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1.
2017年,印度学者Joe等基于采自中国藏东南地区的植物标本,发表了合萼吊石苣苔的一新变种Lysionotus gamosepalus W. T. Wang var.biflorus A. Joe, Hareesh&M. Sabu,并且认为该新变种与原变种的主要区分特征包括叶缘稍具锯齿、每个腋生花序仅有2朵花、花冠被毛、具2枚卷曲的退化雄蕊。然而,近年来,笔者基于查阅大量标本和野外考察工作,认为所谓变种的形态特征是在合萼吊石苣苔(Lysionotus gamosepalus W. T. Wang)的变异范围之内,加之分布区完全重叠,生长环境类似,物候期一致,不宜作为变种等级处理。故在此将该变种处理为合萼吊石苣苔的异名。  相似文献   

2.
为理清芸香科(Rutaceae)九里香属(Murraya)中大叶九里香[M. kwangsiensis (C. C. Huang)C. C. Huang var. macrophylla C. C. Huang]与其原变种广西九里香[M. kwangsiensis(C. C. Huang)C. C. Huang var. kwangsiensis]间的系统关系及其分类学地位,采用综合文献查阅、标本鉴定、野外实地调查、栽培观察及显微解剖等多种方法对九里香属植物数个种类进行分类学相关研究。结果发现:大叶九里香在叶片、花、果实等形态特征方面与广西九里香间的差异极大,故将其处理为一个独立的种,并提出新等级组合Murraya macrophylla (C. C. Huang)F. J. Mou; 首次对大叶九里香的形态特征及分布进行详尽描述; 该物种的羽状复叶及小叶均为九里香属中最大者,更接近仅分布于越南的光叶九里香[M. glabra (Guillaumin)Swingle],但其较大的小叶、叶面叶脉下凹且叶片皱缩等特征使其明显不同于九里香属其他种类。大叶九里香是一个独立种而非广西九里香的变种,此关于大叶九里香分类地位的新观点有助于整个九里香属的系统发育关系重建及种间系统关系的深入探索。  相似文献   

3.
A revision of Brazilian Augusta and general comments on the systematics of this genus are presented. The complex taxonomic history of this taxon has caused confusion over its correct nomenclature. The peculiar geographic distribution of Augusta has stimulated field observations and analysis of the ecology of the Brazilian ecosystems where this taxon occurs, which are here presented. The five Brazilian species of Augusta described by Pohl are here treated as ecotypes of A. longifolia. This species has two distinct varieties: var. Longifolia, widespread throughout the Brazilian cerrado, and var. parvifolia, endemic to the Atlantic forest near Rio de Janeiro. Typification, list of representative specimens, and distribution map of A. longifolia are also included.  相似文献   

4.
Several taxonomic problems of KoreanSmilacina were examined by statistical methods, based on morphological data. Consequently,S. davurica described in Korean flora differs greatly from originalS. davurica, and closely related toS. bicolor morphologically. Therefore, the present authors treated this new taxon as a variety ofS. bicolor, S. bicolor var.flavovirens N. S. Lee et J. Y. Kim var. nov (“Yondusomdae” in Korean). The distribution in South Korea ofS. bicolor var.bicolor is known as only Mt. Chiri, but this species is collected in Mt. Dukyou, also. The bounds of morphological variations ofS. japonica var.japonica, the short plant size and no hairs on the stem, were revealed. The morphological characteristics ofS. japonica var.japonica andS. japonica var.mandshurica is obscure to distinguish. According to the present study,S. japonica var.mandshurica differs fromS. japonica var.japonica in plant size, size of adaxial leaf epidermal cell, ratio of style/ovary length and shape of stigma. The unrecorded taxon in Korean flora,S. robusta, was given a new Korean name as “Kunsomdae.” AlthoughS. japonica var.mandshurica is the variety ofS. japonica var.japonica, it is more closely related toS. robusta than toS. japonica var.japonica.  相似文献   

5.
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   

6.
A phylogenetic analysis of all the intrageneric taxa of the genus Dioon Lindley (Zamiaceae) was undertaken by using chloroplast DNA restriction fragment length polymorphism analysis. Wagner parsimony analysis on a 187 character matrix yielded two equally parsimonious trees, differing only for the position of D. caputoi. The consensus tree has two well-defined major clades. The first is composed of D. mejiae, D. rzedowskii, and D. spinulosum; the second is composed of D. califanoi, D. caputoi, D. edule var. angustifolium, D. edule var. edule, D. holmgrenii, D. merolae, D. purpusii, D. tomasellii var. sonorense, and D. tomasellii var. tomasellii. A phenetic analysis of the same data showed results broadly congruent with the cladistic analysis. This resulting phylogeny is partially congruent with morphological data and is also compatible with the biogeography of the genus. Modem species of Dioon may have evolved as a consequence of a very fast succession of vicariance events that mainly occurred during the early Cenozoic. The short time between each of these events may not have allowed the accumulation of a large number of morphological synapomorphies for the groups of species.  相似文献   

