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 31 毫秒
1.
Reports of 89 new counts are recorded for the tribe Helenieae, including reports for 28 genera and 56 species. One genus, Hypericophyllum (n = 9), and six other taxa were previously unreported.  相似文献   

2.
巴西是全球生物多样性最丰富的地区,其竹类多样性也极为丰富。结合现存资料及野外调查,对巴西全境的竹类分布格局进行了讨论。巴西全国有原生竹亚科植物256种(含2亚种及3变种),北部地区草本竹类(莪莉竹族)最丰富,有61种,而东南部地区木本竹类(箣竹族)最丰富,有96种。偏穗竹属(Merostachys)(43种)和丘斯夸竹属(Chusquea)(45种)是最常见的属,并是最具潜在经济利用的竹类。属种的特有性分别高达32.4%和68.8%。特有属有11个,分别为莪莉竹族的双药莪利草竹属(Diandrolyra)、独焰草竹属(Eremitis)、小百瑞草竹属(Parianella)、赖茨草竹属(Reitzia)、苏克蕾草竹属(Sucrea)和箣竹族的南美梨藤竹属(Alvimia)、离枝竹属(Apoclada)、密穗竹属(Athroostachys)、卡姆巴珠瓦竹属(Cambajuva)、菲尔盖拉斯竹属(Filgueirasia)、无枝竹属(Glaziophyton)。  相似文献   

3.
The present investigation on the axial nodes of 32 taxa belonging to the genera Chara, Lamprothamnium, Nitellopsis, Nitella and Tolypella confirms previous reports that within a given taxonomic group the structure of the main axial nodal complex is highly consistent. Besides the genera Nitella and Tolypella of the tribe Nitelleae, Lamprothamnium of the tribe Chareae is the only genus in which the central cells of the main axial nodal complex subdivide. This anatomical feature of the main axial nodal complex thus clearly separates the genus Lamprothamnium from the other genera of the tribe chareae. In 2 controversial species of the genus Chara, C. hornemannii and C. buckellii, the present study reveals that the central cells of their main axial nodal complexes do not subdivide. The transfer of these two species to the genus Lamprothamnium by Daily (1) may not be appropriate.  相似文献   

4.
The pollen morphology of 9 of the 11 genera of the tribe Swartzieae is described together with that of Holocalyx and Cyathostegia, two genera recently removed from the tribe based on macromorphology. The pollen is small, spheroidal to subprolate, primarily tricolporate with a perforate tectum and generally typical of the Leguminosae. Nonetheless, many of the genera have distinctive pollen morphology. Baphiopsis is 6-colporate. The genera Harleyodendron, Lecointea and one species of Exostyles have supratectal spinules. Bocoa viridiflora has striate/rugulate ornamentation very distinct from the other species of the genus Bocoa. The exine stratification is varied but Candolleodendron has a very thick endexine and narrow foot layer. The pollen of African taxa does not differ significantly from that of South American taxa. Pollen morphology does not clarify the taxonomic relationships of the tribe and provides little evidence to assist in positioning Holocalyx and Cyathostegia.  相似文献   

5.
天门冬科黄精族细胞学研究进展   总被引:1,自引:0,他引:1  
在全面收集和整理黄精族染色体数据的基础上,对国内外有关黄精族各类群间的染色体数目和倍性的变化规律进行了总结,并从染色体的多倍化和非整倍化与系统发育关系和地理分布方面探讨了黄精族内各属的起源和演化关系问题。黄精族包括黄精属、舞鹤草属、异黄精属和竹根七属,共约100余种,其中舞鹤草属(x=18)、异黄精属(x=16)和竹根七属(x=20)的染色体基数稳定,而黄精属染色体基数波动较大,主要为x=8~16,既有多倍化也有非整倍化现象。染色体数据表明黄精族4个属的染色体进化模式各不相同,揭示了黄精族内染色体从高基数向低基数演化的规律;各属内染色体的演化主要是体现在二倍体水平上的核型变异,多倍化在本族中不占主导地位;仅黄精属内伴有非常强烈的非整倍化现象;细胞学证据与分子系统发育的结果比较吻合,为黄精族内属间以及属下的系统发育与进化提供了重要的参考资料。  相似文献   

