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Context: Confidence in risk analyses for weed biological control (biocontrol) agents is underpinned by knowledge of the phylogenetic associations between the target weed and off-target plant species, with an emphasis on native taxa that co-occur with the weed in its introduced range. The origins of off-target plant species are also considered when assessing potential adverse effects of releasing weed biocontrol agents into the environment. Erigeron bonariensis L. (flaxleaf fleabane), native to South America, is a major cropping weed in North America, Europe, and Australia. Phylogenomic analysis of the weed's tribe, Astereae, for a biocontrol program has put into question the existence of native Australian fleabanes. Aims: We aimed to resolve the establishment means of a supposed native species to Australia by testing its phylogenetic and morphological associations with other Erigeron taxa at a global scale. Methods: Target-sequence capture data were combined with traditional taxonomy. Key results: We rediscovered the closest presumed native relative of flaxleaf fleabane, the rare and declining E. conyzoides F.Muell. (daisy fleabane), during field work in Victoria, Australia. Molecular data and morphology indicated that E. conyzoides and E. acer L. from the northern hemisphere are not distinct. Conclusions: Erigeron conyzoides is very likely not a distinct species endemic to Australia but rather a disjunct population of E. acer. Implications: This finding improves confidence in the host-specificity of candidate biocontrol agents for fleabane in Australia, because we argue that the closest related truly native species is much more distantly related to fleabane than previously thought. Understanding the origins of plant species is critical for accurate risk assessment in weed biological control project as well as conservation management. Our study investigated the rare daisy Erigeron conyzoides , by using genetic data and traditional taxonomy. We discovered that the species is not a distinct endemic species native to Australia, as previously thought, but a disjunct population of the northern hemisphere species E. acer. Photograph by Alexander Schmidt-Lebuhn, © CSIRO. [ABSTRACT FROM AUTHOR]

While conducting phylogenetic analyses of sequence-capture data of Australian members of Asteraceae tribe Astereae, we found that Elachanthus pusillus F.Muell., Isoetopsis graminifolia Turcz. and Kippistia suaedifolia F.Muell. formed a clade with Minuria. We, therefore, conducted an analysis focused on this clade, but with replicate samples of the three smaller genera, and confirmed our results. Kippistia had been synonymised under Minuria between 1876 and 1980, when it was reinstated. Elachanthus and Isoetopsis had not previously been suggested to be part of Minuria , and, indeed, Isoetopsis had been considered so morphologically divergent that even its tribal affiliations were long controversial. However, on closer examination, Elachanthus and Isoetopsis are strikingly similar to Minuria , especially in cypsela and pappus morphology. The evolution of both genera from a common ancestor in Minuria appears plausible in the light of their overall similarity to annual species of that genus such as M. annua , their multiple uniform rows of herbaceous phyllaries with scarious margins, a pappus of scales v. the tendency of Minuria to form pappi with scale-like bases, female outer and male inner florets, and a cypsela indumentum shared with some species of Minuria. We propose the following three new combinations under Minuria : M. pusilla , M. glabra and M. graminifolia. We conducted a phylogenetic analysis of Minuria and related genera and found that Elachanthus , Isoetopsis , and Kippistia phylogenetically nested in Minuria. Before 1980, Kippistia had long been considered part of Minuria. Morphological examination showed many similarities between Eleachanthus , Isoetopsis , and annual species of Minuria. We publish new combinations for four species, synonymising the three smaller genera. (Image credit: Alexander Schmidt-Lebuhn.) This article belongs to the collection Genomics for Australian Plants. [ABSTRACT FROM AUTHOR]

Aster L. is an economically and phylogenetically important genus in the tribe Astereae. Here, the complete plastomes of the eight Aster species were assembled and characterized using next-generation sequencing datasets. The results indicated the complete plastomes of Aster had a quadripartite structure. These genomes were 152,045-152,729 bp in length and contained 132-133 genes, including 87 protein-coding genes, 37-38 tRNA genes, and eight rRNA genes. Expansion or contraction of inverted repeat regions and forward, palindromic, complement, and reverse repeats were detected in the eight Aster species. Additionally, our analyses showed the richest type of simple sequence repeats was A/T mononucleotides, and 14 highly variable regions were discovered by analyzing the border regions, sequence divergence, and hotspots. Phylogenetic analyses indicated that 27 species in Astereae were clustered into six clades, i.e., A to D, North American, and outgroup clades, and supported that the genera Heteropappus, Kalimeris, and Heteroplexis are nested within Aster. The results indicated the clades B to D might be considered as genera. Divergence time estimate showed the clades A, B, C, and D diverged at 23.15 Mya, 15.13 Mya, 24.29 Mya, and 21.66 Mya, respectively. These results shed light on the phylogenetic relationships of Aster and provided new information on species identification of Aster and its related genera. [ABSTRACT FROM AUTHOR]

