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The recent merger ofPlummera intoHymenoxys is followed here. The two previously recognized species ofPlummera are here treated as a single polymorphic species ofHymenoxys, H. ambigens, consisting of three varieties: var.ambigens from the Mescal, Santa Teresa, and Pinaleno Mountains of southeastern Arizona; var.floribunda from the Chiricahua, Dos Cabezas, Dragoon, Little Dragoon, and Mule Mountains of southeastern Arizona; and var.neomexicana described here from the Animas and Peloncillo Mountains of southwestern New Mexico.  相似文献   

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Verbesina barrancae, a new species of Compositae (Heliantheae) from Jalisco, México, is described and illustrated. It is morphologically similar toVerbesina crocata but differs in characteristics of inflorescence, anthers, and achenes as well as in form of pollen, size and number of spinules, size of colpus transversalis, and index of polar area.  相似文献   

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Bletia purpurea is the most widespread species in its genus. Morphological variation has been recognized throughout the range of its distribution. In this paper, the morphological variation from 63 populations (583 individuals) ofBletia purpurea is assessed to determine whether more than one species were present. Forty-four quantitative and qualitative characters were examined by univariate analyses and exploratory multivariate analyses. Univariate analyses indicate that quantitative characters such as lateral sepal width, petal. width, lip length, and lip width are significantly different for populations from Acazónica, Mexico. Floral parts in the populations from Acazónica are the smallest among all populations. Qualitative characters such as petals covering the lip midlobe and horizontal lip position are found exclusively in the same populations. We concluded that these populations should be described as a new species,B. riparia. Multivariate analyses indicated that morphological variation among the other populations cannot be ascribed to geographic distribution or ecological factors.  相似文献   

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In addition to known compounds, the floral parts of Viguiera radula afforded two new sesquiterpene lactones. All compounds were detected in glandular trichomes, which were micromechanically collected from the anther appendages and analyzed by HPLC. Structure identification was performed by NMR and MS techniques.  相似文献   

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Chloroplast DNA variation was examined for 79 species of Verbesina and 24 outgroups. Two independent analyses of the data were performed. An intergeneric study to elucidate the phylogenetic relationships of Verbesina used 22 genera, most of which are regarded in the literature as closely related to Verbesina. Coreopsis and Hymenoxys served as outgroups for this analysis. The 16 6-bp (base pair) restriction endonucleases used in the intergeneric study revealed 263 phylogenetically informative sites. Wagner analyses of these characters resulted in four equally parsimonious trees with a length of 857 steps and a Consistency Index of 0.492. Results from this study indicate that Verbesina is monophyletic, a member of the tribe Heliantheae, and that its sister taxa are the mostly Mexican genera Podachaenium, Squamopappus, and Tetrachyron. The infrageneric study of Verbesina included species belonging to all of its infrageneric taxa, except the monotypic sect. Stenocarpha. The 17 6-bp restriction endonucleases used in the infrageneric study revealed 137 sites 77 of which were phylogenetically informative. Wagner analyses of these characters generated 180 equally parsimonious trees with a length of 158 steps and a Consistency Index of 0.786. The genera Podachaenium, Squamopappus, and Tetrachyron served as outgroups. Two major clades, which correspond to traditional divisions of the genus based on leaf arrangement, are supported by the study. No support was found for the monophyly of seven of the 11 sections examined; further sampling of sections Lipactinia, Ochractinia, Verbesina, and Ximenesia is needed. Results support a major reassessment of the traditional infrageneric classification of the genus and provide the basis for the reevaluation of the sectional taxonomy of Verbesina. These studies support a North American origin for the genus with several independent introductions into South America producing significant diversity, especially in the Andean region.  相似文献   

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A taxonomic study of the genusDelilia is presented. Two species are recognized:D. biflora, a widespread weed of tropical and subtropical regions of the New World, extending from Mexico to northern Argentina and recently introduced in the Cape Verde Islands; andD. repens, endemic to the Galapagos islands. A key to the species, illustrations, distribution maps, and complete synonymy are presented.  相似文献   

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We restrict the genusLipochaeta to the allopolyploid species of the typical section.Lipochaeta s.str. is interpreted to be the result of an intergeneric hybridization betweenMelanthera and a presently unknown taxon, perhaps of the genusWedelia. Lipochaeta is characterized, in addition to its allopolyploidy (n=26), by having both flavonols and flavones, disk corollas with 4 lobes, achenes tuberculate at maturity, the disk achenes flattened to slightly biconvex, and ray achenes obcompressed.Lipochaeta sect.Aphanopappus andWollastonia are here reduced to synonymy underMelanthera. We transfer 14 HawaiianLipochaeta and one New Caledonian species as well as the AsianWedelia prostrata toMelanthera. These transfers, along with the species in Africa and North America, bring the number of species in the genus to 35.Melanthera is delimited by an abruptly narrowed to truncate and flattened top of the achene, (0−)1–15(−20) often unequal, ciliate or barbellate, caducous pappus bristles immediately surrounding the corolla, involucral bracts and receptacular paleae with many veins forming longitudinal striations, and n=15. The florets are 5-merous, the corollas are yellow or white, and rays are absent (in white-flowered species) or present and neutral or fertile. In dealing with species formerly placed inLipochaeta, the GalapagosL. laricifolia is here transferred from the illegitimate generic nameMacraea toTrigonopterum and the BrazilianL. goyazensis is transferred toAngelphytum. We maintain the earlier reduction ofEchinocephalum underMelanthera and reduce all three taxa originally described in it to one,M. latifolia.  相似文献   

