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1.
Holcus mollis L. subsp. hierrensis is new to science. Its distinct chamaephytic habit and particular features of the morphology of the spikelets, provided in a key, as well as its ecology allow a taxonomic separation from the otherwise similar subsp. mollis. A short survey of important facts about the species given in the literature is presented. The possible status of the new subspecies as a neoendemic of the island of El Hierro (Canaries) is discussed.  相似文献   

2.
The morphology, phenology and allozyme polymorphism in seven tetraploidDactylis glomerata populations growing in the French Alps were studied. Based on habitat and morphological characteristics, two of the populations could be classified asD. glomerata subsp.reichenbachii, which is known to comprise diploid and tetraploid plants growing exclusively on dolomite, on south-facing meadows. This subspecies has been previously recorded in the Italian and Swiss Alps but not in the French Alps. The remaining five populations were morphologically intermediate but more similar to the cosmopolitanD. glomerata subsp.glomerata. On the basis of allozyme variation, all populations were more related to subsp.reichenbachii than to the cosmopolitan subsp.glomerata, suggesting that gene flow has occurred between the two tetraploid subspecies. The possibility that selection has acted differently on morphological and allozyme characters is discussed.  相似文献   

3.
A new subspecies, Klasea serratuloides (DC.) Greuter & Wagenitz subsp. karamanica B. Dogan & A. Duran (Asteraceae), is described and illustrated from Anatolia, Turkey. The subspecies grows on stony places in the Ayranc? and Ermenek district (C4 Karaman Province), Ere?li district (C5 Konya province) and Uluk??la (C5 Ni?de province) in the central and south Anatolia transition zone. It is morphologically similar to K. serratuloides subsp. serratuloides. Diagnostic morphological characters from closely similar taxa are discussed and arranged in a key. Ecology and conservation status of the subspecies is also presented. In addition, the geographical distribution of the new subspecies and other related species is mapped. The pollen morphology and achene surface of K. serratuloides subsp. karamanica and K. serratuloides subsp. serratuloides were examined by SEM.  相似文献   

4.
 In samples from 56 populations of Cardamine amara, representing four diploid subspecies (subspp. amara, opicii, balcanica, and pyrenaea) and two tetraploid subspecies (subspp. austriaca and olotensis) from different parts of the European distribution area, four enzyme systems with 23 alleles were studied. These data, together with previous morphological and karyological data, suggest that the distribution and variation pattern within the species was strongly influenced by the last glacial period and postglacial migrations. Cardamine amara subsp. pyrenaea is monomorphic for a unique allele, and subsp. balcanica has a unique allele, too which, however, is not fixed in all populations of the taxon. Both taxa seem to be relic ones, although otherwise subsp. balcanica in respect of allelic spectrum much resembles subsp. amara. The other two diploid subspecies, subsp. amara and subsp. opicii, are not characterised by presence of unique alleles but differ in allele frequencies. The two tetraploid subspecies have different evolutionary histories. C. amara subsp. austriaca seems to be an autopolyploid derivative of subsp. amara which colonised open space offered by retreating glaciers in the Eastern Alps. C. amara subsp. olotensis from the Iberian Peninsula represents most probably a polyploid of preglacial time. Received June 22, 2001; accepted May 17, 2002 Published online: September 13, 2002  相似文献   

5.
Stachys recta L. is a very polymorphous species in which numerous subspecies were recognised. S. recta L. subsp. serpentini (Fiori) Arrigoni is a typical endemism growing on serpentine soils in northern Apennines and particularly in Tuscany (Italy). In order to contribute to a better knowledge of this plant and to its differentiation with respect to S. recta L. subsp. recta, the micromorphological characters (non-glandular and glandular trichomes) and the essential oil composition of the two subspecies were investigated. Micromorphological characters were studied using scanning and transmission electron microscopy, while light microscopy was used for histochemical observations. Essential oil analysis was carried out by gas chromatography and mass spectrometry.In the two examined taxa, the morphology and distribution of glandular and non-glandular trichomes, and the different essential oil composition, may be considered distinctive characters at subspecies level. This is consistent with the taxonomic classification considering S. recta subsp. serpentini a subordinate taxon of S. recta.  相似文献   