This study aims to report the complete chloroplast genome of Solidago altissima L., a globally recognized invasive plant. The complete genome length of S. altissima is 152,961 bp; S. altissima has a typical quadripartite structure (including a large single copy of 84,829 bp, a small single copy of 18,084 bp, and two inverted repeat regions of 25,024 bp), which is commonly found in angiosperms. The genome contains 129 genes, consisting of 85 coding sequences, 36 tRNA genes, and 8 rRNA genes. To understand the phylogenetic relationship between S. altissima and its related species, maximum likelihood analysis was performed. The results revealed that S. altissima is closely related to Symphyotrichum subulatum. The findings of the present study could provide fundamental data for the future phylogenetic and evolutionary studies, while also research on species invasion and resolving complexity of S. altissima. [ABSTRACT FROM AUTHOR]

The Astereae subtribe Madagasterinae (Asteraceae) sensu Nesom encompassing four Malagasy genera (Apodocephala, Madagaster, Rochonia and Vernoniopsis) is polyphyletic, as Apodocephala is a member of the Malagasy subtribe Lowryanthinae of the tribe Athroismeae. While Madagaster was shown to belong to Astereae, the phylogenetic positions of Rochonia and Vernoniopsis (now Jalantzia) in this tribe remained to be tested with molecular data. Lowryanthinae presently contains Apodocephala with nine species and the monospecific Lowryanthus. The monophyly of Apodocephala remained to be assessed using a comprehensive sampling. The aims were to: (1) assess the phylogenetic placements of Rochonia and Jalantzia (Vernoniopsis) and test the monophyly of Jalantzia; (2) assess phylogenetic relationships within Lowryanthinae; and (3) re-assess the subtribal and generic limits within the tribe Athroismeae. New phylogenetic analyses based on plastid sequence data confirmed the position of Rochonia in Astereae. Jalantzia (Vernoniopsis) was resolved as sister to the subtribe Lowryanthinae and therefore transferred to Athroismeae. A new subtribe, Jalantziinae, is described to accommodate Jalantzia. Apodocephala is paraphyletic with respect to Lowryanthus, which is formally merged with Apodocephala. A description of the emended subtribe Madagasterinae containing Madagaster and Rochonia is presented. Citation: Bengtson A. & Razafimandimbison S. G. 2024: New subtribal and generic limits in the tribe Athroismeae (Asteraceae) and further disintegration of the subtribe Madagasterinae of the tribe Astereae. – Willdenowia 54: 103–116. Version of record first published online on 25 April 2024 ahead of inclusion in April 2024 issue. [ABSTRACT FROM AUTHOR]

The typification of Aster sedifolius L. (Asteraceae: Astereae) is discussed. Designation of a lectotype is based on consultation of Linnaeus's original material and the literature cited in the protologue. A specimen from the herbarium sheet preserved at UPS [Herb. Burser XV(1): 62 (UPS no. V-174664)] is designated as lectotype. [ABSTRACT FROM AUTHOR]

Chromosome numbers are reported for 53 individuals of 10 species of Solidago L. sect. Maritimae (Torr. & A. Gray) Semple & Beck from eastern Canada and the eastern United States: S. austrina Small, S. chrysopsis Small, S. gracillima Torr. & A. Gray, S. mexicana L., S. pulchra Small, S. sempervirens L., S. simulans Fernald, S. stricta Aiton, S. uliginosa Nutt., and S. virgata Michx. Identifications of nearly all vouchers for 262 previously published counts for the section were confirmed or revised following the treatments of the section by Semple et al. No counts have been reported for the Mexican species S. maya Semple and S. paniculata DC. and for S. uliginosa var. terra-novae (Torr. & A. Gray) Fernald from Newfoundland. Polyploids are documented in six of the 13 species: S. austrina, S. mexicana, S. pulchra, S. stricta, S. uliginosa, and S. virgata. In addition, we provide the first chromosome count for S. chrysopsis (2n = 18) from Florida. All 315 count reports from 231 locations were used to map the cytogeography of all species in the section. [ABSTRACT FROM AUTHOR]

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Chromosome numbers are reported for 209 individuals of Solidago altissima from Canada and the United States. [ABSTRACT FROM AUTHOR]

Chromosome numbers are reported for 154 individuals of Solidago gigantea from Canada, England, France, and the United States. [ABSTRACT FROM AUTHOR]