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The 19 species of the genus Mandevilla in Mexico and Central America are treated synoptically. New synonymy is provided and a new species, Mandevilla rigidifolia, is described.  相似文献   

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Ticorea comprises five species, which occur in the Guianas, throughout the Amazonian basin, and on the lower eastern slopes of the Andes in Ecuador, Peru, and Bolivia. Two of the five are described here as new: T. diandra, from eastern Ecuador and adjacent Peru, and T. froesii, from Maranhão and Pará, Brazil.  相似文献   

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The genus Ischioscia Verhoeff, 1928 is reviewed. 26 species are considered valid. A key for their identification is given, as well as a map showing the geographic distribution. The known range of the genus covers a large area from the central Amazon region to the mountains of Guatemala. The species of Ischioscia have a typical “philosciid” habitus (“runner” type); they can be distinguished from other Neotropical species with similar habitus by the following apomorphies: (1) male pereiopod 1 carpus enlarged to a plate-like extension, (2) scale field on male pereiopod 1 covering entire frontal side of the carpus, (3) male pereiopod 7 ischium with a ventral scale field, (4) dactylus in both sexes with a long inner claw. The groundpattern of Ischioscia is reconstructed, and an analysis of the phylogenetic relations within the genus is made on the basis of morphological data. The species are very similar to each other, most differences are found in the male structures of sexually dimorphic features. Ischioscia sturmi (Vandel, 1972), I. amazonica Lemos de Castro, 1955 and I. bolivari Vandel, 1968 are redescribed in detail.  相似文献   

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Ferris CD 《ZooKeys》2010,(71):49-70
Based on genitalic studies, the new genus Pionenta is established for two taxa formerly placed under Antepione. The taxa hewesata and ochreata (and previously associated synonyms) are now synonomized as Pionenta ochreata. Three species of Antepione are now recognized: Antepione thisoaria, Antepione imitata, Antepione tiselaaria with the taxa comstocki, constans, and indiscretata synonomized under Antepione imitata. No new species are described. Adults and genitalia are illustrated, including type specimens.  相似文献   

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The interrelationships within theHeliantheae s. lato and the closely relatedEupatorieae are analyzed and discussed. The basis to this discussion is a cladistic analysis of 141 morphological characters (172 apomorphic states) scored for 97 genera. TheHeleniae s. lato, a subgroup of theHeliantheae s. lato, are paraphyletic, and a monophyletic group corresponding largely to theHeliantheae s. str. is recognized. TheEcliptinae sensuRobinson are polyphyletic. TheCoreopsidinae form an ingroup in theHeliantheae s. str. TheTageteae (Pectidinae) and theMadieae (Madiinae) are two separate branches within the helenioid assemblage of taxa.  相似文献   

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Routine identification of Asteraceae specimens sent to the Herbarium of the University of Texas at Austin has resulted in the discovery of the following taxa:Acourtia ciprianoi (Mutisieae) andCoreopsis bolanosana andVerbesina spooneri (both Heliantheae). All the new species are illustrated.  相似文献   

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Thirteen new species of the genusStevia are described and illustrated from Mexico:S. chilapensis, S. coahuilensis, S. crassifolia, S. ecatepecana, S. filodecaballoana, S. mascotensis, S. mexicana, S. oaxacana, S. oligophylla, S. potosina, S. rotundifolia, S. scabrelloides, andS. viejoana. In addition, two varieties,Stevia aschenborniana Sch. Bip. ex Klotzsch var.occidentalis Grashoff andS. palmeri A. Gray var.constricta Grashoff are herein redefined as being distinct species,S. occidentalis andS. constricta stat. nov.Stevia mexicana resemblesStevia trifida Lagasca but differs in the habit.  相似文献   

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Phylogenetic analysis of chloroplast DNA restriction site data for 76 of the 302 genera of Heliantheae sensu lato using 16 restriction endonucleases reveals that subtribe Ecliptinae is polyphyletic and that its genera are distributed in four different lineages. The ecliptinous genera Squamopappus, Podachaenium, Verbesina, and Tetrachyron (of the Neurolaeninae), along with other members of subtribe Neurolaeninae are the basalmost clades of the paleaceous Heliantheae. The mostly temperate species of subtribe Ecliptinae (exemplified by Balsamorhiza, Borrichia, Chrysogonum, Engelmannia, Silphium, Vigethia, and Wyethia) are strongly nested in a clade with the Mesoamerican monotypic genus Rojasianthe as basal. The genera characterized by marcescent ray corollas traditionally classified in subtribe Zinniinae constitute a strongly supported group sister to Acmella, Spilanthes, and Salmea. The largest clade of ecliptinous genera is the most recently derived group within Heliantheae sampled. This large group of mostly Neotropical lowland genera (variously characterized by their winged cypselae, foliaceous phyllaries, and opposite phyllotaxy and exemplified by Perymenium, Wedelia, and Zexmenia) has been and continues to be the most challenging group from a taxonomic standpoint. The study provides new insights as to their relationships that will have a positive impact in future monographic studies of the group. The genera of the Espeletiinae form a monophyletic clade and are sister to members of the Milleriinae and Melampodiinae. This result is consistent with their traditional taxonomic placement with genera such as Smallanthus with which they share a tendency for functionally staminate disc flowers. The phylogenetically enigmatic genus Montanoa is sister to Melampodium. Members of subtribe Galinsoginae are clustered in two main lineages that correspond to the traditional division of the subtribe based on pappus characteristics. There is no support for the monophyly of subtribe Galinsoginae, and the same results indicate some of its genera are paraphyletic.  相似文献   

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