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Se presenta la revisión taxonómica de Baccharis sect. Heterothalamus (Less.) Giuliano en Uruguay. Baccharis sect Heterothalamus está representado por las especies Baccharis aliena (Spreng.) Joch. Müll. y Baccharis psiadioides (Less.) Joch. Müll., cuyas distribuciones geográficas están restringidas a las zonas de sierras. El presente estudio incluye el listado de especies, sinonimia, descripciones ampliadas, ilustraciones detalladas y una clave para la identificación de las dos especies.

No presente trabalho, é descrita e ilustrada Hysterionica nebularis, espécie nova, endêmica da região dos "Aparados da Serra" no Rio Grande do Sul (Brasil).

Oceanic islands provide many opportunities for examining modes of speciation in endemic plants, especially using modern molecular methods. Most speciation has been by either cladogenesis, usually resulting in radiated complexes, or anagenesis, yielding single transformed species. Previous genetic studies with available molecular markers, representing a limited sampling of the genome, have suggested that during cladogenesis, species accrue small genetic differences but differ dramatically in morphology. An appropriate archipelago in which to evaluate the genetic consequences of cladogenesis is the Juan Fernández Islands, a national park of Chile. This present study focuses on AFLP and SSR genetic differences among and within populations of six endemic species of Erigeron (Asteraceae), restricted principally to the younger island, Alejandro Selkirk (one to two million years old). Results show that three different genetic lineages exist among these species: (1) E. rupicola and E. stuessyi; (2) E. fernandezianus; and (3) the E. ingae complex (including E. ingae, E. luteoviridis, and E. turricola). The three genetic lines are distinct from each other, and each harbors considerable genetic variation. The three species of the E. ingae complex appear to be segregating genetically but are not yet ecologically divergent. The amount of genetic differentiation among species of Erigeron is less than that already documented among species of Robinsonia (Asteraceae) on the older island (four million years old). Erigeron fernandezianus, occurring on both islands, appears to have originated on Alejandro Selkirk Island and subsequently dispersed and established also on Robinson Crusoe Island. [ABSTRACT FROM AUTHOR]

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]

No presente trabalho, é descrita e ilustrada Hysterionica nebularis, espécie nova, endêmica da região dos “Aparados da Serra” no Rio Grande do Sul (Brasil).

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]

Taxonomic revision of Baccharis sect. Heterothalamus (Asteracerae: Astereae) in Uruguay. A taxonomic revision of Baccharis section Heterothalamus (Less.) Giuliano (Asteraceae: Astereae) for Uruguay is presented. Baccharis sect. Heterothalamus (Less) Giuliano is composed by Baccharis aliena (Spreng.) Joch. Müll. and Baccharis psiadioides (Less.) Joch. Müll., whose geographic distributions are mostly restricted to hilly areas. This study includes a list of species, synonymy, expanded descriptions, detailed illustrations, and a key for the identification of the two species. [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]

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]

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 article describes Exostigma, a new genus of Astereae Compositae, that includes Exostigma notobellidiastrum and Exostigma rivulare, South American species transferred from Podocoma, based on corolla, style and cypsela characters. Exostigma notobellidiastrum have broadly obovate to suborbicular proximal leaf blades and ray floret corollas that are five to 5.2 millimeters long while Exostigma rivulare have narrowly elliptic proximal leaf blades and densely hairy ray floret corollas.

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 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]

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]

• 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]

Abstract: The investigation of the ethanol extract of fresh aerial parts of the Patagonian shrub Nardophyllum bryoides collected in the province of Chubut, Argentina, yielded eleven terpenoids. These include: three seco-ent-halimane diterpenoids (1–3), two ent-halimanes (4–5) and six pentacyclic oleanane and ursane triterpenoids (6–11). Four of these compounds (2, 6, 8 and 11) are hitherto unknown, while two others (1 and 4) have been previously reported but only as synthetic products. Several of these compounds showed moderate cytotoxicity against a human pancreatic adenocarcinoma cell line while compounds 4 and 5 were active at micromolar concentrations. The main component, seco-chiliolidic acid (1), could be isolated from this extract in large amounts, turning N. bryoides into a sustainable source of this bioactive compound. [Copyright &y& Elsevier]

Abstract: Gall-forming insects provide ideal systems to analyze the evolution of host–parasite interactions and understand the ecological interactions that contribute to evolutionary diversification. Flies in the family Cecidomyiidae represent the largest radiation of gall-forming insects and are characterized by complex trophic interactions with plants, fungal symbionts, and predators. We analyzed the phylogenetic history and evolutionary associations of the North American cecidomyiid genus Asteromyia, which is engaged in a complex and perhaps co-evolving community of interactions with host-plants, fungi, and parasitoids. Mitochondrial gene trees generally support current classifications, but reveal extensive cryptic diversity within the eight named species. Asteromyia likely radiated after their associated host-plants in the Astereae, but species groups exhibit strong associations with specific lineages of Astereae. Evolutionary associations with fungal mutualists are dynamic, however, and suggest rapid and perhaps coordinated changes across trophic levels. [Copyright &y& Elsevier]

The article presents a study which evaluates the phylogeny of Hinterhubera group and related Genera (Hinterhuberinae: Astereae) based on the nuclear DNA ITS and ETS sequences. The study uses 20 of the 30 species from the Hinterhubera group and six of seven genera to test the taxonomic changes wherein the materials used were amplified, the DNA was extracted and sequenced. The result shows that the ETS were poorly resolved and the Hinterhubera group's monophyly were not confirmed.