Chromosome numbers are reported for 349 individuals of 116 taxa and 2 hybrids in 13 genera from Canada and the United States. The majority of the reports are for asters listed in this paper under the generic names Symphyotrichum (93 reports) and Eurybia (51 reports) plus species of Doellingeria, Oclemena, and Sericocarpus and for goldenrods in Solidago (171 reports). Corrected identifications for four previous reports are also listed. The following are first reports for these taxa: Solidago jejunifolia, 2n = 9II from Wisconsin; Solidago fallax var. molina, 2n = 18 from Québec; and Symphyotrichum falcatum subsp. falcatum, 2n = 10 from Northwest Territories. Multiple counts are first reports for a particular taxon in a province or state: e.g., Solidago salicina, 2n = 18 from North Carolina; Symphyotrichum grandiflorum, 2n = 60 from Virginia; and Symphyotrichum welshii, 2n = 16 from Wyoming. The following are all first reports for the province of Prince Edward Island: Solidago nemoralis subsp. nemoralis, 2n = 18; Symphyotrichum lanceolatum var. lanceolatum, 2n = 64, Symphyotrichum puniceum var. puniceum, 2n = 16. [ABSTRACT FROM AUTHOR]

Narrowly lanceolate leaves occur frequently in the genus Aster. It was often employed as a distinguishing character in the taxonomy of this genus. The origin of this particular leaf shape, however, has never been investigated using comparative methods. In this study, we reconstructed a comprehensive phylogeny that includes most species of Aster with narrowly lanceolate leaf. We then gathered data on riparian habitats and the presence or absence of narrowly lanceolate leaves, and investigated the evolutionary association between them in a phylogenetic context. Our analysis indicated that the species with narrowly lanceolate leaves are nested in unrelated lineages of the genus Aster, implying that they originated independently several times. Using Pagel's comparative method of discrete data, we demonstrated a significant correlation between riparian habitats and narrowly lanceolate leaves. We further inferred the sequence of transition of the two characters. This analysis indicated that the sequence of evolution of riparian habitat and narrowly lanceolate leaf form was usually uncertain, but some positive results showed that the occurrence of riparian habitats may not precede the evolution of narrowly lanceolate leaf form. This study provided new insights into the adaptive evolution in a mega-diverse family. In addition, Aster tonglingensis, an unexpected new species with narrowly lanceolate leaves, was discovered and established based on the evidence from morphology, micromorphology and molecular phylogeny. [ABSTRACT FROM AUTHOR]

Meiotic studies in 18 species belonging to 7 genera of the tribe Astereae from various localities of Western Himalaya have been analyzed. The chromosome number has been reported for the first time in Aster albescens (n = 9) and A. indamellus (n = 9). Further, intraspecific variability has been reported for the first time in A. thomsonii (n = 27), Bellis perennis (n = 5) and Myriactis nepalensis (n = 18). In India, the chromosome numbers are reported for first time in Aster himalaicus (n = 9), Brachyactis roylei (n = 9), Erigeron bellidioides (n = 9) and E. borealis (n = 9). B-chromosomes have been reported for the first time in Erigeron acer (n = 9 + 1 − 2B). Besides, most of the populations show laggards, chromosome stickiness and cytomixis from early prophase to telophase-II, leading to the formation of aneuploid cells or meiocytes with doubled chromosome number. Such meiotic abnormalities produce unreduced pollen grains and adversely affect pollen viability. [ABSTRACT FROM AUTHOR]

Chromosome numbers are reported for 133 individuals of 41 taxa and cultivars and four hybrids in the goldenrod genus Solidago from Canada, the United States and botanical gardens in Europe. With the exception of first reports, all of the reports confirm previously published reports. First reports are for the following: Solidago juliae, 2n=36, Texas; S. radula, 2n=36, Arkansas, Texas; S. mexicana, 2n=36, Louisiana, Texas; S. velutina ssp. californica, 2n=36, California. [ABSTRACT FROM AUTHOR]