6.
Ornduff , Robert (Duke U., Durham, N. C), Peter H. Raven , Donald W. Kyhos , and A. R. Kruckeberg . Chromosome numbers in Compositae. III. Senecioneae. Amer. Jour. Bot. 50(2): 131–139. Illus. 1963.—Chromosome counts are reported for 75 taxa of tribe Senecioneae (Compcsitae) and are listed with a generic summary of previous counts in the tribe. First counts are reported for Bedfordia, Crocidium, Dimeresia, Gamolepis, Lepidospartum, Luina, Peucephyllum, Telradymia, and the first definite count recorded for Euryops. New numbers are added to those previously known in Arnica and Psathyrotes. Intraspecific differences in ploidy-level are reported in 4 North American species of Senecio. Although chromosome numbers are useful as an aid in delimiting some genera of Senecioneae, they are of little use in circumscribing genera peripheral to Senecio, primarily because of the great range of chromosome numbers of that genus. Chromosome numbers support suggestions based on morphological considerations that genera such as Crocidium and Dimeresia do not belong in Senecioneae, whereas chromosome number and morphology of the plants virtually prohibit the removal of such genera as Peucephyllum, Lepidospartum, and Telradymia from Senecioneae, despite the suggestions of several recent authors. It is proposed that the base number for the tribe is 10 and that the tribe originated in the Old World, with subsequent widespread migration and diversification.  相似文献   

7.
A total of 56 morphological characters were analyzed for 53 cirrospiline species that represent all of the 17 described genera of the tribe. The other taxa of the Eulophinae included in the analysis were six species of six representative genera in the tribe Eulophini, a species of Elasmus (the only genus comprising the tribe Elasmini), and a species of Trichospilus (unplaced). Trichospilus and two of the six genera of Eulophini examined were placed within Cirrospilini. Monophyly of Cirrospilini (when these two genera of Eulophini and Trichospilus are included) and of the cirrospiline genera for which more than one species were examined was supported, but the relationships between the genera were poorly resolved. An exception was Cirrospilus, the largest genus in the Cirrospilini, monophyly of which was not supported to any extent.  相似文献   

8.
Phylogenetic analyses of 33 genera of Rubiaceae were performed using morphological and a few chemical characters. Parsimony analysis based on 29 characters resulted in eight equally parsimonious trees, with a consistency index of 0.40 and a retention index of 0.69. These results were compared to a phylogenetic analysis of the same genera based on chloroplast DNA restriction site data. There are discrepancies between the two analyses, but if we consider groupings reflected in the present classification there is much congruency. With the exception of four genera, all the genera are positioned in the same group of taxa in the two analyses. Clades of taxa representing three of the four subfamilies (~the Antirheoideae, ~the Rubioideae, and the ~Ixoroideae) are monophyletic, while the fourth subfamily Cinchonoideae is shown to be paraphyletic. Both analyses support a widened tribe Chiococceae, including the former subtribe Portlandiinae (Condamineeae). Furthermore, in both analyses the tribe Hamelieae is placed outside the subfamily Rubioideae where it is now housed. In search for the most plausible sister group to the Rubiaceae, the genus Cinchona (Rubiaceae) was analyzed together with 13 genera of the Loganiaceae, Nerium (Apocynaceae), and Exacum (Gentianaceae). Cornus (Comaceae), Olea (Oleaceae), and these two genera together were used as outgroups. The analysis, including 25 characters, 16 taxa, and with Cornus and Olea together as an outgroup, resulted in four equally parsimonious trees, with a consistency index of 0.53 and a retention index of 0.62. The non-Loganiaceae taxa Cinchona (Rubiaceae), Nerium (Apocynaceae), and Exacum (Gentianaceae) were all found to have their closest relatives within the Loganiaceae indicating that the Loganiaceae are paraphyletic and ought to be reclassified. As a result of the morphological data the most plausible sister group to the Rubiaceae is the tribe Gelsemieae of the Loganiaceae.  相似文献   

