Phytoserological systematic survey of the caprifoliaceae

Although several investigators have presented data suggesting that the Caprifoliaceae is polyphyletic in origin, the family has been retained as a taxon in recent classifications. Serological analyses of the taxa included within the family have been undertaken to provide additional taxonomic data. Precipitin techniques of double diffusion (Ouchterlony) and nephelometry (Boyden Procedure) were used to analyse serological similarities of seed proteins from representatives of the family. Three distinct groupings were detected for the taxa included in the Caprifoliaceae. AlthoughViburnum exhibited greatest serological similarity withSambucus, Viburnum was quite distinct from all members of the family investigated.Sambucus also was somewhat distinct from the other genera and exhibited about as much serological correspondence withCornus of the Cornaceae as with any tested member of the Caprifoliaceae. The remaining species examined formed a very close serological grouping. These data can be interpreted as supporting either a monophyletic or polyphyletic origin of the family as presently composed, because of the different arrangements of the families Caprifoliaceae and Cornaceae in the various systems of classification.     

PHYLOGENY OF THE RUBIACEAE AND THE LOGANIACEAE: CONGRUENCE OR CONFLICT BETWEEN MORPHOLOGICAL AND MOLECULAR DATA?

Phylogenetic analyses of 33 genera of Rubiaceae were performed using morphological and a few chemical characters. Parsimony analysis based on 29 characters resulted in eight equally parsimonious trees, with a consistency index of 0.40 and a retention index of 0.69. These results were compared to a phylogenetic analysis of the same genera based on chloroplast DNA restriction site data. There are discrepancies between the two analyses, but if we consider groupings reflected in the present classification there is much congruency. With the exception of four genera, all the genera are positioned in the same group of taxa in the two analyses. Clades of taxa representing three of the four subfamilies (~the Antirheoideae, ~the Rubioideae, and the ~Ixoroideae) are monophyletic, while the fourth subfamily Cinchonoideae is shown to be paraphyletic. Both analyses support a widened tribe Chiococceae, including the former subtribe Portlandiinae (Condamineeae). Furthermore, in both analyses the tribe Hamelieae is placed outside the subfamily Rubioideae where it is now housed. In search for the most plausible sister group to the Rubiaceae, the genus Cinchona (Rubiaceae) was analyzed together with 13 genera of the Loganiaceae, Nerium (Apocynaceae), and Exacum (Gentianaceae). Cornus (Comaceae), Olea (Oleaceae), and these two genera together were used as outgroups. The analysis, including 25 characters, 16 taxa, and with Cornus and Olea together as an outgroup, resulted in four equally parsimonious trees, with a consistency index of 0.53 and a retention index of 0.62. The non-Loganiaceae taxa Cinchona (Rubiaceae), Nerium (Apocynaceae), and Exacum (Gentianaceae) were all found to have their closest relatives within the Loganiaceae indicating that the Loganiaceae are paraphyletic and ought to be reclassified. As a result of the morphological data the most plausible sister group to the Rubiaceae is the tribe Gelsemieae of the Loganiaceae.     

核酸碱基组分与毛霉目的分类

本文对毛霉目中6科16属40个种共60株真菌DNA的G+C含量与分布作了系统的研究。在提取DNA时选用了Storck等人在Marmur提取细菌DNA方法基础上发展起来的真菌DNA提取法,经过一些修改后成功地提取了毛霉目真菌的DNA。经该法提取的DNA片段长、纯度高,在热变性时DNA的增色效应一般都大于35%。各个种的GC含量大致有一固定值。根据所测毛霉目16属各属真菌的平均GC含量,可将它们分为明显的三组:Gongronella, Haplosporangium, Mortierella及Syncephalastrum为一组,GC含量最高为46.0-49.8%; Cunninghamella单独成一组,GC含量最低只有28.8%;其他各属包括Absidia, Mucor, Rhizopus等GC含量介乎这两组之间,分布于34.9-41.9%。这一次序除Helicostylum与Circinella的数值低于他人的报道外,其余和文献报道值一致。一般属内GC含量变化小于10%,种内变化小于2%。所测得的G+C mol%对分Syncephalastrum monosporum Zheng et al.和Mortierella ramanniana (Moeller) Linneman的合理归属提供了佐证。对某些所测结果与文献报道值有出入的原因作了讨论和分析。对采用Mandel等1970年建议的公式GC=(Tm 0.1×SSC/50.2)-0.990来计算GC含量的依据也作了讨论。     