Background: The anatomical traits associated with water deficit are also observed in plants growing in poor soils. The species may resist water deficit through three main strategies: escape, avoid or tolerate. The Pedregal de San Ángel Ecological Reserve (REPSA), Mexico, is an environment with low nutrient soil and low water availability. It is set on the basalt formation derived from the Xitle volcano eruption. The main vegetation type is characterized as xerophytic shrub. Thus we expect that species growing in this community will show leaf xeromorphic traits and may have any of the three response strategies. We analyzed the foliar anatomy of 52 species of the Asteraceae family at the REPSA because it is the most abundant angiosperm family in the site, showing a wide variety of growth forms and anatomical variation. Results: The foliar anatomies of the studied Asteraceae were highly variable as well as their quantitative traits as revealed by principal component analysis. This agrees with previous studies that found great anatomical variation within the family. Leaves have multiple layered palisade parenchyma and parenchyma bundle sheaths and could not be categorized as xeromorphic because they possess mesomorphic leaf features as simple lamina, single-layered epidermis, and soft large-size glabrous leaves with high specific leaf area. Conclusions: The combination of mesomorphic and few xeromorphic foliar traits with other characters at the genus and tribal level probably has been essential in Asteraceae to colonize various environments, including those with low water and nutrient availability. [ABSTRACT FROM AUTHOR]

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Aim Regions with a mediterranean climate are among the most species-rich regions in the world. They are also among the regions with the greatest number of non-native invasive species. However, not all introduced species become invasive. Previously, we found that non-native Asteraceae closely related to native species are more likely to establish and spread in California, USA. We conducted reciprocal studies in another mediterranean-climate region with high species richness, the Italian Peninsula. Mediterranean Basin invaders in the Astereae mostly originated in temperate North America, whereas the invasive Cardueae of California are primarily from the Mediterranean Basin. Location The Mediterranean Basin ( Italy). Methods Utilizing the first fossil-calibrated molecular phylogenies of the tribe Astereae, we explored the evolutionary patterns among native and non-native taxa within this group. To elucidate the mechanisms driving the observed patterns, we modelled the ecological niches of Astereae species on a global scale and examined correlations between ecological similarity and evolutionary relatedness among taxa. Results Not only were invasive taxa highly clustered among natives, they were also more closely related to natives than were non-invasive introduced taxa. We found that invasive species had higher degrees of niche overlap with native species than did non-invasive introduced species. Moreover, pairwise niche distance among species was significantly correlated with evolutionary time, indicating that the ecological niche is phylogenetically conserved. Main conclusions The results of our study are consistent with those from our work in California, suggesting that introduced Asteraceae taxa that are closely related to native species are likely to become invasive on both sides of the Atlantic. Furthermore, existing ecological attributes seem to drive these evolutionary patterns. We suggest that potential invaders closely related to natives should be considered as high priorities for management. [ABSTRACT FROM AUTHOR]

Chromosome numbers are reported for the first time for 245 individuals of 93 taxa and cultivars and two hybrids from 13 genera from eastern Canada and the eastern United States. Nearly all of the reports are for asters in Symphyotrichum plus Doellingeria, Eurybia, Oclemena, and Sericocarpus, and for goldenrods in Solidago and Euthamia. Corrections or changes in identifications for eight previous reports are also listed. The following are first documented reports for the taxa: Chrysopsis highlandsensis, 2 n = 5II from Florida; Solidago simulans, 2 n = 36 from North Carolina; Solidago villosicarpa, 2 n = 18 from North Carolina; Symphyotrichum fontinale, 2 n = 50 from Florida; Symphyotrichum grandiflorum, 2 n = 30 from North Carolina; Symphyotrichum parviceps, 2 n = 48 from Missouri; and Symphyotrichum rhiannon, 2 n = 48 from North Carolina. A number of the counts are first reports for a particular taxon in a state: e.g., Brintonia discoidea, 2 n = 18 from Alabama; Doellingeria umbellata var. umbellata, 2 n = 18 from Tennessee, Eurybia spectabilis, 2 n = 72 from South Carolina; Symphyotrichum oolentangiense, 2 n = 32 from Tennessee. [ABSTRACT FROM AUTHOR]

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Cyathocline, a small genus, has been treated as a member of subtribe Grangeinae of tribe Astereae (Asteraceae), but has been neglected in molecular phylogenetic analyses of Astereae. Plastid trnL-F and nuclear ribosomal DNA ITS sequences were used to carry out phylogenetic analyses of Cyathocline (represented by C. purpurea) through maximum parsimony and Bayesian analyses. In addition, its karyotype, morphology and micromorphology were also investigated. The results show that in our three phylogenetic trees, C. purpurea is deeply nested within the Blumea clade and/or the Inulinae clade, and is closest to Blumea balsamifera (Inuleae, Inulinae). C. purpurea is similar to Blumea in chromosome size bimodality and to Inulinae in one single large oxalate crystal within each cell of the cypsela epidermis, which, together with molecular evidences, suggests strongly that Cyathocline should be transferred from Astereae to Inuleae subtribe Inulinae. Although C. purpurea has many anomalous features, its most characters still are within a wide range of morphological variations of Blumea. DNA data and the karyotypic character support to merge C. purpurea into Blumea. As a result, the new combination Blumea purpurea (O. Kuntze) W.P. Li was made. [ABSTRACT FROM AUTHOR]