9.
L. Cecchi  F. Selvi 《Plant biosystems》2013,147(4):630-677
A synopsis of the Italian taxa of tribe Boragineae (Boraginaceae, subfam. Boraginoideae) is given as a second contribution to the treatment of the family for the Flora Critica d'Italia project. The work is mainly based on the critical study of herbarium material and extensive literature survey. All relevant floristic reports were examined and types of all the accepted (51) and most (37/46) of the synonymized names of taxa, specific and infraspecific, reported from the National territory are indicated. In the light of karyological and morphological evidence, the new combination Pulmonaria vallarsae subsp. apennina is proposed. As a result, 12 genera and 37 species are recognized, of which 7 are allochtonous and 6, plus two subspecies, are endemic. A synthetic floristic treatment is provided, including analytical keys, hybrids, list of synonyms and short distribution notes. In addition, detailed distribution maps are provided, together with the lists of the selected specimens upon which they are based.  相似文献   

10.
Phrygionis and Pityeja belong to the Palyadini, a tribe of neotropical Ennominae. The moths of both genera bear striking wing markings and mere variants were frequently described as species with the consequence that species diversity was overestimated. Numerous taxonomic changes are made in this work based on the study of primary types and much other material. Variation and distribution is recorded for each species and subspecies. Phylogenetic relationships within Phrygionis are examined, and comments are made on the evolution of wing pattern within this genus.
Fifteen full species are recognized in this study (13 in Phrygionis and two in Pityeja ), of which four (all in Phrygionis ) are described as new; 19 species-group (specific and subspecific) names refer to valid taxa. Twenty-four species-group names are synonymized (19 in Phrygionis and five in Pityeja ) and five are recombined with different genera (four with Phrygionis and one with Pityeja ). Three generic names are synonymized (one in Phrygionis and two in Pityeja ).  相似文献   

11.
Chromosome numbers for 16 different taxa ofRubiaceae from Sri Lanka are presented. Counts for 13 species, including 5 genera and 1 tribe, are new. The results are listed, compared with available literature data and discussed in regard to their systematical importance.  相似文献   

12.
The stonefly genus Siphonoperla Zwick, 1967 (Chloroperlidae) ranges from the Atlas Mountains of North Africa, throughout Europe and east to the Lesser Caucasus Mountains in Armenia. Systematic relationships within the genus are unknown. We provide the first molecular phylogenetic reconstruction of the genus, based on sequence variation of 1348 bp of the mitochondrial cytochrome c oxidase subunit I gene and relate this phylogeny to a few key morphological features as well as zoogeographical perspectives. A total of 15 taxa (32 individuals), including four outgroup species (Chloroperla Newman, 1836 and Xanthoperla Zwick, 1967 ) were screened. Monophyly of Siphonoperla, as well as each purported taxon was supported, with net pairwise distances ranging from 0.7% to 13.7%. Within‐taxon variability ranged from 0% to 6.2%, whereby the upper value relates to Siphonoperla torrentium Pictet, 1841 represented in our sample by three allopatric subspecific taxa. These taxa, displayed as a polytomy with an estimated time to the most recent common ancestor of about 5.4 Myr, are also shown to have distinct genitalia. These data could be used to support a species‐level distinction for the three subspecific taxa. Siphonoperla ranged from 13% (Xanthoperla) to 16.2% (Chloroperla) divergent from the outgroup genera. The recently described Siphonoperla ottomoogi, Graf, 2008 from Austria is not closely related to the sympatric Siphonoperla montana Pictet, 1841 and is a minimum of 7.8% divergent from congenerics, supporting its status as a micro‐endemic relict surviving on the edge of Alpine glaciation throughout the Pleistocene. Overall, the genus shows the highest levels of diversification in the Mediterranean and Southeast regions whereby at least some of the species found in Central Europe today may have persisted there in peri‐glacial refugia throughout the Pleistocene.  相似文献   