Pollen Morphology of Caprifoliaceae from China and Its Taxonomic Signi-ficance

The pollen morphology of 54 samples representing 12 genera and 31 species was investigated with the aid of scanning electron microscope. Observed were pollen grains of Sambucus, Viburnum, Lonicera, Leycesteria, Heptacodium, Linnaea, Abelia, Dipelta, Kolkwitzia, Symphoricarpos, Triosteum, Weigela. Based on the shape, size, position and number of aperture, exine sculpture, three types are recognized: 1. Pollen grains subprolate, less frequently prolate, rather small, 3-colporate, exine reticulate, as in Sambucus, Viburnum. 2. Mostly spheroidal, subolate, bigger than the former, also 3-colporate, exine spinulose as in Lonicera, Leycesteria, Heptacodium, Triosteum, Linnaea, Abelia, Dipelta, Kolkwitzia, Symphoriocarpos, Weigela. 3. Spheriodal, more or less flattend, exine scabrous as in Abelia section Zabelia and Lonicera section Isoxylosteum. 1. The systematic position of Caprifoliaceae: It has been generally treated as a member of the order Rubiales together with Rubiaceae, Valeriaceae and Dipsacaceae on floral characters. In respect to serological character, it has a close relationship with Cornaceae, and was placed in Araliales. The above stated 2nd and 3rd types of pollen grains are similar to those of Patrinia (Valerianaceae), Scabiosa (Adoxaceae), Cornus (Cornaceae), and the pollen grains of the 1st type are similar to those of Styraceae, Genetianaceae and Araliaceae. Taking the information so far available into consideration, the authors agree to the Cronquists treatment retaining Caprifoliaceae in the order Dipsacales together with Adoxaceae, Valerianaceae and Dipsacaceae. 2. The division of tribes: Formerly Sambuceae included the genera Sambucus and Viburnum. Fritsch (1891) segregated Viburnum from Sambuceae and suggested a new tribe Viburneae including Triosteum. There is distinct difference in palynological features between these two genera. The exine sculpture of Viburnum is reticulate, but that of Triosteum is spinulose. It is reasonable to separate another new tribe, Triosteae, from Viburneae. 3. The pollen morphorlogy of several Chinese endemic genera, such as Heptacodium, Dipelta, Kolkwitzia resembles that of Lonicera, Leycesteria, Linnaea, Symphoricarpos, Abelia, Triosteum. This evidence supports the foregoing treatment including them in Caprifoliaceae. 4. Two different exine sculptures are shown in sections of the genera Abelia and Lonicera. In Abelia the exine of the section Euabelia is spinulose, but that of the section Zabelia is scabrous. Likewise, in Lonicera, the exine of the section Isoxylosteum is scabrous, while that of other sections such as Nintooa, Isika, Lonicera, subgenus Caprifolium, is spinulose. It shows that pollen morphology is one of diagnostic characters for section division.     

COLEOFASCICULUS GEN. NOV. (CYANOBACTERIA): MORPHOLOGICAL AND MOLECULAR CRITERIA FOR REVISION OF THE GENUS MICROCOLEUS GOMONT1

Species currently classified within the cyanobacterial genus Microcoleus were determined to fall into two distinct clades in a 16S rDNA phylogeny, one containing taxa within the Oscillatoriaceae, the other containing taxa within the Phormidiaceae. The two lineages were confirmed in an analysis of the 16S–23S internal transcribed spacer (ITS) region sequences and secondary structures. The type species for Microcoleus is M. vaginatus Gomont, and this taxon belongs in the Oscillatoriaceae. Consequently, Microcoleus taxa in the Phormidiaceae must be placed in separate genera, and we propose the new genus Coleofasciculus to contain marine taxa currently placed in Microcoleus. The type species for Coleofasciculus is the well‐studied and widespread marine mat‐forming species Microcoleus chthonoplastes (Mert.) Zanardini ex Gomont. Other characters separating the two families include type of cell division and thylakoid structure.     