6.
The carnivorous wetland plant, Sarracenia purpurea (the northern pitcher plant) is native to eastern and Midwestern North America. This species is abundant within its habitat but suitable habitat is increasingly scarce, raising interest in S. purpurea restoration and conservation. Complicating conservation planning, two controversial subspecies of S. purpurea are historically defined primarily on morphologic traits: S. purpurea subsp. purpurea distributed north of Maryland and S. purpurea subsp. venosa distributed south of Maryland. S. purpurea is also found in three distinct habitat types defined by substrate: acidic Sphagnum peatlands, acidic sandy savannahs, and alkaline marl wetlands. In species level studies, S. purpurea leaves have exhibited morphological plasticity in response to environmental variability, bringing into question the validity of subspecies definitions based on morphology alone. This study examined morphologic and genetic variation throughout S. purpurea’s natural distribution, encompassing both the traditional subspecies and three unique habitat types testing the validity of traditional subspecies definitions. Genetic analysis indicated possible ecological significance of considering a new grouping of S. purpurea populations into Midwest, N. East Coast and S. East Coast populations (AMOVA % variation = 13.34, P = 0.0078) based on genetic differentiation. Morphological variation in leaf shape measurements supported this division as well as indicating plasticity associated with environmental variables. This study conservatively suggests that new, geographical area conservation units may be a more important conservation unit for preserving S. purpurea genetic variation and morphological plasticity than traditional subspecies definitions.  相似文献   

7.
Coleochloa setifera (Ridl.) Gilly subsp. glabrescens Hoenselaar & D. A. Simpson, a new subspecies from Kenya, is described and illustrated.  相似文献   

8.
9.
Petunia axillaris occurs in temperate South America and consists of three allopatric subspecies: axillaris, parodii, and subandina. Previous studies have revealed that subsp. axillaris is self-incompatible (SI), subsp. parodii is self-compatible (SC) in Uruguay, and subsp. subandina is SC in Argentina. The SI/SC status over the entire distribution range is not completely understood, however. The objective of this study was to examine the overall SI/SC status of the respective subspecies in comparison with floral morphology. The results confirmed that subsp. parodii and subsp. subandina were SC throughout the distribution range, and that subsp. axillaris was also SC in Brazil and in most of the Argentinean territory. The SI P. axillaris occurs in the natural population only between 34 and 36°S, along the eastern shore of South America. The Brazilian and Uruguayan subsp. axillaris differed in SI/SC status and floral morphology. We discuss the cause of this difference.  相似文献   

10.
11.
The grass snake (Natrix natrix) is Europe's most widely distributed and, in many regions, most common snake species, with many morphologically defined subspecies. Yet, the taxonomy of grass snakes is relatively little studied and recent work has shown major conflicts between morphologically defined subspecies and phylogeographical differentiation. Using external morphology, osteological characters, and information from 13 microsatellite loci and two mitochondrial markers, we examine differentiation of the subspecies N. n. astreptophora from the North African Maghreb region, the Iberian Peninsula and neighbouring France. According to previous studies, N. n. astreptophora corresponds to a deeply divergent mitochondrial clade and constitutes the sister taxon of all remaining grass snakes. In the French Pyrenees region, there is a contact zone of N. n. astreptophora with another subspecies, N. n. helvetica. Our analyses of microsatellites and mitochondrial DNA reveal that the distribution ranges of the two taxa abut there, but both hybridize only exceptionally. Even though many morphological characters are highly variable and homoplastic in grass snakes, N. n. astreptophora differs consistently from all other grass snakes by its reddish iris coloration and in having significantly fewer ventral scales and another skull morphology. Considering further the virtual absence of gene flow between N. n. astreptophora and N. n. helvetica, and acknowledging the morphological distinctiveness of N. n. astreptophora and its sister group relationship to all remaining subspecies of grass snakes, we conclude that Natrix astreptophora (Seoane, 1884) should be recognized as a distinct species. Further research is needed to explore whether N. astreptophora is polytypic because a single sample of N. astreptophora from Tunisia turned out to be genetically highly distinct from its European conspecifics.  相似文献   