13.
This study includes 24 reports of chromosome counts in Tripleurospermum Sch. Bip. (20 taxa), Anthemis L. (1 species) and Matricaria L. (3 taxa) belonging to the tribe Anthemideae of the family Asteraceae from Turkey. Chromosome numbers of these taxa are 2n = 2x = 18, 3x = 27 and 4x = 36. Nine counts are new reports, one is not consistent with previous report, and the remainder confirm earlier information. Statistically significant differences depending on ploidy level, stomatal length or environmental factors such as altitude were determined in Tripleurospermum. Several systematic and evolutionary aspects of the genera are discussed in the light of chromosomal data.  相似文献   

14.
Sister‐group relationships are resolved for the systematically and biogeographically puzzling austral rove beetle genus Hyperomma by means of phylogenetic analysis of five gene markers (one mitochondrial and four nuclear protein‐coding) for 25 taxa broadly representing the subfamily Paederinae, and six outgroup taxa from Staphylininae and Pseudopsinae. As a result, the new subtribe Dicaxina subtrib. nov. is established for Hyperomma and five other Southern Hemisphere genera previously classified in Cryptobiina. Based on the molecular phylogeny and the discussion of several adult and larval morphological characters, the concept of the tribe Paederini is changed as follows: Paederini sensu novo is reduced to include Paederina, Cryptobiina, Dolicaonina and Dicaxina only, while Lathrobiini sensu novo is established for Lathrobiina, Scopaeina, Astenina, Stilicopsina, Medonina, Stilicina and Echiasterina. The tribe Cylindroxystini stat. resurr. is reinstated for the Paederini subtribe Cylindroxystina because of its very peculiar morphology not fitting either Paederini or Lathrobiini in new sense. The tribe Pinophilini was resolved as sister to Lathrobiini sensu novo, and its status remains unchanged. Morphological diagnoses and other relevant systematic information are provided for all newly established taxa. The taxonomic history of the higher‐level systematics of the subfamily Paederinae is summarized.  相似文献   

15.
Phylogenetic relationships within the bee family Megachilidae are poorly understood. The monophyly of the subfamily Fideliinae is questionable, the relationships among the tribes and subtribes in the subfamily Megachilinae are unknown, and some extant genera cannot be placed with certainty at the tribal level. Using a cladistic analysis of adult external morphological characters, we explore the relationships of the eight tribes and two subtribes currently recognised in Megachilidae. Our dataset included 80% of the extant generic‐level diversity, representatives of all fossil taxa, and was analysed using parsimony. We employed 200 characters and selected 7 outgroups and 72 ingroup species of 60 genera, plus 7 species of 4 extinct genera from Baltic amber. Our analysis shows that Fideliinae and the tribes Anthidiini and Osmiini of Megachilinae are paraphyletic; it supports the monophyly of Megachilinae, including the extinct taxa, and the sister group relationship of Lithurgini to the remaining megachilines. The Sub‐Saharan genus Aspidosmia, a rare group with a mixture of osmiine and anthidiine features, is herein removed from Anthidiini and placed in its own tribe, Aspidosmiini, new tribe . Protolithurgini is the sister of Lithurgini, both placed herein in the subfamily Lithurginae; the other extinct taxa, Glyptapina and Ctenoplectrellina, are more basally related among Megachilinae than Osmiini, near Aspidosmia, and are herein treated at the tribal level. Noteriades, a genus presently in the Osmiini, is herein transferred to the Megachilini. Thus, we recognise four subfamilies (Fideliinae, Pararhophitinae, Lithurginae and Megachilinae) and nine tribes in Megachilidae. We briefly discuss the evolutionary history and biogeography of the family, present alternative classifications, and provide a revised key to the extant tribes of Megachilinae.  相似文献   