7.
The genus Coelastrella was established by Chodat (Bull. Soc. Bot. Geneve, 13 [1922] 66), and was characterized as being unicellular or in few‐celled aggregations with many longitudinal ribs on the cell wall. Many species of this genus showed strong ability to accumulate carotenoids and oils, so they have recently attracted much attention from researchers due to its potential applicability in the energy and food industries. In this study, a total of 23 strains of Coelastrella were sampled from China, and three new species and two new varieties were described: C. thermophila sp. nov., C. yingshanensis sp. nov., C. tenuitheca sp. nov., C. thermophila var. globulina var. nov., C. rubescens var. oocystiformis var. nov. Besides 18S rDNA and ITS2 sequences, we have newly sequenced the tufA gene marker for this taxon. Phylogenetic analysis combined with morphological studies revealed four morphotypes within the Coelastrella sensu lato clade, which contained the morphotype of original Coelastrella, original Scotiellopsis, Asterarcys, and morphotype of C. vacuolata and C. tenuitheca sp. nov. The relationships between morphological differences and phylogenic diversity based on different markers were discussed. Our results support that 18S rDNA was too conserved to be used a species‐specific or even a genus‐specific marker in this clade. The topology of tufA gene‐based phylogenetic tree had a better match with the morphological findings.  相似文献   

8.
Taxonomic treatment of the achlorophyllous monotropoid plant Monotropastrum humile is still unclear and confusing because of the lack of detailed morphological analyses and molecular phylogeny. In particular, the taxonomic status of a glabrous variety, M. humile var. glaberrimum, is under debate. Our detailed examination of the morphological characteristics of living plants revealed that M. humile var. glaberrimum can be easily distinguished from the putative conspecific taxon M. humile var. humile by characteristics not previously recognized, namely the shape and color of the floral disc. Most morphological features characterizing Cheilotheca were also found in M. humile var. glaberrimum. Moreover, there was considerable nucleotide differentiation in the internal transcribed spacer (ITS)2 sequences of M. humile var. humile and var. glaberrimum. Molecular analysis of the phylogenetic relationship of M. humile var. humile, var. glaberrimum, and other monotropoids using ITS2 sequences showed that two varieties of M. humile formed a monophyletic clade with a member of a different genus, Monotropa L., but obvious phylogenetic relationships among these three taxa were not obtained. Thus we conclude that Monotropastrum humile var. glaberrimum should be treated as a distinct species. However, the generic affiliation of M. humile var. glaberrimum could not be determined because of its intermediate character state combination and the insufficient characterization of related species. We strongly suggest that Monotropastrum as a whole needs re-evaluation.  相似文献   

9.
菱科(Trapaceae)仅菱属(Trapa L.)1属,该属是典型的水生多型植物,中国乃至全球以往的分类处理分歧很大。基于文献查阅、野外采集、标本鉴定和栽培观察,对菱属植物分类的主要形态性状作了系统评价。果体大小和果冠变异稳定,可以用于属内种的划分,果喙大小和角的数目则可以用于种下变种的划分。在此基础上,对中国菱属作了分类处理,承认了细果野菱(T. incisa)和欧菱(T. natans)2个种,并将欧菱划分为6个变种,对其中4个变种作了新的组合。将10个种名和12个变种名处理为异名,并对5个名称(Trapa amurensis,T. bispinosa,T. dimorphocarpa,T. japonica,T. manchurica)作了后选模式标定。  相似文献   

10.
Eight taxa in Verbena have been taxonomically difficult (B. bipinnatifida, V. bipinnatifida var. latilobata, V. Wrightii, V. ciliata, V. ciliata var. longidentata, V. ciliata var. pubera, V. ambrosifolia, and V. ambrosifolia f. eglandulosa). The taxonomic difficulties have been suggested to be the result of widespread hybridization. A flavonoid study of the populations belonging to these eight taxa, combined with a morphological survey resulted in the recognition of four taxa, Glandularia bipinnatifida var. bipinnatifida, G. bipinnatifida var. brevispicata, G. Wrightii, and G. chiricahensis. Hybridization is not responsible for widespread variation in this group.  相似文献   