COMPARATIVE ANATOMY OF CHAROPHYTA: II. THE AXIAL NODAL COMPLEX—AN APPROACH TO THE TAXONOMY OF LAMPROTHAMNIUM12

The present investigation on the axial nodes of 32 taxa belonging to the genera Chara, Lamprothamnium, Nitellopsis, Nitella and Tolypella confirms previous reports that within a given taxonomic group the structure of the main axial nodal complex is highly consistent. Besides the genera Nitella and Tolypella of the tribe Nitelleae, Lamprothamnium of the tribe Chareae is the only genus in which the central cells of the main axial nodal complex subdivide. This anatomical feature of the main axial nodal complex thus clearly separates the genus Lamprothamnium from the other genera of the tribe chareae. In 2 controversial species of the genus Chara, C. hornemannii and C. buckellii, the present study reveals that the central cells of their main axial nodal complexes do not subdivide. The transfer of these two species to the genus Lamprothamnium by Daily (1) may not be appropriate.     

SYSTEMATIC ANATOMY OF THE FLOWER AND FRUIT OF COROKIA

Corokia, a genus of shrubs of New Zealand, eastern Australia, and certain Pacific islands, was first placed in Rhamnaceae, later in Cornaceae, and most recently next to Argophyllum, subfamily Escallonioideae, in Engler's monograph of the Saxifragaceae. Most manuals still list Corokia under Cornaceae from which it is readily excluded by several characters, including pluricellular T-shaped trichomes, ligulate petals, vascular bundles running longitudinally through the center of the inferior gynoecium, histology and germination of the woody endocarp, and a conspicuous subepidermal layer of tannin-containing cells. Corokia collenettei, endemic to the isolated island Rapa, retains the most primitive floral characters of the genus. Anatomical comparison of Corokia flowers with flowers of Argophyllum shows similarities that probably indicate affinity, but the relation of these two genera to others in Engler's subfamily Escallonioideae is unclear. Engler's inclusion of Berenice and Carpodetus with Corokia and Argophyllum in a tribe Argophylleae seems especially artificial.     

Phytochemical interrelationships in the Cornaceae

The distribution of iridoids, ellagitannins, proanthocyanidins and other compounds in the Cornaceae and related families is discussed in relation to the various taxonomic treatments. Analysis of the chemical data indicates that: (a) Benthamia and Cynoxylon are the most primitive sub-genera in Cornus, (b) Corokia possesses a chemical pattern consistent with that of the Cornaceae, but Helwingia might better be elevated to family rank, (c) Alangiaceae, Davidiaceae, Garryaceae and Nyssaceae broadly fall into the same pattern as the Cornaceaa and can be placed in a restricted order, Cornales, which excludes Araliaceae, Umbelliferae and Rhizophoraceae, and (d) the Cornales shows affinities to the Saxifragales and the Dipsacales.     

Arum- and Paris-type arbuscular mycorrhizas in a mixed pine forest on sand dune soil in Niigata Prefecture, central Honshu, Japan