Dysaster cajamarcensis is a spreading broad-leaved shrub named as a new genus and species of the tribe Astereae subtribe Hinterhuberinae collected in northern Peru. It has bisexual disc florets, disc style branches with strong stigmatic lines and hairy appendages, compressed achenes in both ray and disc florets, and papyraceous involucral bracts. [ABSTRACT FROM AUTHOR]

Background and Aims The classification and phylogeny of Eurasian (EA) Aster (Asterinae, Astereae, Asteraceae) remain poorly resolved. Some taxonomists adopt a broad definition of EA Aster, whereas others favour a narrow generic concept. The present study aims to delimit EA Aster sensu stricto (s.s.), elucidate the phylogenetic relationships of EA Aster s.s. and segregate genera. Methods The internal and external transcribed spacers of nuclear ribosomal DNA and the plastid DNA trnL-F region were used to reconstruct the phylogeny of EA Aster through maximum parsimony and Bayesian analyses. Key Results The analyses strongly support an Aster clade including the genera Sheareria, Rhynchospermum, Kalimeris (excluding Kalimeris longipetiolata), Heteropappus, Miyamayomena, Turczaninowia, Rhinactinidia, eastern Asian Doellingeria, Asterothamnus and Arctogeron. Many well-recognized species of Chinese Aster s.s. lie outside of the Aster clade. Conclusions The results reveal that EA Aster s.s. is both paraphyletic and polyphyletic. Sheareria, Rhynchospermum, Kalimeris (excluding K. longipetiolata), Heteropappus, Miyamayomena, Turczaninowia, Rhinactinidia, eastern Asian Doellingeria, Asterothamnus and Arctogeron should be included in Aster, whereas many species of Chinese Aster s.s. should be excluded. The recircumscribed Aster should be divided into two subgenera and nine sections. Kalimeris longipetiolata, Aster batangensis, A. ser. Albescentes, A. series Hersileoides, a two-species group composed of A. senecioides and A. fuscescens, and a six-species group including A. asteroides, should be elevated to generic level. With the Aster clade, they belong to the Australasian lineages. The generic status of Callistephus should be maintained. Whether Galatella (including Crinitina) and Tripolium should remain as genera or be merged into a single genus remains to be determined. In addition, the taxonomic status of A. auriculatus and the A. pycnophyllus–A. panduratus clade remains unresolved, and the systematic position of some segregates of EA Aster requires further study. [ABSTRACT FROM AUTHOR]

The Chiliotrichum group (Compositae: Astereae) is an informal taxonomic group consisting of shrubby daisies that grow mainly in the Andean and Patagonian regions of South America; it is composed of 31 species in 11 genera: Aylacophora, Cabreraea, Chiliotrichiopsis, Chiliophyllum, Chiliotrichum, Haroldia, Katinasia, Lepidophyllum, Llerasia, Nardophyllum, and Ocyroe. We analyzed phylogenetic relationships in the Chiliotrichum group using five DNA regions from two plant genomes: the plastid trnL-trnF and rpl32-trnL(UAG) spacers, the rpl16 intron, and the nuclear ribosomal internal and external transcribed spacers, ITS and ETS respectively. The dataset includes 21 ingroup species representing all the genera, and 10 outgroup species belonging to six genera. Maximum parsimony, maximum likelihood, and Bayesian inference analyses performed on the chloroplast and nuclear data support the monophyly of the group. The four major clades recovered on the basis of the combined nuclear evidence (ITS+ETS) are: (1) Llerasia clade, (2) Nardophyllum clade, (3) Chiliotrichum clade, and (4) a clade formed by Nardophyllum+Llerasia clades. As regards the status of the four non-monospecific genera, Chiliotrichum (2 spp.) and Llerasia (14 spp.) were recovered as monophyletic, whereas the other two, Nardophyllum (5 spp.) and Chiliotrichiopsis (3 spp.), were not recovered as monophyletic. These two are nonetheless recognized as distinct genera because of robust morphological support despite the lack of resolution in the phylogeny based solely on sequence data. The rest of the genera composing the group are monospecific, and they are scattered among the major clades in the group. The only genus with no clear position is Haroldia. An analysis of the morphological data shows that the presence of paleae, believed to function as a defensive structure for the protection of the achenes, is well correlated with other derived head and floret traits such as the number of florets per head and the type of pappus. [ABSTRACT FROM AUTHOR]