12.
In the framework of our studies on Lamiaceae from the eastern Iberian Peninsula, for the forthcoming fourth volume of Flora valentina, a new infraspecific arrangement is proposed here for the Iberian endemic Teucrium thymifolium. Besides the type subspecies, T. thymifolium subsp. thymifolium, which is widely distributed through the eastern Iberian Peninsula, two new nomenclatural combinations are established: (i) T. thymifolium subsp. fraternum (Pau) M.B. Crespo, M.A. Alonso & Mart.-Azorín (= T. terciae), for the thermophilous populations growing in SE Murcia province, and (ii) T. thymifolium subsp. hervieri (Briq. & Debeaux) M.B. Crespo, M.A. Alonso & Mart.-Azorín, for Subbaetic inland populations from where the provinces of Albacete, Jaén and Granada come into contact. Nomenclatural types and data on distribution and ecology are reported for all accepted subspecies, including the designation of a lectotype for T. thymifolium subsp. hervieri. Furthermore, relationships of the latter to the recently described T. moleromesae Sánchez Gómez et al. are briefly discussed, both taxa being treated here in synonymy.  相似文献   

13.
For a clearer distinction between the four subspecies of Daucus carota native from Portugal (subsp. carota, subsp. maximus, subsp. gummifer and subsp. halophilus), morphological features of the fruits, DNA content analyses by flow cytometry, and chemical characterization of the essential oils were undertaken.We found chemotaxonomic evidences to consider D. carota subsp. maximus as a separate species rather than a subspecies of D. carota. This separation is based on the morphometric analysis of the fruits and in the high levels of asarone present only in the essential oil of the subsp. maximus. The remaining subspecies are difficult to distinguish from each other based on the morphology of the fruits and in DNA content. However, based on the essential oils, it was possible to distinguish the subspecies halophilus from the other two (subsp. gummifer and subsp. carota) because of its high content of elemicin, with the other two having high levels of geranyl acetate.Based on these results, the subspecies maximus is proposed as a different species (Daucus maximus Desf.) and the taxonomic status of other three subspecies (subsp. carota, subsp. gummifer and subsp. halophilus) is maintained. Still, the latter three taxa need to be further studied for a more precise taxonomic characterization.  相似文献   

14.
Ya Tang  Jia-Sui Xie  Hui Sun 《Flora》2007,202(3):209-217
Pedicularis is one of few genera for which pollination ecology has been studied extensively. Although over half of the species of Pedicularis are found in the mountains of southwestern China, pollination ecology has been studied there on a few species only. The present paper reports pollination ecology of Pedicularis rex subsp. lipskyana and P. rex subsp. rex from Sichuan, southwestern China. The two subspecies are nectariferous, with sugar content 28% in P. rex lipskyana and 22% in P. rex, respectively. The flowers of the two subspecies are adapted to pollination by bumblebee workers. Bumblebees are the primary and effective pollinators although honeybees were also observed pollinating P. rex subsp. lipskyana at one studied population. Usually bumblebees entered the corolla tube from the right side in an upright or a nearly half-inverted position to imbibe nectar located at the base of the corolla tube. The stigma usually contacts the side region of the thorax and abdomen or occasionally directly contacted pollen loads, leading to pollination of flowers. Much less commonly, bumblebees foraged on flowers of P. rex subsp. rex in an inverted position for pollen, which pollinated flowers sternotribically. We suggest that pollination mechanism is closely associated with floral morphology. Some important differences were found from a previous study on P. rex in floral morphology and the primary pollination mechanism.  相似文献   