Arbuscular mycorrhizas (AM) are the most widespread mycorrhiza in nature and form two morphologies, Arum- and Paris-type. The determining factors defining the two different morphologies are not well understood. In this study, the distribution of Arum- and Paris-type AM was determined in a mixed pine forest. A total of 35 plant species belonging to 20 families and 32 genera were identified and examined for AM colonization and morphological types. AM morphological types in 14 families were confirmed as follows: Arum-type in Rosaceae, Oleaceae, Lauraceae, Vitaceae and Compositae, Paris-type in Aquifoliaceae, Ulmaceae, Araliaceae, Theaceae, Magnoliaceae, Rubiaceae and Dioscoraceae, and both and/or intermediate types in Caprifoliaceae and Gramineae. Plant families whose AM morphological status was previously unknown were clarified as follows: Polygonaceae and Commelinaceae showed Arum-type morphology; Celastraceae, Menispermaceae and Elaeagnaceae had typical Paris-type morphology. The proportion of Arum-type to Paris-type species decreased in the following order: annuals > perennials > deciduous species > evergreen species, and pioneer group > early successional group > late successional group. Evergreen plants had a higher tendency to form Paris-type AM than annuals, perennials and deciduous plants. The results indicate that environmental changes, such as shade during plant succession, control the distribution of plant growth forms in mixed pine forest and may also play a part in the distribution of Arum- and Paris-type morphology. The identity of the plant seems to strongly influence AM morphology, though control by the fungal genome cannot be ruled out.     

Ultrastructure of nuclear inclusions and the separation ofVerbenaceae andOleaceae (incl.Nyctanthes)

TEM observations were carried out on 40 taxa of the familyVerbenaceae and 35 taxa of the familyOleaceae, in order to ascertain distribution, ultrastructure and morphology of the intranuclear proteinic inclusions in the mesophyll parenchymatic cells. The investigated genera amount to some 25% and 60% respectively of the genera of the two families. Inside theVerbenaceae, lamellar inclusions (L-type) occur in 6 out of 23 investigated genera: they are mostly present inside the tribesCitharexyleae andVerbeneae (both belonging toVerbenoideae), while they are absent in other subfamilies. All of the investigatedOleaceae genera show intranuclear crystalline inclusions (C 1-type) of three different shapes. Among theAsteridae this is a character peculiar toOleaceae. They appear to be a well defined natural group, including the controversial genusNyctanthes.     

Phylogenetic relationship of medicinally importantCnidium officinale and Japanese Apiaceae based onrbcL sequences

Cnidium officinale Makino is important medicinally and economically, but its origin is uncertain. The phylogenetic relationship ofC. officinale is provided from the analyses based on the ribulose-1,5-bisphosphate carboxylase/oxgenase gene (rbcL) sequences of 41 species which represent the 34 genera of Aplaceae, the four genera of Araliaceae, and one genus each of Pittosporaceae, Cornaceae, and Caprifoliaceae. The strict consensus tree obtained supports a close relationship ofC. officinale to the Chinese members ofLigusticum, especially toL. chuanxiong. Additionally, the tree shows (1) polyphyly of the genusLigusticum and (2) monophyly of the subfamily Apioideae. Within Apioideae, we recognized some groups in our phylogenetic tree. The grouping is discordant in several respects with the traditional tribal divisions based mainly on fruit morphology.     

PHYLOGENETIC ANALYSES OF THE RED ALGAL ORDER RHODYMENIALES SUPPORTS RECOGNITION OF THE HYMENOCLADIACEAE FAM. NOV., FRYEELLACEAE FAM. NOV., AND NEOGASTROCLONIUM GEN. NOV.1

Systematics of the red algal order Rhodymeniales was investigated using combined large‐subunit nuclear ribosomal DNA (LSU) and elongation factor 2 (EF2) analyses. These data were subjected to distance, parsimony, and Bayesian analyses, and the resulting phylogenies were largely congruent with previously published SSU results in that the four currently recognized rhodymenialean families (Champiaceae, Faucheaceae, Lomentariaceae, and Rhodymeniaceae) were resolved as monophyletic lineages (with the exception of Coelothrix, which is here transferred to the Champiaceae from the Rhodymeniaceae). In addition, taxa presently considered as incertae sedis consisted of two lineages (Fryeella lineage and Hymenocladia lineage). Based on these results, two new families are proposed: (i) the Fryeellaceae fam. nov. to accommodate the genera Fryeella, Hymenocladiopsis, and a new taxon from Tasmania, Australia; and (ii) the Hymenocladiaceae fam. nov., to accommodate Asteromenia, Hymenocladia, and Erythrymenia. In addition to resolving familial relationships, these analyses resolved some novel interspecific affinities, and we propose a new genus, Neogastroclonium gen. nov., for Gastroclonium subarticulatum, a species that differs significantly in both morphology and molecular data from genuine species of Gastroclonium. Relationships among additional faucheacean and lomentariacean taxa were investigated using LSU data only, and these results are discussed. The familial classification of the Rhodymeniales proposed herein is discussed in light of vegetative and reproductive anatomy, most notably the ontogeny of the tetrasporangia.     

