some of these may be activated granulocytes.  相似文献   

20.
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