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1.
A new species ofMadia sectionAnisocarpus from the serpentines of northwest California is described, illustrated and contrasted with its closest relatives. A key to the annual members of the section is presented.  相似文献   

2.
James R. Wells 《Brittonia》1967,19(4):391-394
Polymnia mcvaughii from Jalisco, Mexico, is described as new. This herbaceous species appears to belong in the mainstream of evolution within the genus. It exhibits marked affinities to several species, but most closely resemblesP. oaxacana Schultz-Bip. Illustrations of important features are included, along with a list of key characteristics.  相似文献   

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4.
Senecio ganderi is described as new from San Diego County, California. It is referable to theAurei species-group and is distinguished by its orange-yellow corollas, cordate to subcordate basal leaves, and its restriction to chaparral and recently burned areas.  相似文献   

5.
Coreopsis crawfordii is described and illustrated. It is also compared with themorphologically similar species, C. pringlei and C. rudis , also from Mexico, and a key to all the species of Coreopsis known from Mexico is provided.  相似文献   

6.
Described from the Planalto of Brazil are:Calea quadrifolia, C. heteropappa, andC. abbreviata of sectionMeyeria,C. intermedia of sectionLemmatium, andC. lutea of sectionCalea. The relationships of each are discussed and a key to the nearest relatives of each is provided. Additionally, all butC. intermedia are illustrated.  相似文献   

7.
A new species of Centaurea L. , Centaurea leonidia Kalpoutz. & Constantin. , from two localities west and south-west of the town of Leonidio in eastern Peloponnisos, Greece, is described and illustrated. It belongs to C . sect. Phalolepis , and taxonomically its closest relatives are C. heldreichii Halácsy , a very localized species from south-west Sterea Ellas (Greece) and, surprisingly, C. niederi Heldr., which belongs to sect. Acrolophus. The new species is currently known from two populations of less than 100 individuals each, growing on almost inaccessible cliffs close to the convent of Agios Nikolaos Sintzas (St. Nicolas of Sintza) and the slopes of Poundes summit. Several other Greek endemic species are found in the same areas. Centaurea leonidia is scientifically important as it belongs to a small group of taxa, which, although they are members of sect. Phalolepis , have close allies in sect. Acrolophus. The chromosome number of C. leonidia , 2 n  = 18, counted in root tips, is also reported and illustrated.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 375–383.  相似文献   

8.
Tod F. Stuessy 《Brittonia》1975,27(2):97-102
The genusMoonia of India and Ceylon, traditionally placed in the subtribe Melampodiinae, is shown to have closer affinities withDahlia andHidalgoa of the subtribe Coreopsidinae. Several morphologically heterogeneous taxa are excluded fromMoonia, and the remaining species,M. heterophylla, is described and illustrated.  相似文献   

9.
On the basis of allozyme and cultivation data, and of additional herbarium material, a taxonomic and nomenclatural revision ofTaraxacum sect.Piesis A.J. Richards exKirschner et?těpánek is provided. The section is made up of halophilous, sexually reproducing taxa. InT. stenocephalum Boiss. etKotschy,T. pindicum Kirschner et?těpánek, sp. nov., andT. perenne Kirschner et?těpánek, sp. nov., a tetraploid chromosome number has been recorded, representing the only known case of sexuality at the tetraploid level in the genus. The complex ofT. stenocephalum, includes some geographically and morphologically extreme populations treated as subspecies: subsp.gumusanicum (Soest)Kirschner et?těpánek, comb. nov., subsp.magnum Kirschner et?těpánek, subsp. nov., and subsp.daralagesicum (Schischk.)Kirschner et?těpánek, comb. nov. In addition toT. bessarabicum (Hornem.)Hand.-Mazz., a widely distributed Eurasian species,T. stenocephalum, a complex centred in Transcaucasia and Anatolia, andT. pachypodum H. Lindb., a North African endemic, four new species are described:T. salsum Kirschner et?těpánek, sp. nov., a diploid endemic confined to E Crimea,T. perenne Kirschner et?těpánek, sp. nov., a tetraploid sexual species known only from SW Crimea,T. pindicum Kirschner et?těpánek, sp. nov., a remarkable tetraploid endemic to the Pindos Mts., Greece, andT. salsitatis Kirschner, ?těpänek etYirdirimli, sp. nov., an Anatolian diploid species. Furthermore, a hybrid betweenT. salsum andT. bessarabicum from Crimea (documented on the basis of allozyme data elsewhere) is given a binomial,T. xmesohalobium Kirschner et?těpánek, nothosp. nov.  相似文献   