15.
Diversity analyses in alfalfa have mainly evaluated genetic relationships of cultivated germplasm, with little known about variation in diploid germplasm in the M. sativafalcata complex. A collection of 374 individual genotypes derived from 120 unimproved diploid accessions from the National Plant Germplasm System, including M. sativa subsp. caerulea, falcata, and hemicycla, were evaluated with 89 polymorphic SSR loci in order to estimate genetic diversity, infer the genetic bases of current morphology-based taxonomy, and determine population structure. Diploid alfalfa is highly variable. A model-based clustering analysis of the genomic data identified two clearly discrete subpopulations, corresponding to the morphologically defined subspecies falcata and caerulea, with evidence of the hybrid nature of the subspecies hemicycla based on genome composition. Two distinct subpopulations exist within each subsp. caerulea and subsp. falcata. The distinction of caerulea was based on geographical distribution. The two falcata groups were separated based on ecogeography. The results show that taxonomic relationships based on morphology are reflected in the genetic marker data with some exceptions, and that clear distinctions among subspecies are evident at the diploid level. This research provides a baseline from which to systematically evaluate variability in tetraploid alfalfa and serves as a starting point for exploring diploid alfalfa for genetic and breeding experiments.  相似文献   

16.
亚沉茶渍亚洲亚种Lecanora subimmersa subsp.asiatica Zahlbr.曾被基于文献研究转隶至平茶渍属(Aspicilia)或处理为亚沉茶渍原亚种L.subimmersa(Fée)Vain.subsp.subimmersa的异名,但模式标本的研究缺乏仍使该变种的概念不清。利用形态学、解剖学和化学等方法对L.subimmersa subsp.asiatica Zahlbr.的模式标本进行了综合研究,发现L.subimmersa subsp.asiatica与滇茶渍[L.oreinoides(Körb.)Hertel&Rambold]的形态特征及次生代谢产物一致,故将L.subimmersa subsp.asiatica作为L.oreinoides的异名处理。依据研究标本,对滇茶渍进行了形态学描述,同时提供了相关形态学图片,澄清了亚沉茶渍亚洲亚种的概念。  相似文献   

17.
18.
Summary

In contrast to the traditional view that Scottish Bracken (Pteridium Scop., Hypolepidaceae sensu Page, 1976) is a single, uniform taxon, evidence is presented that two species, each represented by multiple subspecies, are present in Scotland. These belong to two different species complexes within Pteridium, the P. aquilinum complex and the P. latiusculum complex. The P. aquilinum complex is represented by P. aquilinum (L.) Kuhn, with at least three subspecies: subsp. aquilinum, subsp. atlanticum C.N. Page and subsp. fulvum C.N. Page. The P. latiusculum complex is represented by P. pinetorum C.N. Page & R.R. Mill with at least two subspecies, subsp. pinetorum and subsp. osmundaceum (Christ) C.N. Page. Only P. aquilinum subsp. aquilinum is an aggressive weed which is a widespread problem to man; the others are rare. The paper establishes the nomenclatural priorities, typification, taxonomy, morphology, known distribution and ecology of all bracken taxa so far known from Scotland. The typification of P. aquilinum is discussed. There is no conflict between the two lectotypifications of Try on (1941) and Sheffield et al. (1989); both relate to the common bracken of the mid- and southern-latitudes of Europe, for which the existing epithet aquilinum must therefore be retained. It is pointed out that some of the other European taxa of bracken might well also yet be found within the British Isles, as well as, perhaps, other (especially possible diploid) taxa as yet undescribed.  相似文献   

19.
20.
Abstract

Five populations belonging to three subspecies of Dianthus rupicola Biv. (D. rupicola subsp. rupicola, D. rupicola subsp. aeolicus, and D. rupicola subsp. lopadusanus) and growing in different geographical areas of Sicily were tested for seed germination at various temperatures. All populations showed high germination rates with an optimum temperature between 15°C and 25°C. Efficient seed germination might contribute significantly to the preservation of these subspecies which are currently exposed to several environmental threats.  相似文献   

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