The new species names Mairia petiolata, Zyrphelis capensis, Z. glabra, Z. glandulosa, Z. grauii, Z. macrocarpa, Z. nervosa, Z. spathulata, the new subspecies names Mairia hirsuta subsp. robusta, Zyrphelis ecklonis subsp. oligocephala, Z. ecklonis subsp. strictifolia, Z. microcephala subsp. foliosa, Z. microcephala subsp. glandulosa and the new combinations Zyrphelis ciliaris, Z. ciliaris subsp. angustifolia, Z. ciliaris subsp. hirsuta, Z. decumbens, Z. fruticosa, Z. gracilis, Zyrphelis sect. Gymnostephium, Z. leiocarpa, Z. levis, Z. montana, Z. monticola, and Z. outeniquae are validly published. These names originally appeared in the Ph. D. thesis of the second author, Ursula Zinnecker-Wiegand, submitted to the University of Munich, Germany, in 1990. Being printed and distributed to over 50 libraries, this thesis met the formal requirements for effective publication of the International Code of Botanical Nomenclature then in force, but it is no longer effectively published as a result of a retroactive change in the rules adopted at the International Botanical Congress in Vienna in 2005. As result, the new names appearing in the thesis were not validly published and they are validated here. [ABSTRACT FROM AUTHOR]

The Daisies, Bellis and Bellium, form a monophyletic complex within the core Astereae (Asteraceae). Although most early diverging lineages show an African distribution, the core Astereae is today widespread on five continents with the Bellis/Bellium complex as the only representative in the Mediterranean basin. Molecular clock estimates placed the divergence of Astereae from its sister tribe Anthemideae in the Oligocene. Using a combination of three plastid genes, we estimated divergence times for different lineages of the tribe Astereae. This, together with temporal and biogeographical reconstructions using the nrITS region, allows placing and timing of the major lineages of the Bellis/Bellium complex. The age reconstruction places the divergence of the tribe Astereae in the late Miocene (18-19 million years ago), followed by an out-of-Africa dispersal into Asia where the worldwide expansion may have started. Our results suggest that the colonization of the Mediterranean basin by the Astereae started from Eurasia some 10 million years ago. A Messinian early divergence of the Bellis/Bellium complex in the Mediterranean was estimated. However, a parallel 4-million-year delay for the within-genera diversification was inferred, probably related to the establishment of the sclerophyllous Mediterranean forest. Despite a similar time frame for the within-genera diversification, today's species numbers differ considerably between Bellis (15 spp.) and Bellium (five spp.). [ABSTRACT FROM AUTHOR]

• Premise of the study: The abundance of fossils in Antarctica suggests this continent was a center of diversification and a corridor for migration for many austral plant groups until the late Tertiary and may have played a pivotal role in shaping plant distributions in the southern hemisphere. Although the Antarctic flora was largely erased by glaciation during the Pleistocene, at least some Antarctic plant species found refuge on the subantarctic islands. • Methods: We used independent and combined analyses of ITS, ETS, trnK, and trnL DNA sequences to infer phylogenetic relations in Pleurophyllum, a small genus of three species that are endemic to the subantarctic islands of Australia and New Zealand. The inferred phylogeny provided a framework to reconstruct the origin and patterns of diversification in the genus. • Key results: We summarize support for the hypothesis that Pleurophyllum survived episodes of Pleistocene glaciation in the subantarctic islands and that its sisters dispersed northward in response to glacial advance. • Conclusions: The distinctive flora of the subantarctic islands includes some of the last remnants of a once-diverse Antarctic flora. These plants may still retain distinctive features of their ancestors. Studies of endemic plants such as Pleurophyllum are the key to resolving this puzzle. [ABSTRACT FROM AUTHOR]

Chromosome counts are reported for 15 species of the family Asteraceae from Inner Mongolia (People’s Republic of China). This study includes representatives of the tribes Anthemideae ( Artemisia, Chrysanthemum, Filifolium, Hippolytia and Neopallasia), Astereae ( Heteropappus) and Cardueae ( Echinops and Olgaea). The significance of the chromosome counts is discussed for each species. Within the Anthemideae, chromosome counts for Hippolytia alashanensis (2 n = 36) and the tetraploid level of Artemisia eriopoda (2 n = 36) are reported for the first time. The chromosome number of Heteropappus altaicus (Astereae) agrees with previous reports of one (4 x) of the two ploidy levels reported for this taxon. As a complement to the karyological data, genome size of the Cardueae representatives was assessed using flow cytometry. Within this tribe, Echinops gmelini (2 n = 26) and its sister taxon E. acantholepis (2 n = 14) show strongly divergent karyological patterns of difficult interpretation, whereas the count of E. przewalskyi (2 n = 32), assigned here for the first time, coincides with those of its close relatives. In Olgaea tangutica, the chromosome count (2 n = 24) and genome size (2C = 3.01 pg) given here are the first reports for both the species and the genus. [ABSTRACT FROM AUTHOR]