11.
A pea rust fungus, Uromyces viciae-fabae, has been classified into two varieties, var. viciae-fabae and var. orobi, based on differences in urediniospore wall thickness and putative host specificity in Japan. In principal component analyses, morphological features of urediniospores and teliospores of 94 rust specimens from Vicia, Lathyrus, and Pisum did not show definite host-specific morphological groups. In molecular analyses, 23 Uromyces specimens from Vicia, Lathyrus, and Pisum formed a single genetic clade based on D1/D2 and ITS regions. Four isolates of U. viciae-fabae from V. cracca and V. unijuga could infect and sporulate on P. sativum. These results suggest that U. viciae-fabae populations on different host plants are not biologically differentiated into groups that can be recognized as varieties.Contribution no. 184, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan  相似文献   

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14.
A micro‐morphological analysis of leaf epidermis (adaxial and abaxial sides) of fifteen taxa of Carex section Phacocystis was carried out using light microscopy and scanning electron microscopy (SEM). Three taxa were epistomatic (C. nigra var. nigra, C.nigra var. juncea and C. subspathacea), seven taxa were hypostomatic (C. acuta, C. bigelowii ssp. bigelowii, C. bigelowii ssp. rigida, C. cespitosa, C. elata, C. lyngbyei and C. paleacea) and five amphistomatic (C. aquatilis, Chalophila, C. rufina, C. stans and C. trinervis). Epidermal modifications such as prickles were present in many species. The micro‐morphological leaf characters of the investigated species were found to be important for distinguishing individual taxa but not for subsectional classification.  相似文献   

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The grain amaranths (Amaranthus hypochondriacus, A. caudatus and A. cruentus) have a long history and a unique process of domestication. They are supposedly derived from a weed progenitor. The hypothesis proposing a monophyletic origin of the grain amaranths from the close relative A. hybridus is widely favoured. The present study applied morphological and biochemical tools, and revealed a close affinity between A. hypochondriacus and A. caudatus, and a distinct divergence of A. cruentus from the others, in accordance with previous observations. Accessions of A. cruentus showed a prominent variability, especially in seed surface features, which strongly proposed a segregation of the population into two groups; one having rusty brown seeds with reticulate spermoderm and another group having greyish white seeds with rugulate spermoderm: Amaranthus cruentus var. albus var. nov. and Amaranthus cruentus var. cruentus var. nov. This introduction was well supported by cluster analysis, showing a clear delimitation of brown and greyish white seeded accession of A. cruentus.  相似文献   

19.
A new halophilous–gypsicolous species of Corynopuntia, C. halophila (Cactaceae), is described and illustrated from the state of Coahuila, north-eastern Mexico. It is morphologically similar to the diploid Corynopuntia moelleri, but it differs by some traits, such as body size and some unusual morphological features which are here reported for the first time; there are also ecological and karyological differences, as the latter study revealed that C. halophila is a polyploid with 2n = 44 chromosomes. Diagnostic morphological characters from similar taxa are discussed and arranged in a taxonomic key. Knowledge of the species ecology, biogeography, demography and conservation status is also provided.  相似文献   

20.
Chloroplast DNA restriction site variation of ten endonucleases was examined among all ten species or varieties of the eastern Asia–eastern North America disjunct section Rytidospermum of Magnolia. Representatives from seven of the other ten sections of Magnolia and four related genera (Liriodendron, Manglietia, Michelia, and Talauma) were also included in the survey. A cladistic analysis of 200 variable sites using Wagner parsimony yielded 11 equally most parsimonious trees with a consistency index of 0.793 and a retention index of 0.870. The section Rytidospermum is polyphyletic in these trees. Magnolia tripetala from the southeastern U.S. is the only American species that has a sister relationship to the Asian taxa, M. hypoleuca, M. officinalis var. officinalis, M. officinalis var. biloba, and M. rostrata. Other American taxa in the section fall into two lineages, with M. macrophylla var. macrophylla, M. macrophylla var. ashei, and M. macrophylla var. dealbata in one, and M. fraseri var. fraseri and M. fraseri var. pyramidata in the other. They are not related to the Asian species as previously believed. The relationships revealed here are in agreement with morphological, allozymic, and cross compatibility data. These results demonstrate that a robust phylogenetic hypothesis is an important prerequisite for understanding biogeographic patterns.  相似文献   

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