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]

Abstract: The mostly North American subtribe Symphyotrichinae (Asteraceae: Astereae) comprises Canadanthus, Ampelaster, Psilactis, Almutaster, and Symphyotrichum. Intergeneric and interspecific relationships within the subtribe have been investigated in the past, particularly by Nesom [Nesom, G.L., 1994. Review of the taxonomy of Aster sensu lato (Asteraceae: Astereae), emphasizing the new world species, Phytologia 77, 141–297] and Semple [Semple, J.C., 2005. Classification of Symphyotrichum. Available from: ], using morphological and cytological approaches. Symphyotrichum is the largest and most complex genus within the subtribe and includes four subgenera: Symphyotrichum (x =7, 8), Virgulus (x =4, 5), Astropolium (x =5), and Chapmaniani (x =7). In this study we used two nuclear markers, the nrDNA internal transcribed spacer (ITS) and the low-copy nuclear gene glyceraldehyde 3-phosphate dehydrogenase (GAPDH), to resolve intergeneric and interspecific relationships within the subtribe at the diploid level, and to determine whether our phylogenies validate the classifications of Nesom or Semple. Our results confirm the distinct generic status of Canadanthus and Ampelaster, whereas Psilactis and Almutaster form a polytomy with Symphyotrichum. Within Symphyotrichum, subg. Virgulus is monophyletic based on ITS and appears polyphyletic based on GAPDH. Neither the ITS nor the GAPDH analyses support a distinct status for subg. Astropolium, which groups within subg. Symphyotrichum. In general, interspecific relationships within Symphyotrichum are unresolved. Lack of resolution may be interpreted as a case of recent and rapid evolutionary radiation. [Copyright &y& Elsevier]

The article presents a molecular and morphological phylogenetic analysis about the South American Podocominae (Asteraceae: Astereae). The analysis includes the taxa of both South American and Australasian Podocominae and other subtribes of Astereae. The monophyletic characteristic of Microgyne and the morphological characters used to define the subtribe Podocominae are discussed.

Between 1948 and 2008, 668 chromosome number determinations have been reported for individuals of the goldenaster genus Heterotheca Cass. (Asteraceae: Astereae) from Canada, Mexico, and the United States, including 285 newly reported here. This common group of mostly western North American herbaceous annuals and perennials is subdivided into three sections, the most complex of which is section Phyllotheca. Differences of opinion about the taxonomy of the goldenasters, numerous synonyms, and the lack of a comprehensive treatment of the polymorphic villosa complex and other species complexes in section Phyllotheca made it difficult to organize the data into a meaningful discussion of the cytotaxonomy and cytogeography of this genus. Here I present the geographic distribution of all published counts and cytogeography maps of all species of Heterotheca, assigning taxa following recent taxonomic revisions. The sample sizes for species sampled ranged from 1 to 228 reports. All species have a base number of x = 9. Only diploids (2n = 9II or 2n = 18) were found in Heterotheca oregona (Nutt.) Shinners (the single species of sect. Ammodia) and in the three species of section Heterotheca. Both diploids and (or) tetraploids were found across 18 sampled species of section Phyllotheca, with the frequency varying among them; nine species are known only at one ploidy level (either diploid or tetraploid; three species each). Only four triploids (2n = 9III or 2n = 27) were encountered in section Phyllotheca; two were putative interspecific hybrids. One new nomenclatural combination is proposed: Heterotheca inuloides var. leptoglossa. [ABSTRACT FROM AUTHOR]

The eurybioid asters Oreostemma, Herrickia, Eurybia, and Triniteurybia form a complex that is part of the North American clade of tribe Astereae. They comprise 31 species of perennial herbs that are widely distributed on the continent. Previous analyses had shown poor resolution among the four genera and among the species, particularly within Eurybia (23 spp.), which includes diploids and polyploids. We investigated phylogenetic relationships within the group using the nuclear ribosomal ITS and ETS regions, in separate and combined parsimony and Bayesian analyses. We detected incongruence between the ITS and ETS regions when polyploids were included, and so only diploids were considered in the combined analyses. Eurybia pygmaea (Lindl.) G.L. Nesom is confirmed as a member of Symphyotrichum; Eurybia is monophyletic once this species is re-classified. The eurybioids form a paraphyletic grade with Oreostemma, sister to the remaining taxa, followed in succession by Herrickia, Eurybia, and Triniteurybia, and with the latter genus sister to subtribe Machaerantherinae. Thus the xeric Machaerantherinae (x = 6, 5, 4) is nested within the grade of mesic eurybioids (x = 9). Although largely grouping together, the polyploid taxa of Eurybia apparently do not constitute a clade and their relationships to the diploid taxa and to each other could not be assessed further. Among the diploids, two clades emerge: one including the western Eurybia integrifolia (Nutt.) G.L. Nesom and Eurybia sibirica (L.) G.L. Nesom, and the southeastern Eurybia eryngiifolia (Torr. & A. Gray) G.L. Nesom; and a second including the western Eurybia radulina (A. Gray) G.L. Nesom, the eastern cordate-leaved (sect. Eurybia) and the narrow-leaved, mostly coastal plain species of Eurybia. Our analyses, therefore, do not support the current classifications of Eurybia. [ABSTRACT FROM AUTHOR]

The article reports the revision of the name of two species of South American Microgyne. The author claims that the synonymy of Microgynella to Microgyne is not valid and illegitimate. The new species Microgyne marchesiana and Microgyne trifurcata were described including their fruit and seed anatomy, etymology, distribution and habitat, and phenology. Illustrations of the two species were also provided.