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1.
Phylogenetic relationships among 13 species in the tribe Mutisieae and a single species from each of three other tribes in the Asteraceae were assessed by chloroplast DNA restriction site mapping. Initially, 211 restriction site mutations were detected among 16 species using 10 restriction enzymes. Examination of 12 of these species using nine more enzymes revealed 179 additional restriction site mutations. Phylogenetic analyses of restriction site mutations were performed using both Dolio and Wagner parsimony, and the resulting monophyletic groups were statistically tested by the bootstrap method. The phylogenetic trees confirm an ancient evolutionary split in the Asteraceae that was previously suggested by the distribution of a chloroplast DNA inversion. The subtribe Barnadesiinae of the tribe Mutisieae is shown to be the ancestral group within the Asteraceae. The molecular phylogenies also confirm the paraphyly of the Mutisieae and provide statistical support for the monophyly of three of its four currently recognized subtribes (Barnadesiinae, Mutisiinae, and Nassauviinae). The fourth subtribe, Gochnatiinae, is shown to be paraphyletic. Within the subtribes, several closely related generic pairs are identified. Chloroplast DNA sequence divergence among genera of the Asteraceae ranges between 0.7 and 5.4%, which is relatively low in comparison to other angiosperm groups. This suggests that the Asteraceae is either a relatively young family or that its chloroplast DNA has evolved at a slower rate than in other families.  相似文献   

2.
The Guyana Highland-centred genera, or Stenopadus group, are a complex of species that belong to the tribes Mutisieae and Stifftieae of Asteraceae. The pollen morphologies of 29 species, from 12 of 13 genera of this complex, are described and illustrated using light and scanning electron microscopy. The exine sculpture and structure are highly significant. Four exine types, previously characterized, were distinguished: Gongylolepis , Wunderlichia , Mutisia , and Stenopadus . The characterization of the Stenopadus exine type is enlarged here. These exine types led to the recognition of four well-defined pollen types, whereas the spine length and exine thickness characterized six subtypes. Pollen types circumscribe genera or groups of genera, and some subtypes distinguish species. The pollen morphology within the complex is discussed in relation to the rest of Mutisioideae and other palynologically allied tribes of Cichorioideae. There is little correlation between pollen types and tribes; only the Stenopadus exine type is exclusive to the Stifftieae tribe. The remaining types are shared by the two tribes of the complex. Pollen morphology supports the hypothesis that this group of genera is close to the Gochnatia complex and the Cardueae tribe.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 327–340.  相似文献   

3.
A new species, Erythrocephalum jeffreyanum , belonging to the tribe Mutisieae (Asteraceae), is described and illustrated. Differences between the new species and E. zambesianum , the most similar species, are listed.  相似文献   

4.
A new species, Dicoma swazilandica , belonging to the tribe Mutisieae (Asteraceae) is described and illustrated. Differences between the new species and D. anomaia , the most similar species, are listed.  相似文献   

5.
Adenocaulon andEriachaenium are two problematic genera because their tribal and subfamilial placement in Asteraceae is uncertain. Previous cladistic analyses based on molecular data undertaken to analyze the relationships within Asteraceae, placeAdenocaulon in the tribe Mutisieae (Cichorioideae). This paper investigates cladistic relationships amongAdenocaulon andEriachaenium and tribes of subfamilies Cichorioideae and Asteroideae using morphological data. Thirty-eight characters were scored across 52 genera selected as exemplar taxa to represent the current classification system. In the analysis (one tree, length = 86, c.i. = 0.55, r.i. = 0.64)Adenocaulon andEriachaenium are sister taxa and appear as an isolated clade nested in Cichorioideae. A new, tentative position among the tribes of the paraphyletic Cichorioideae is proposed for these two isolated genera.  相似文献   

6.
An investigation of nine representative species of the tribe Mutisieae yielded some new results of chemotaxonomic interest. Some new sesquiterpenes and coumarins have been characterised by spectroscopic methods. 5-Methylcoumarins appear to be characteristic of the tribe.  相似文献   