10.
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   

11.
Two new combinations inSalmea are made in anticipation of their uses in other publications.  相似文献   

12.
New meiotic chromosome counts are reported from 86 populations from Mexico to Ecuador of 13 species ofClibadium (Compositae, Heliantheae). These, plus previous reports, yield a total of 120 counts from 20 of the approximately 39 species recognized in the genus (Arriagada, in prep.). All counts aren=16 with a few fragments or B-chromosomes observed sporadically in some populations. One population, containing what appear morphologically to be interspecific hybrids betweenC. mexiae andC. microcephalum, showed one tetravalent and fragments. Species in both historical sections (Clibadium andTrixidium, created by Candolle and maintained by Schulz) and from the five sections to be proposed in a new classification of the genus (Arriagada, in prep.) have now been counted. The uniformity of chromosome numbers withinClibadium is correlated with observed allopatric distribution of closely related taxa.  相似文献   

13.
The genusBalduina, endemic to the southeastern United States as interpreted here, includes a complex of three species:B. atropurpurea Harper,B. angustifolia (Pursh) Robinson, andB. uniflora Nutt. The first two species have a chromosome number ofn = 18 andB. uniflora hasn = 36. Hybridization experiments demonstrated strong internal reproductive isolating mechanisms. Flavonoid and sesquiterpene lactone data suggest a possible relationship to the tribe Helenieae.  相似文献   

14.
15.
Edwin B. Smith 《Brittonia》1984,36(3):274-275
Retrorsely barbed aristae on a few immature disk achenes ofCoreopsis insularis (Brandegee) S. F. Blake, together with its other characters, suggest that the species would be better treated asCoreocarpus insularis.  相似文献   

16.
Edwin B. Smith 《Brittonia》1983,35(2):147-149
Coreopsis congregata Blake is out of place in the genusCoreopsis. Its achene morphology, pubescence, leaf cutting and geographical range suggest that it would be better treated in the genusCoreocarpus (Coreocarpus congregatus) and that transfer is proposed.  相似文献   

17.
Twenty-six species and eight varieties of Sect.Viscidipubes & Sect.Albibractea are endemic to Asia.Most species of Sect.Viscidipubes are distributed from low to high altitudes and cold areas in the Hengduan-Himalayan Mountains,with only a few species extending to E or S Asia.Sect.Albibractea is distributed mainly in the subtropics and tropics,lower altitudes and moist areas in S & SE Asia,with a few species extending to the Qinling range of China.Both sections are more advanced than the other sections.They were studied by cladistic analysis and outgroup comparison.Data matrix of 55 characters from stems,leaves,inflorescences,female flowers,bisexual flowers,achenes,pollen grains and chemical constitution was employed in separate and combined studies.Eighteen most parsimonious cladograms were generated with 358 steps,consistency index of 0.72 and retention index of 0.87. 1.Within Artemisia,Sect.Viscidipubes and Sect.Albibractea are sister groups to all the other groups. 2.We support the idea to separate Sect.Viscidipubes (incl.Ser.Viscidipubes,Ser.Erlangshanenses and Ser. Pleiocephalea) and Sect.Albibractea (incl.Ser.Albibractea,Ser.Flaccidae and Ser. Anomalae).The authors suggest that Ser.Anomalae include A.deversa and Ser.Erlangshanenses include A.zayuensis and A.yadongensis as well as Ser.Viscidipubes include A.gyitangensis and A.boreali-siamensis.As the result of the cladistic analysis,the authors tend to propose a new series, Ser.Tanguticae,incl.A.tangutica in the section. 3.We consider that SW China,especially W Sichuan,is the speciation center and the tration of the present distribution center.4.A.boreali-siamensis,only in N Thailand,is not related to the widely distributed species in Ser.Pleiocephalae,such as A.atrovirens,A.chingii and A.myriantha,but rather closely related to species,such as A.vexans,A.occidentali-sichuanensis,which are endemic to W.Sichuan and E.Xizang.  相似文献   

18.
A new species,Ivesia paniculata, is described, illustrated and contrasted with its closest relatives. A key to the California five-stamenedIvesia is presented.  相似文献   

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20.
AlthoughViguiera hidalgoana, a new species from Hidalgo, Mexico, bears a superficial resemblance toV. dentata, it is clearly related to certain woody species of seriesGrammatoglossae.  相似文献   

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