共查询到20条相似文献,搜索用时 0 毫秒
1.
Taxonomic revision of South American species of Grindelia Willd. has revealed a new species from Argentina, with homogamous capitula and cushion-shaped habit. The taxon is here described and illustrated. 相似文献
2.
A review of the Argentinean specimens ofHaplopappus Cass. has revealed two new species from Mendoza province, both of the sectionHaplopappus:H. boelkei, unique by its caespitose habit and long petiolate leaves, andH. mendocinus, related toH. macrocephalus (Less.) DC.,H. ochagavianus Phil. andH. tiltilensis Phil. 相似文献
3.
T. Tyler 《Plant Systematics and Evolution》2006,261(1-4):39-88
Patterns of variation among all micro-species of Hieracium sect. Hieracium and H. sect. Vulgata known from Denmark and southern Sweden are investigated. Forty-three, possibly independent morphological characters are used. Significant correlations were revealed among the majority of the characters. Multivariate analyses did not reveal any discontinuities in the variation or any discrete groups of species. However, there were obvious correlations between previous taxonomic classifications and the result of the multivariate analyses. Based on the statistical analyses, three sections and 38 informal species aggregates are recognized. H. sect. Bifidum T. Tyler is described anew. The characters that turned out to be most influential in the multivariate analyses, and thus most important for the classification, were the distribution of stellate tomentum on the phyllaries, the amount of glandular hairs and the amount and pigmentation of simple hairs on the phyllaries, the shape of the leaf-base and the regularity of the leaf dentation. The evolution of the group and the taxonomic treatment is thoroughly discussed in the light of the results. 相似文献
4.
Hieracium busambarense (Asteraceae), a new species from calcareous-dolomite cliffs of Rocca Busambra (western Sicily, Italy) is described and illustrated here. 相似文献
5.
Andreas Houben Nicole Thompson Richard Ahne Carolyn R. Leach Dawn Verlin Jeremy N. Timmis 《Plant Systematics and Evolution》1999,219(1-2):127-135
The A and B chromosomes of different karyotype variants (cytodemes A1, A2, A3 and A4) ofBrachycome dichromosomatica were analysed by computer-aided chromosome image analysis and fluorescencein situ hybridisation (FISH). Ribosomal DNA and the B chromosome-specific sequence Bd49 were detected on all B chromosomes. In addition to minor size variation of the Bs, polymorphism of the rDNA and Bd49 position and copy number revealed two major types of B chromosomes. The B chromosomes of all the cytodemes were indistinguishable from each other in length, but that of A3 showed evidence of rearrangements consistent with its long-term geographic isolation. The results presented suggest a monophyletic origin of the B chromosomes ofB. dichromosomatica. 相似文献
6.
Leticia Cabrera R. 《Brittonia》2001,53(3):416-429
Six Mexican species ofAcourtia are described. One of these novelties seems to be related toAcourtia mexicana (Lag. ex D. Don) H. Rob., whose nomenclature has been misunderstood for decades; an exhaustive literature review and examination
of herbarium material supports Robinson’s combination.
Resumen Se describen seis nuevas especies mexicanas deAcourtia. Una de estas novedades parece estar relacionada conAcourtia mexicana (Lag. ex D. Don) H. Robinson, especie cuya nomenclatura ha sido mal interpretada por décadas; una exhaustiva revisión de la literatura así como de material de herbario, apoyan la combinación de Robinson.相似文献
7.
Arabidopsis halleri represents an important model species for the study of phytoremediation. In the Carpathians it is represented by three subspecies: A. halleri subsp. halleri, A. halleri subsp. tatrica and A. halleri subsp. dacica. All three subspecies are diploid with chromosome number 2n = 16. They differ mainly in indument of flower parts, colour of petals and in the position of the longest leaf on stem. A. halleri subsp. halleri occurs in the Eastern and Southern Carpathians and in the northern and eastern part of the Western Carpathians, subsp. tatrica is endemic of the Western Carpathians and subsp. dacica occurs in the Eastern and Southern Carpathians most probably extending in its distribution further to the south to the Balkan mountains. Full synonymy of these three taxa and also a fourth European subspecies, A. halleri subsp. ovirensis is presented including the information on type specimens. Lectotypes are selected for several names. List of the examined herbarium specimens is given as well. 相似文献
8.
Phagnalon rechingeri spec. nova from S Baluchestan (Iran) is described as a species new to science and illustrated; its relationships to other species of the genus, in particular to thePh. woodii group from S Arabia, are discussed.Dedicated to Hofrat Univ.-Prof. DrK. H. Rechinger on the occasion of his 80th birthday. 相似文献
9.
Grindelia coronensis, a new species from the Meseta del Somuncura, Prov. Río Negro, Argentina, is described and illustrated. It is similar toG. chiloensis (Cornel.) Cabrera but it is readily distinguished by its leaves which are conspicuosly differentiated into a obovate blade and a long petiole. 相似文献
10.
Stylotrichium glomeratum (Asteraceae, tribe Eupatorieae, subtribe Gyptidinae) is described from Chapada Diamantina (Bahia, Brazil), where the genus
is endemic. A key to the five species ofStylotrichium is presented.
Descreve-seStylotrichium glomeratum (Eupatorieae, Asteraceae), uma nova espécie da Chapada Diamantina (Bahia, Brasil), onde este gênero é endêmico. é apresentada uma chave para as cinco espécies deStylotrichium.相似文献
11.