7.
Hansen, H. V. 1988. A taxonomic revision of the genera Gerbera sect. Isanthus, Leibnitzia (in Asia), and Uechrrirzia (Compositae, Mutisieae). - Nord. J. Bot. 8: 61–76. Copenhagen. ISSN 0107–055X.
The Asiatic part of Compositae tribe Mutisieae subtribe Mutisiinae scapose group is revised. It includes one section of the genus Gerbera , sect. Isanthus with 6 species: G. maxima, G. raphanifolia, G. delavayi, G. henryi, G. nivea , and G. gossypina , the genus Leibnitzia with 4 species, L. anandria, L. knorringiana, L. nepalensis , and L. ruficoma , and the genus Uechtrirzia with 3 species, U. kokanica, U. armena , and U. lacei . The species are mainly distributed in the Himalaya Region and W. China (Yunnan), but some occur in S. USSR, and L. anandria is widespread; Leibnitzia probably also occurs in Central America with 2 endemic species. A distribution map showing the Asiatic range of Gerbera piloselloides (sect. Piloselloides ) is presented.  相似文献   

8.
The investigation of further species of the tribe Mutisieae afforded in addition to already known compounds a new sesquiterpene derived from bisabolene, a new chromene, two benzofurans and two geranyl derivatives of typical coumarins. The chemotaxonomic importance of these compounds is discussed briefly.  相似文献   

9.
A new species from Angola, Pleiotaxis angolensis (tribe Mutisieae, Asteraceae), is described. We detail the principal differences from the most similar taxon, Pleiotaxis subscaposa .  相似文献   

10.
The investigation of three further species belonging to the subtribe Gochnatiinae, tribe Mutisieae, afforded in addition to known compounds two new eudesmane derivatives and two new germacranolides, closely related to albicolide and salonitenolide. The structures are elucidated by spectroscopic methods and some chemical transformations. The chemotaxonomic aspects are discussed briefly.  相似文献   

11.
 The tribal affinities of Cratystylis and Haegiela were assessed using three chloroplast DNA sequences, the trnL/F spacer, the trnL intron and the matK coding region. The outgroup was represented by two species of the subfamily Barnadesioideae, whereas one to seven genera (45 species including Cratystylis and Haegiela) of the tribes of the Asteroideae [Anthemideae (6 genera), Astereae (7), Calenduleae (2), Gnaphalieae (7), Heliantheae s.l. (5), Inuleae s.str. (3), Plucheeae (3), Senecioneae (4)] and Cichorioideae, [Arctotideae (1), Cardueae (2), Lactuceae (2), Liabeae (1), Mutisieae (1) and Vernonieae (1)] comprise the ingroup. Phylogenetic analysis indicates that Cratystylis has strong support as a member of the tribe Plucheeae, whereas Haegiela is a member of Gnaphalieae. At some point in their taxonomic history, both genera have been placed in these tribes and there are good morphological and chemical characters that justify these placements. The monotypic Haegiela was once included in Epaltes (Plucheeae) and this study has confirmed the need for the separation of the two genera. The genus Cratystylis appears to be monophyletic. Received August 26, 2002; accepted September 19, 2002 Published online: February 7, 2003  相似文献   

12.
Chromosome counts are reported for 76 taxa and 2 natural hybrids of tribe Senecioneae (Compositae). First counts are reported for several species of Senecioneae as well as for the genera Cadiscus and Whitneya. New chromosome numbers are added to those previously known in Arnica, Cacalia, and Senecio. Additional counts from Arnica support our previous suggestion that x = 19 for this genus. It is assumed that observed meiotic irregularities are associated with apomixis in this genus. Basic chromosome numbers for various New World sections of Senecio are proposed, and certain problems of sectional relationships in this genus are discussed. Chromosome numbers and plant morphology of Cadiscus, Hulsea, and Whitneya indicate that these genera should be removed from Helenieae to Senecioneae. The possible affinity of the anomalous genus Adenocaulon with Mutisieae is discussed. Data presented in the paper further support our earlier proposal that the basic chromosome number for Senecioneae is x = 10.  相似文献   