CHROMOSOME COUNTS OF COMPOSITAE FROM THE UNITED STATES AND MEXICO

Chromosome counts are reported for 126 taxa representing 122 species and 61 genera of Compositae. First reports include two genera, Stylocline (n = 14) and Chromolepis (n = 19), 17 species, two infraspecific taxa, and one interspecific hybrid. Five additional taxa have chromosome numbers differing from previously published accounts. Carminatia is reinstated to generic status.     

SIGNIFICANCE OF PHYLOGENETIC SYSTEMATICS FOR THE BIOGEOGRAPHY OF THE MARINE RED ALGAE

Hovencamp (1997) recommends that geographical information can be extracted from cladistic analyses of phylogenetic data in which the Earth's history is resolved in terms of vicariance events that established barriers to migration. Nodes in a cladogram that specify two sister groups which do not overlap in their distributions are taken as evidence for a vicariance event and the sequential order of cladogram nodes leads to a procedure whereby the sequence of vicariance events can be reconstructed. For red algae, two such events are the persistence of the northward extension of the eastern end of Gondwanaland across a cool to warm temperature gradient with the formation of present‐day Australasia, and the opening of the Tethyan Ocean followed by closure of the Tethyan Seaway between Africa and Eurasia. Phylogenetic hypotheses related to the first of these events are seen among genera belonging to the Bonnemaisoniaceae, Gracilariaceae, Kallymeniaceae, Gigartinaceae, and Delesseriaceae. A Tethyan origin and distribution is exemplified in part by families that comprise the Solieriaceae complex. Orders such as the Rhodymeniales, Halymeniales and the families Ceramiaceae and Rhodomelaceae contain taxa that fall partly into the first and partly into the second category. Phylogenies are constructed from rbcL sequence data and compared to the morphological evidence. The biogeographical speculations resulting from these observations are preliminary in nature and can only be confirmed or refuted with addtional data and more refined analytical techniques.     

Do plant families with contrasting functional traits show similar patterns of endemism? A case study with Central African Orchidaceae and Rubiaceae

The influence of functional traits on floristic patterns remains poorly understood in tropical rain forests. This contribution explores whether patterns of endemism of plant species are influenced by their life form and mode of dispersal. We used a comprehensive dataset of 3650 georeferenced plant specimens collected in Cameroon belonging to 115 taxa of Orchidaceae and 207 Rubiaceae endemic to Atlantic Central Africa. Species diversity of each family was compared using raw species richness (SR) and an index of species diversity (S _k ) using subsampling procedure to correct for sampling bias. Measures were compared at three scales (square grids of one half-degree and one-degree per side and ecoregions) and according to elevation and continentality gradients. Species similarity between grid cells was measured using the sample-size corrected NNESS index. For both families, SR and S _k decreased along the continentality gradient. In forest habitats below 1500 m altitude, both Orchidaceae and Rubiaceae show similar endemism patterns, but they differ in intensity. At higher altitudes, S _k is higher for orchids due to the presence of endemic terrestrial taxa in grasslands, where the endemic Rubiaceae flora is rather poor. Substantial endemism observed at the ecoregion level and turnover analysis supported the role of the Sanaga River as a phytogeographical boundary. Similar endemism patterns were observed in lowland forests for Orchidaceae and Rubiaceae, even though Orchidaceae are assumed to have better long distance dispersal capabilities. The dispersal ability of Orchidaceae could be limited by the need of specific mycorhizal fungi for seed germination or host specificity for epiphytic orchids.     

