首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
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   

2.
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.  相似文献   

3.
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   

4.
Intermediates between two South American species ofGrindelia were found in Chubut Province, Argentina. Twenty eight individual plants with phenotypes ofG. brachystephana, G. chiloensis, or intermediates were collected and studied together with three reference specimens of each of the putative parental species. Discriminant analysis procedure and the computer program HYWIN were applied and results of the two methods are compared. Results demonstrate that most of the specimens collected are of hybrid origin, and that most of the specimens suggested as hybrids are most likely introgressants. Hybridization and introgression are likely the major causes of the high variability previously attributed toG. chiloensis by taxonomists.  相似文献   

5.
A new species, Haplopappus graniticus, is described and illustrated. Its relationships seemingly lie with section Tonestus but its narrow heads and imbricated phyllaries are anomalous in that section.  相似文献   

6.
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.
Taxonomic revision of South American species ofGrindelia Willd. has revealed two new species from Uruguay:G. rupestris, an erect subshurb with crowded obovate denticulate leaves, subsessile heads, and pappus composed of numerous awns, andG. linearifolia, a prostrate shrublet with small entire linear leaves. Both species are described and illustrated. A key for the UruguayanGrindelia species is provided.  相似文献   

8.
9.
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   

10.
Townsendia gypsophila, a new species from Sandoval Co., New Mexico, is described and illustrated. It is a narrowly distributed obligate gypsophile closely related toT. fendleri andT. incana. It overlaps the ranges of the two taxa at the edge of their distributional limits in New Mexico.  相似文献   

11.
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   

12.
Rayjacksonia R. L. Hartman & M. A. Lane, gen. nov. (Compositae: Astereae), is named to accommodate the “phyllocephalus complex,” formerly of Haplopappus Cass. sect. Blepharodon DC. The new combinations are R. phyllocephalus (DC.) R. L. Hartman & M. A. Lane, R. annua (Rydb.) R. L. Hartman & M. A. Lane, and R. aurea (A. Gray) R. L. Hartman & M. A. Lane. This transfer completes the reclassification of the North American species of Haplopappus sensu Hall, leaving that genus exclusively South American. Rayjacksonia has a base chromosome number of x = 6. Furthermore, it shares abruptly ampliate disk corollas, deltate disk style-branch appendages, and corolla epidermal cell type, among other features, with Grindelia, Isocoma, Olivaea, Prionopsis, Stephanodoria, and Xanthocephalum. Phylogenetic analyses of morphological and chloroplast DNA restriction site data, taken together, demonstrate that these genera are closely related but distinct.  相似文献   

13.
Carlos Parra-O 《Brittonia》2000,52(4):320-324
Morella chevalieri is described as new and is illustrated; it grows in the Andes in northern Argentina and southern and central Bolivia. A key that differentiates this new species from the monoeciousMyrica pubescens is presented. The dioecious Morella chevalieri is characterized by the following: leaf blade elliptic to narrowly elliptic, margin serrate (at least in the distal 2/3); staminate flowers with one or no secondary bracts (if present, linear or band-shaped) and secondary bracts in the pistillate flower 2–3 (seldom 4).
Resumen  Se describe e ilustra aMorella chevalieri como nueva especie; se distribuye en los Andes de la parte norte de Argentina y de las partes sur y central de Bolivia. Se presenta una clave que diferencia a esta nueva especie de la monóicaMyrica pubescens. La dióica Morella chevalieri se reconoce por los siguientes caracteres: lámina de la hoja elíptica o angostamente elíptica, margen aserrada (al menos en las dos terceras partes distales); flores estaminadas sin o con una bráctea secundaria (esta con forma linear o acintada) y brácteas secundarias de la flores pistiladas de 2 a 3 (raramente 4).
  相似文献   

14.
Solanum homalospermum (Solanum subgen.Leptostemonum) is described and illustrated from central Argentina.Solanum homalospermum is characterized by having heteromorphic gynoecia, strongly flattened seeds, unequal anthers, and gemmiferous roots.  相似文献   

15.
A new species, Klasea yunus-emrei B. Dogan, Ocak & A. Duran (Asteraceae), is described from central Anatolia, Turkey. The species grows on calcareous soils in the Alpu district (Eski¸ehir province) in central Anatolia. It is morphologically similar to Klasea lasiocephala (Bornm.) Greuter & Wagenitz. Diagnostic morphological characters from closely similar taxa are discussed and arranged in a key. Ecology, conservation status and biogeography of the species are also presented. The achene surface of K. yunus-emrei and K. lasiocephala are examined by Scanning Electron Microscope. In addition, the geographical distribution of the new species and other related species are mapped.  相似文献   

16.
Asterchusanensis is described and illustrated, and compared with its most closely related species,A. pseudoglehni andA. spathulifolius. This new species differs markedly from the latter two by its unequal inner and outer phyllaries, pubescent stem, leaves, and corolla tube, and ray florets partly in two series.  相似文献   

17.
Johnsson  R. 《Hydrobiologia》2001,(1):427-430
A new species of Acontiophorus belonging to the family Asterocheridae was found in Ushuaia, Patagonia, southern Argentina. The new species is distinctive in having 9-segmented antennule, five setae on terminal endopodal segment of leg 1, seven elements on terminal segment of leg 1 and leg 4 exopods, and characteristic setation on maxillule lobes. This combination of characteristic features does not occur in any other species of the genus. The genus Acontiophorus is recorded for the first time from the South Atlantic.  相似文献   

18.
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   

19.
该文描述了江西东北部菊科兔儿风属一新种——婺源兔儿风(Ainsliaea wuyuanensis Z.H.Chen,Y.L.Xu et X.F.Jin),并附有线描图和彩色照片。婺源兔儿风是密聚组(Sect.Aggregatae Beauv.)一个非常特殊的种,与本组的其他种类区别很大。从叶脉类型来看与粗齿兔儿风(A.grossedentata Franch.)比较接近,区别在于其叶片较大,菱形或菱状卵形,长11~17 cm,顶端渐尖,基部楔形,叶缘中上部具1~2对裂片状粗大锯齿,两面无毛;叶柄长2~14 cm;总苞片顶端锐尖;瘦果较长,密被污黄色糙毛。  相似文献   

20.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号