The systematic position of the monoecious rheophyte, Sheareria (Asteraceae), a genus endemic to China, has been long disputed and never rigorously examined. In this study, two molecular datasets (trnL-F, ITS), plus morphological and cytological characters, were used to assess the systematic position of Sheareria. The broader phylogenetic analyses based on the trnL-F data placed Sheareria in the tribe Astereae with strong support. This placement was also supported by the lanceolate style, "Asteroid type" ligule epidermis, yellow anthers, green achenes, and basic chromosome number ofx = 9. Analysis of the tribe Astereae based on the ITS dataset showed that Sheareria and three East Asian genera (Kalimeris, Aster, Rhynchospermum) formed a strongly supported dade characterized by flat, 2-ribbed, glandular disc achenes. Detailed morphological comparisons indicate that Sheareria is more similar to Kalimeris than to Rhynchospernium. Within this dade, Sheareria is distinguished from other genera by its monoecious breeding system (vs. gynomonoecious). Based on fossil and geological evidence, the development of monoecy in Sheareria is discussed. Within Sheareria, only one species, S. nana, is recognized; S. leshanensis, a newly described species, is placed in synonymy. [ABSTRACT FROM AUTHOR]

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Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nardophyllum cabrerae (Asteraceae: Astereae), a new species from western Argentina is described. The new species differs from its closest relative, Nardophyllum lanatum (Meyen) Cabrera, in its non-revolute margins, white corollas, and pappus of unequal scabrid bristles. Two names, Nardophyllum obtusifolium Hook. et Arn. and N. bracteolatum Hauman, were shown not to represent distinct species and accordingly placed in the synonymy of Nardophyllum bryoides (Lam.) Cabrera and Nardophyllum chiliotrichioides (J. Rémy in Gay) A. Gray, respectively. [ABSTRACT FROM AUTHOR]

Essential oils of B. articulata, B. crispa, B. microcephala, Baccharis milleflora, B. myriocephala, B. stenocephala, B. trimera and B. usterii, all of sect. Caulopterae, have been analyzed by GC and GC/MS. Despite the morphological similarity among these species, differences in composition of their essential oil obtained by hydrodistillation and hexane extract could be observed. Special attention was given to Baccharis trimera and B. crispa since their differentiation during early stages is not possible due to the absence of synflorescences. Carquejyl acetate is suggested as a marker for Baccharis trimera, and a fast method of detection of this compound is given. [ABSTRACT FROM AUTHOR]

Guynesomia (Asteraceae: Astereae), a new genus restricted to the western slopes of the Andes mountains in central Chile, is described. Guynesomia is a shrub characterised by raceme-like or panicle-like capitulescences, disciform capitula, alveolate receptacles, pistillate zygomorphic marginal florets with three or four short lobes, and a pappus of two series of subequal scabrid bristles. Diplostephium is the putative closest relative of Guynesomia. The new combination Guynesornia scoparia is based on Nardophyllum scoparium. [ABSTRACT FROM AUTHOR]

Chiliotrichiopsis peruviana Nesom, H. Rob. & Granda, a new species from Dept. Ayacucho in southwestern Peru, is described and illustrated. It is the only rayless species of the genus, now expanded to four species, and the only one that occurs outside of Argentina. Chiliotrichiopsis is one of six shrubby South American genera of Astereae (subtribe Hinterhuberinae) with paleate receptacles. Observations on morphology and a key to these genera provide perspective for the generic placement of the new species. [ABSTRACT FROM AUTHOR]

Complex geographical distribution patterns and agamospermy have united to obscure systematic relationships in the genus Erigeron (400+ species). Sequence data were analyzed from the internal transcribed spacer region of nrDNA (ITS) and 5.8S cistron for 77 taxa including 63 Erigeron species. Results support the North American origin of Erigeron and document that Aphanostephus, Conyza, and three small genera restricted to South America ( Apopyros, Hysterionica, Neja) are all derived from within Erigeron. Phylogenetic data indicate that agamospermy has arisen at least three times in Erigeron and that autogamy has evolved independently in Conyza and in E. sect. Trimorpha. [ABSTRACT FROM AUTHOR]