G. Kamari 《Plant Systematics and Evolution》1992,182(1-2):1-19
This work examines the cytogeographical distribution, the morphological characters, and the karyotypes of threeCrepis species endemic to Greece (C. sibthorpiana, C. incana, andC. heldreichiana). C. sibthorpiana is diploid (2n = 2x = 8),C. incana is diploid (2n = 2x = 8) and tetraploid (2n = 4x = 16, 17), andC. heldreichiana is always dekaploid (2n = 10x = 40). The Giemsa positive bands, usually pairs of dots, are mainly centromeric inC. incana, while they are terminal inC. sibthorpiana (on the short arm of all chromosomes) and inC. heldreichiana (on both arms of all chromosomes). Intercalary C-bands are scarce and usually variable within karyotypes, individuals, and species. The most variable karyotype both in Feulgen and Giemsa preparations is that ofC. incana, in which also supernumerary chromosomes were observed, which are polysomic to standard set members. On the basis of morphological and karyological data the evolutionary relationships among the threeCrepis taxa are discussed. 相似文献
12.
Lonchocarpus castaneifolius, L. grazielae, L. longiunguiculatus, and L. montanus from Brazil are described and illustrated based on field and herbarium studies. The first species belongs to Lonchocarpus sect. Punctati and is restricted to northeastern Brazil (Bahia state). The other three are included in sect. Laxiflori. Lonchocarpus grazielae is restricted to the southern coastal region (Santa Catarina state), L. montanus is found in northeastern Brazil (Bahia and Piauí states), the west-central region (Goiás and Tocantins states) and the southeast (Minas Gerais state), and L. longiunguiculatus occurs in northeastern (Bahia state) and southeastern (Minas Gerais state) Brazil. 相似文献
13.
Ö. Eren 《Plant Systematics and Evolution》2007,267(1-4):13-23
Turkish representatives of the genus Rhaponticoides Vaill. are examined. A key and distribution map of Rhaponticoides species occurring in Turkey are provided for the first time. R. hierroi Ö. Eren sp. nov., from Bakacak pass in the Western Taurus range, SW Anatolia, allied to R. mykalea (Hub.-Mor.) M. V. Agab. &; Greuter is described as a species new to science and illustrated. Its habitat conditions and conservation status are considered. Pollen micrographs of R. hierroi and R. mykalea are presented using scanning electron microscopy. 相似文献
14.
Summary Vanda longitepala, a new species of orchid from northern Burma is described and discussed. 相似文献
15.
Karen Husum Clary 《Brittonia》1995,47(4):394-396
Yucca linearifolia is described, illustrated, and distinguished from other yucca species. Its distinctive combination of fleshy fruit and narrow,
linear, denticulate leaves sets it apart from all other yuccas.
Se describe e ilustraYucca linearifolia y se discute su separación de otras especies del géneroYucca. La combinación de caracteres tales como el fruto, carnoso y la hoja linear y denticulada la distingue del resto de las especies
del género. 相似文献
16.
Pothos crassipedunculatusSivadasan & Mohanan (Araceae), a new species closely related to the SW. Indian endemic and little known speciesP. thomsonianusSchott is described. It is characterized by the the non-ligulate, shortly vaginate petiole, thickly peduncled inflorescence, broadly ovate spathe and a sessile spadix. It is included in ser.BrevivaginatiEngler of sect.AllopothosSchott. 相似文献
17.
C. A. Simões-Pires S. Debenedetti E. Spegazzini L. A. Mentz N. I. Matzenbacher R. P. Limberger A. T. Henriques 《Plant Systematics and Evolution》2005,253(1-4):23-32
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. 相似文献
18.
A new delphacid (Hemiptera, Fulgoromorpha, Delphacidae) species, Mestus
cruciatus
sp. n. is described based on specimens from Yunnan Province, China. Habitus photos and illustrations of male genitalia are provided. The Mestus species and phylogenetic arrangement of this genus is discussed. A key to the species of Mestus is also provided. 相似文献
19.
Lonchocarpus variabilis, from Mato Grosso do Sul State in Midwestern Brazil, is newly described and illustrated on the basis of field and herbarium studies. It occurs in seasonally deciduous forests and gallery forests at 150–681 m elevation. This species grows in sandy, calcareous, and iron rocky soils. It is similar to L. fendleri, but differs in number of leaflets and shape of the calyx. Moreover, L. variabilis has a staminal tube dilated at the base and anthers with a glabrous base. 相似文献
20.
Italian representatives of the Cardamine pratensis group were investigated using morphometric, karyological, and molecular (AFLP-fingerprinting) analyses. Focus was on resolving the taxonomic and evolutionary position of C. granulosa from Piemonte (NW Italy) and of populations from central Italy, previously included in C. granulosa or C. pratensis s. str. Results show that C. granulosa is a morphologically and genetically well defined diploid species, but is extremely rare and restricted to a small area in Piemonte. Central Italian populations differ from both C. granulosa and C. pratensis s. str., and, although the morphological differentiation is not strongly pronounced, they show marked molecular divergence, suggesting recognition as a new species, Cardamine apennina. Because of their restricted distribution and diploid chromosomal level, C. apennina and C. granulosa may represent basal and quite isolated lineages, whereas reticulation on diploid and polyploid level has affected remaining lineages of the C. pratensis group. Both Italian endemics are endangered due to rarity and habitat loss. A key for identification of the Italian taxa of the C. pratensis group is also provided. 相似文献