16.
The phylogenetic relationships of Peniocereus (Cactaceae) species were studied using parsimony analyses of DNA sequence data. The plastid rpl16 and trnL-F regions were sequenced for 98 taxa including 17 species of Peniocereus, representatives from all genera of tribe Pachycereeae, four genera of tribe Hylocereeae, as well as from three additional outgroup genera of tribes Calymmantheae, Notocacteae, and Trichocereeae. Phylogenetic analyses support neither the monophyly of Peniocereus as currently circumscribed, nor the monophyly of tribe Pachycereeae since species of Peniocereus subgenus Pseudoacanthocereus are embedded within tribe Hylocereeae. Furthermore, these results show that the eight species of Peniocereus subgenus Peniocereus (Peniocereus sensu stricto) form a well-supported clade within subtribe Pachycereinae; P. serpentinus is also a member of this subtribe, but is sister to Bergerocactus. Moreover, Nyctocereus should be resurrected as a monotypic genus. Species of Peniocereus subgenus Pseudoacanthocereus are positioned among species of Acanthocereus within tribe Hylocereeae, indicating that they may be better classified within that genus. A number of morphological and anatomical characters, especially related to the presence or absence of dimorphic branches, are discussed to support these relationships.  相似文献   

17.
Reports of 100 new chromosome counts are made for the tribe Astereae of Compositae, mostly based on determinations of meiotic material, including first counts for 9 genera and 53 species. Counts are now available for 58 of the approximately 100–120 genera and 431 of the approximately 2000 species in the tribe. Comparisons are made between chromosome number and habit and also between chromosome number and geographical distribution. Species and genera with a basic number of x = 9 are the most abundant. Within different phyletic lines x = 9 is also the most abundant number. On the other hand, many species with x = 4 and 5, belonging to a number of small, largely annual genera, are concentrated in southwestern North America. The low chromosome number in these plants is probably correlated with the dry habitat they occupy, and is most likely a specialized condition.  相似文献   

18.
Adenocaulon andEriachaenium are two problematic genera because their tribal and subfamilial placement in Asteraceae is uncertain. Previous cladistic analyses based on molecular data undertaken to analyze the relationships within Asteraceae, placeAdenocaulon in the tribe Mutisieae (Cichorioideae). This paper investigates cladistic relationships amongAdenocaulon andEriachaenium and tribes of subfamilies Cichorioideae and Asteroideae using morphological data. Thirty-eight characters were scored across 52 genera selected as exemplar taxa to represent the current classification system. In the analysis (one tree, length = 86, c.i. = 0.55, r.i. = 0.64)Adenocaulon andEriachaenium are sister taxa and appear as an isolated clade nested in Cichorioideae. A new, tentative position among the tribes of the paraphyletic Cichorioideae is proposed for these two isolated genera.  相似文献   

19.
Chromosome counts are reported for 76 taxa and 2 natural hybrids of tribe Senecioneae (Compositae). First counts are reported for several species of Senecioneae as well as for the genera Cadiscus and Whitneya. New chromosome numbers are added to those previously known in Arnica, Cacalia, and Senecio. Additional counts from Arnica support our previous suggestion that x = 19 for this genus. It is assumed that observed meiotic irregularities are associated with apomixis in this genus. Basic chromosome numbers for various New World sections of Senecio are proposed, and certain problems of sectional relationships in this genus are discussed. Chromosome numbers and plant morphology of Cadiscus, Hulsea, and Whitneya indicate that these genera should be removed from Helenieae to Senecioneae. The possible affinity of the anomalous genus Adenocaulon with Mutisieae is discussed. Data presented in the paper further support our earlier proposal that the basic chromosome number for Senecioneae is x = 10.  相似文献   

20.
Twenty-two chromosome counts of 19 taxa (21 populations) in the tribe Anthemideae and one member (one population) of the tribe Inuleae of the family Asteraceae are reported. The Anthemideae studied belong to the subtribes Artemisiinae (14 Artemisia taxa, and one species each of the genera Dendranthema , Filifolium and Neopallasia ) and Tanacetinae (one species each of the genera Lepidolopha and Tanacetopsis ). From the Inuleae, we studied one Inula species. Five counts are new reports (including two at generic level), six are not consistent with previous counts and the remainder are confirmations of very limited (one to four records) previous data. Most of populations of Anthemideae studied have the basic chromosome number x  = 9, with ploidy levels ranging from 2 x to 10 x . Dysploidy is also present, with two x  = 8 diploid taxa. The species of Inuleae studied is a diploid with x  = 10, also indicating dysploidy, other members of the same genus Inula having basic numbers of x  = 9 or 8.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 77–85.  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