13.
One hundred and ninety-three new counts are reported for the tribe Heliantheae of Compositae, mostly based on determinations of meiotic material, including first counts for the genera Adenothamnus, Chrysogonum, Enceliopsis, Guardiola, Isocarpha, Lipochaeta, Otopappus, and Oyedaea, as well as first counts for 66 species. The original counts are discussed in relation to those previously reported for the tribe, by genera and subtribe. Two-thirds of the approximately 150 genera and more than a third of the roughly 1500 species have now been examined. The incomplete knowledge of generic relationships in the tribe often make the interpretation of these chromosome numbers difficult. Three observations are documented and discussed: (1) genera with low chromosome numbers are few; (2) genera with aneuploid series are abundant; and (3) the original basic chromosome number in the tribe is probably in the range of x = 8 to x = 12.  相似文献   

14.
Recent molecular studies in Asteraceae have divided tribe Mutisieae (sensu Cabrera) into 13 tribes and eight subfamilies. Each of the major clades is well supported but the relationships among them are not always clear. Some of the new taxa are easily characterized by morphological data but others are not, chief among the latter being three subfamilies (Stifftioideae, Wunderlichioideae and Gochnatioideae) and the tribe Hyalideae. To understand evolution in the family it is critical to investigate potential morphological characters that can help to evaluate the basal lineages of the Asteraceae. The data for this study were taken from 52 species in 24 genera representing the basal groups in the family. Many characters were examined but most of the useful ones were from reproductive structures. Several apomorphies supported a few of the clades. For instance, members of subfamily Wunderlichioideae (Hyalideae and Wunderlichieae) share predominantly ten‐ribbed achenes and members of Wunderlichioideae + Stifftioideae share two synapomorphies: 100–150 (200) pappus elements, arranged in (three) four or five series. These apomorphies can be viewed as an indication of a sister‐group relationship between the two subfamilies as the placement of Stifftieae was not well resolved by the molecular data. Members of Wunderlichieae are characterized by having a paleaceous receptacle, style branches that are strongly papillose above and below the bifurcation, and a pappus of scales. Hyalis and Ianthopappus (Hyalideae) share venation type and an apiculate anther appendage but these are also found in Gochnatieae. Other clades have fewer supporting characters. These characters are just a beginning. Cladograms with morphology characters plotted, illustrations and a key to the basal grade of Asteraceae are provided. © 2013 The Linnean Society of London  相似文献   

15.
Abstract. The genera Placusa Mannerheim and Euvira Sharp share the 4, 4, 5 tarsal segmentation with other members of the aleocharine tribe Bolitocharini. Placusa has usually been placed together with other subcortical members of this tribe into the subtribe Homalotina or its taxonomic equivalent. Members of the very distinctive genus Euvira are not subcortical. The systematic position of this latter genus has been uncertain though it has been most often placed in the tribe (or subtribe) Autaliini. Because of the striking differences in habitus and habits of members of these two genera, they have always been considered to be, at most, distantly related within the Bolitocharini. Study of the larvae and adults of both genera has revealed that they share a diverse set of derived features (eight in adults; ten in larvae). Many of these are unique to the Aleocharinae. These features are described and illustrated and a discussion of their systematic importance is provided. Four conclusions are drawn: (1) Placusa and Euvira form a monophyletic group; (2) these two genera are misplaced in the tribe Bolitocharini; (3) these two genera do not share derived features with members of any other described tribe of aleocharines; and (4) Placusa and Euvira must be grouped into a redefined tribal level taxon, the Placusini. The tribe Placusini is defined and its composition and systematic placement discussed.  相似文献   

16.
The surface sculpturing of the pollen of some species of the taxonomically widely separated genera Harpalyce (tribe Brongniartieae), Camoensia (tribe Sophoreae), Millettia (tribe Tephrosieae), and of the monotypic Dahlstedtia (tribe Tephrosieae) which have large red or white flowers adapted for pollination by birds or bats, is coarsely rugulate or verrucate. Related taxa with small insect pollinated flowers have pollen with simple reticulate or perforate surface sculpturing. The exine stratification of Alexa and Castanospermum (tribe Sophoreae), genera with large red bird-flowers, is complex with a layer of tectal columellae and differs from that of other genera in the tribe Sophoreae which have a normal pollen wall structure. These modifications of pollen structure and sculpture appear to be the result of convergent evolution and a secondary adaptation to pollination. The taxonomic and functional significance of the observations are briefly discussed.  相似文献   