Intrageneric relationships in the genus Brachycome were investigated by the comparison of nucleotide sequences of the chloroplast gene matK. Evolutionary trends of some morphological and cytological characters were estimated based on the matK tree. The results indicate that Brachycome is divided into four major clades, and circumscription of superspecies based primarily on fruit morphology is not fully supported. Fruit morphology has evolved in parallel from simple to complex structures in several lineages. The ancestral basic chromosome number is x = 9, and lower chromosome numbers are the products of several dysploid reductions from n = 9 in two of four major clades of Brachycome. [ABSTRACT FROM AUTHOR]

The embryology of Felicia bergeriana O. Hoffm, Conyza stricta Willd. and Erigeron bonariensis L. has been studied. The anthers are tetrasporangiate in C. stricta and F. bergeriana and bisporangiate in E. bonariensis. The anther wall consists of epidermis, endothecium, middle layer and tapetum. Binucleate, tetranucleate and 12 nucleate tapetal cells have been observed respectively in E. bonariensis, C. stricta and F. bergeriana. The tapetum forms periplasmodium and endothecial thickenings are formed in all the species studied. Pollen grains are shed at 3 celled stage. The ovule is anatropous, unitegmic and tenuinucellate. The mature embryo sac is 8 nucleate polygonum type in all the species studied. As many as 6 antipodal cells in Erigeron bonariensis and 12 in C. stricta are observed due to secondary multiplication. In F. bergeriana the antipodal cells become 2-4 nucleate. The persistence of antipodal tissue and its penetration into chalazal region confirm haustorial nature. The endosperm is nuclear in E. bonariensis and C. stricta and cellular in F. bergeriana. The outer cells of endosperm form jacket layer which persists surrounding the mature embryo. The embryo development is of the Asterad type and resembles the Senecio variation. [ABSTRACT FROM AUTHOR]

Gundlachia, a genus of shrubs occurring in the Caribbean islands, is treated as comprising two species, one of which has six varieties. Five new combinations are made: Gundlachia corymbosa var. apiculata (Britton & S. F. Blake) M. A. Lane, G. corymbosa var. compacta (Urb. & Ekman) M. A. Lane, G. corymbosa var. cubana (Britton & S. F. Blake) M. A. Lane, G. corymbosa var. foliosa (Britton & S. F. Blake) M. A. Lane, and G. corymbosa var. ocoana (Urb. & Ekman) M. A. Lane. Gundlachia is probably most closely related to Gymnosperma. [ABSTRACT FROM AUTHOR]

Townsendia gypsophila, a new species from Sandoval Co., New Mexico, is described and illustrated. It is a narrowly distributed obligate gypsophile closely related to T. fendleri and T. incana. It overlaps the ranges of the two taxa at the edge of their distributional limits in New Mexico. [ABSTRACT FROM AUTHOR]

The Astereae were surveyed and the genera arranged in 23 informal groups. The generic groups were used to sample representative genera for a cladistic analysis based on morphological characters. The resulting cladogram was used for discussion of evolution and subtribal classification within the tribe. The lower basic chromosome numbers x = 4, 5, 6, and 8 are interpreted as reductions from a primitive x = 9. The subtribe Grangeinae occupies a phylogenetically basal position as sister group to the rest of the tribe. This may be divided into two large groups, largely corresponding to the homochromous Solidagininae and to the heterochromous Asterinae sensu lato, i.e. including the Bellidinae, Hinterhuberinae, Conyzinae, and Baccharidinae. The latter four subtribes are derived within the Asterinae, and hence reduced to synonymy. Several intercontinental relationships indicate that a geographical subdivision of the tribe should be avoided, although in our analysis most of the groups proved to be restricted to one of five major regions. [ABSTRACT FROM AUTHOR]

Osbertia, a stoloniferous group confined to the montane regions of Mexico and adjacent Guatemala, was first proposed as a genus by Greene (1895), but most workers have retained the taxon as part of Haplopappus. It is clearly closer to Noticastrum, Erigeron or Heterotheca than it is to Haplopappus sensu stricto. The present treatment recognizes two species, a widespread highly variable Osbertia stolonifera and a newly described O. chihuahuana from northwestern Mexico. Distribution maps, distinguishing features, full synonymy and illustrations are presented. [ABSTRACT FROM AUTHOR]

In this work, two new flavonoids, oblongifolioside A (1) and oblongifolioside B (2), along with eight known compounds (3–10), are isolated from the leaves of Baccharis oblongifolia (Asteraceae). The new structures are established through spectroscopic data and the known compounds are identified by comparison with data reported in the literature. The compounds (1–10) are evaluated in relation to their antiradical properties. Compounds 1 and 2 are found to exhibit high antiradical activity compared to their respective non-acylated flavonoids. [ABSTRACT FROM AUTHOR]