CHROMOSOME NUMBERS IN UMBELLIFERAE. III

Chromosome numbers are reported for 156 collections representing 100 taxa of Umbelliferae. Approximately two thirds of the collections are from Mexico, Central and South America and indicate a high percentage of polyploid species in certain genera found in this area. Chromosome numbers for plants belonging to 78 taxa are published here for the first time, previously published chromosome numbers are verified for 18 taxa and chromosome numbers differing from those previously published are reported in seven instances. No chromosome counts have been previously published for nine of the genera included here. Further aneuploidy and polyploidy were found in Eryngium, and Lomatium columbianum has been found to be a high polyploid with 2n = 14x. Every chromosome count is referable to a cited herbarium specimen.     

无量山种子植物区系的特有现象

地处滇中南的无量山地区迄今计有种子植物２０７科,１０２６属,２５４０种,其中东亚特有科１０个,中国特有属２７个,无量山特有种子６７个,这一地区不仅植物种类丰富,而且特有现象较为显著,在对科级持有现象进行较细致的研究后,本文认国无量山具有较多的分类系统上隔离的东亚特有科反映了该地作为东亚古老植物区系的一部分,其地质历史与整个东亚是一致的,且与东亚植物区系的发端密切相关,属的特有现象表明,地处中国特有     

First report of chromosome numbers of the Carlemanniaceae (Lamiales)

The Carlemanniaceae comprises two small genera that are restricted to East Asia: the Carlemannia and Silvianthus. These genera were previously placed in the Rubiaceae or Caprifoliaceae, but are now considered a distinct family that is probably related to the Oleaceae in the Lamiales. The family is still poorly understood with respect to its morphological characteristics. Here, we present the first report of the chromosome numbers of the family using species from both genera, i.e., Carlemannia tetragona, Silvianthus bracteatus ssp. bracteatus, and S. bracteatus ssp. clerodendroides. The species were compared with the chromosome numbers of Oleaceae and associated families using a Bayesian tree that was generated from rbcL and ndhF sequence data from Genbank. C. tetragona had 2n = 30 (x = 15), whereas the two subspecies of Silvianthus had 2n = 38 (x = 19). Comparisons of chromosome numbers support the distinctness of the Carlemanniaceae, not only from the Oleaceae (x = 11, 13, 23), but also from the Tetrachondraceae (x = 10, 11), a family that is possibly related to the Carlemanniaceae and/or Oleaceae in the Lamiales. The notable difference in chromosome number between Carlemannia and Silvianthus, as well as the differences in other characteristics (pollen, seed, and fruit morphology), suggests that the family split early in its evolution.     

Phylogenetic relationships of the Santalales and relatives

Summary Determining relationships among parasitic angiosperms has often been difficult owing to frequent morphological reductions in floral and vegetative features. We report 18S (small-subunit) rRNA sequences for representative genera of three families within the Santalales (Olacaceae, Santalaceae, and Viscaceae) and six outgroup dicot families (Celastraceae, Cornaceae, Nyssaceae, Buxaceae, Apiaceae, and Araliaceae). Using Wagner parsimony analysis, one most parsimonius tree resulted that shows the Santalales to be a holophyletic taxon most closely related toEuronymus (Celastraceae). The santalalean taxa showed approximately 13% more transitional mutations than the group of seven other dicot species. This suggests a higher fixation rate for mutations in these organisms, possibly owing to a relaxation of selection pressures at the molecular level in parasitic vs nonparasitic plants. Outgroup relationships are generally in accord with current taxonomic classifications, such as the grouping of Nyssaceae and Cornaceae together (Cornales) and the grouping of Araliaceae with Apiaceae (Apiales). These data provide the first nucleotide sequences for any parasitic flowering plant and support the contention that rRNA sequence analysis can result in robust phylogenetic comparisons at the family level and above.     

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.