17.
Systematic wood anatomy of the tribe Guettardeae (Rubiaceae). The wood anatomy of nearly all genera of the Guettardeae (Rubiaceae, Guettardoideae) has been examined, and in this respect the tribe is heterogeneous. Suggestions are made for a delimitation of the tribe. Guettarda, Bobea, Antirhea, Malanea and Chomelia Jacq. are sufficiently similar in their wood anatomical characters to warrant retention in the same tribe. Machaonia, Timonius and Dichilanthe are anomalous. Suggestions are given for taxonomic revisions of some genera based on their wood anatomy.  相似文献   

18.
The largest family of flowering plants Asteraceae (Compositae) is found to contain 12 major lineages rather than five as previously suggested. Five of these lineages heretofore had been circumscribed in tribe Mutisieae (Cichorioideae), a taxon shown by earlier molecular studies to be paraphyletic and to include some of the deepest divergences of the family. Combined analyses of 10 chloroplast DNA loci by different phylogenetic methods yielded highly congruent well-resolved trees with 95% of the branches receiving moderate to strong statistical support. Our strategy of sampling genera identified by morphological studies as anomalous, supported by broader character sampling than previous studies, resulted in identification of several novel clades. The generic compositions of subfamilies Carduoideae, Gochnatioideae, Hecastocleidoideae, Mutisioideae, Pertyoideae, Stifftioideae, and Wunderlichioideae are novel in Asteraceae systematics and the taxonomy of the family has been revised to reflect only monophyletic groups. Our results contradict earlier hypotheses that early divergences in the family took place on and spread from the Guayana Highlands (Pantepui Province of northern South America) and raise new hypotheses about how Asteraceae dispersed out of the continent of their origin. Several nodes of this new phylogeny illustrate the vast differential in success of sister lineages suggesting focal points for future study of species diversification. Our results also provide a backbone exemplar of Asteraceae for supertree construction.  相似文献   

19.
The generic classification of moths of the tribe Macariini Guenée is reviewed critically, and a revised classification is presented. The review is based on a survey of species across the taxonomic and geographical range of the tribe. In the new framework, the number of genera is reduced considerably. Two genera are very large: Macaria Curtis (mainly New World) and Chiasmia Hübner (largely Old World) together include over half of all macariine species. Twenty-three genera are accepted in the tribe; the identity of two genera remain uncertain. No single character defines the tribe, but diagnostic features include one or more of the following: the presence of enlarged setae ('horns') on the uncus in the male genitalia; a divided valva; and a modified condition of sternum A8 in the male. The taxonomic history of the tribe is reviewed briefly and the problems of previous systems are explained mainly by the regional approach adopted. A diagnosis is presented for each genus. © 2002 The Linnean Society of London, Zoological Journal of the Linnean Society , 2002, 134 , 257–315.  相似文献   

20.
The phylogenetic relationships of the genera in the geometrid tribe Scopulini (Lepidoptera: Sterrhinae) were examined using 141 characters of adult morphology and ecology. The study material included 92 species, representing all previously recognized genera and covering the morphological variation and full geographical range of the tribe. The cladistic analysis resulted in 20 equally parsimonious trees and a strict consensus cladogram based on these was well resolved. A majority of the recovered synapomorphic characters have been used previously in the taxonomy of the tribe. However, many novel characters were found in the sclerotized structures of the thorax. Many previously recognized genera were found to be nonmonophyletic and based on the present revised, synapomorphy-based classification, the number of recovered genera is reduced considerably. Twenty new generic synonyms and 90 new or revived species combinations are proposed. Seven genera are considered valid, with the large genus Scopula Schrank including over 85% of all species in the tribe. The taxonomic history of the tribe is reviewed and the problems of earlier classifications are discussed. A key to the genera is presented, although an informal diagnosis is preferred. All recognized genera are illustrated and a revised world checklist of the Scopulini is presented.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 473−530.  相似文献   

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