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1.
The ranges ofConsolea nashii andC. moniliformis were found to extend from the Bahamas and Hispaniola, respectively, into Cuba. Two new subspecies are now recognized on the basis of morphological and geographical discontinuities of populations:Consolea nashii subsp.gibarensis from the coastal thickets between Manatí and Maisí, northeastern Cuba, andC. moniliformis subsp.guantanamana from the cacti thorn-woodlands and thickets of Guantánamo and Santiago de Cuba Provinces, on the southern coast and adjacent dry plains of eastern Cuba. A key to the Cuban species ofConsolea is provided.  相似文献   

2.
Simaba guianensis subsp.huberi (Simaroubaceae), restricted to the savannas of the Venezuelan State of Amazonas, is described and illustrated. The new subspecies is distinguished from the other two subspecies ofS. guianensis by its smaller size, characteristics of the leaflets (size, texture, apex shape, and margin curvature), and fruit color.  相似文献   

3.
Peter F. Zika 《Brittonia》2003,55(2):150-156
Juncus effusus s. str. has two native representatives on the coast of western North America. A new combination is provided forJuncus effusus subsp.pacificus, ranging from California to British Columbia.Juncus effusus subsp.austrocalifornicus is newly described from southernmost California, Arizona, and Baja California, México. It differs from subsp.pacificus by its pale sheaths, with less thickened and less overlapping margins, and its disjunct distribution. A key is provided for the subspecies ofJ. effusus in North America.  相似文献   

4.
The phenology, reproductive cycle and cone crop of two sympatric subspecies ofJuniperus phoenicea (Cupressaceae) were studied during three consecutive years in southern Spain. The flowering pattern of each subspecies was constant during this period: inJ. phoenicea subsp.turbinata flowering was always in October–November, whileJ. phoenicea subsp.phoenicea flowered in February–March. There was no overlap between the flowering periods of the two taxa. The reproductive cycle of the two subspecies was similar, though there were some important differences because of their flowering times. Male cone development in both subspecies occurred in autumn, but the male cones ofJ. phoenicea subsp.phoenicea did not shed pollen until the end of February. InJ. phoenicea subsp.turbinata, the gap between pollination and fertilisation was seven months while inJ. phoenicea subsp.phoenicea it was only three months, fertilisation taking place at the same time in the two taxa. Post-fertilisation events were similar in the two subspecies, leading to a cycle of two years inJ. phoenicea subsp.turbinata and a shorter one of about 20 months inJ. phoenicea subsp.phoenicea. Alternating good and slight seed cone crops were found in both taxa during the three years studied, the good crops of one subspecies coinciding with the slight crops of the other one. Although the proximity of the two subspecies and method of pollination could make hybridisation between the taxa possible, the different flowering seasons prevent hybridisation isolating them reproductively.  相似文献   

5.
K. D. Hill  S.-L Yang 《Brittonia》1999,51(1):48-73
The genusCycas is revised for Thailand. Ten species are enumerated, five of them described as new (C. chamaoensis, C. clivicola, C. litoralis, C. nongnoochiae, C. tansachana), with one new subspecies (C. clivicola subsp.lutea). The species are placed within an infrageneric classification previously outlined. Distributions of the taxa are mapped, eight of the species are illustrated, and a key to species is provided. Previous records ofC. circinalis andC. rumphii from Thailand (here not regarded as indigenous in Thailand) are discussed.  相似文献   

6.
C-banding patterns ofH. brevisubulatum subsp.brevisubulatum (2x) and subsp.turkestanicum (4x) had conspicuous telomeric C-bands in at least one chromosome arm with a minor difference in average band size between subspecies. Other conspicuous bands were few in number as in other taxa of the species complex. The C-banded area of the chromosomes was estimated to be 7 to 8 and 6 per cent, respectively. C-banding- and SAT-chromosome polymorphisms were observed in both subspecies. The latter and previous observations indicate that the number of SAT-chromosomes is a less reliable diagnostic character. Nucleolar organizer region polymorphisms were demonstrated through silver nitrate staining of nucleoli. C-banding patterns corroborated that tetra- and hexaploid cytotypes of subsp.turkestanicum form an autopolyploid series. Reliable identification ofH. brevisubulatum taxa based on cytological criteria should include the simultaneous use of C-banding patterns, and number and morphology of marker chromosomes.  相似文献   

7.
Crepis incarnata subsp.dinarica (G. Beck)Hayek is nowadays considered as a subspecies ofC. praemorsa (L.)Tausch. Comparative analyses of Feulgen karyotypes demonstrate great similarities, but remarkable differences in the presence and the distribution of the constitutive heterochromatin in the two taxa are detected by using the Giemsa differential staining technique (C-banding). This favours their specific distinctness.  相似文献   

8.
Due to their ploidy levels, their morphological and anatomical characters and their distribution the central alpine Festuca stricta subsp. bauzanina (2n = 8x = 56) and Festuca ovina var. guinochetii (2n = 10x = 70), both belonging to the Festuca valesiaca group, are raised to the specific level. As a new subspecies Festuca bauzanina subsp. rhaetica is described here. The taxa of the polyploid Festuca valesiaca group are morphologically, anatomically and chorologically characterised and an identification key for these taxa in the central Alps is presented.  相似文献   

9.
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   

10.
Subspecific taxa of species complexes can display cryptic morphological variation, and individuals and populations can often be difficult to identify with certainty. However, accurate population identification is required for comprehensive conservation and breeding strategies and for studies of invasiveness and gene flow. Using five informative microsatellite markers and a Bayesian statistical approach, we developed an efficient polymerase chain reaction-based diagnostic tool for the rapid identification of individuals and populations of the Acacia saligna species complex of Western Australia. We genotyped 189 individuals from 14 reference populations previously characterised based on morphology and used these data to investigate population structure in the species complex. High total genetic diversity (H T = 0.729) and high population differentiation (θ = 0.355) indicated strong intraspecific structuring. With the provision of prior population information, the reference data set was optimally resolved into four clusters, each corresponding to one of the four main proposed subspecies, with very high membership values (Q > 97%). The reference data set was then used to assign individuals and test populations to one of the four subspecies. Assignment was unequivocal for all test individuals from two populations of subsp. lindleyi and for all but one individual of subsp. stolonifera. Individuals from populations of subsp. saligna and subsp. pruinescens showed a degree of genetic affinity for the two subspecies in their assignments, although the majority of individuals were correctly assigned to subspecies. The diagnostic tool will assist in characterising populations of A. saligna, especially naturalised and invasive populations of unknown origin.  相似文献   

11.
Parallel Evolution under Domestication and Phenotypic Differentiation of the Cultivated Subspecies of Cucurbita pepo (Cucurbitaceae). Cucurbita pepo (pumpkin, squash, gourd, Cucurbitaceae) is an ancient North American domesticate of considerable economic importance. Based on molecular genetic polymorphisms, two cultivated lineages of this species, each consisting of very many edible–fruited cultigens, have been recognized, C. pepo subsp. pepo and C. pepo subsp. texana. However, the phenotypic commonalities and differences between these two subspecies have not as yet been systematically collected and organized. Among the evolutionary developments common to the two subspecies are the increased size of the plant parts, less plant branching, and premature loss of chlorophyll in the exocarp of the fruits. In both subspecies, bush growth habit, conferred by allele Bu, is common to the cultigens grown for consumption of the immature fruits, as is the deviation from the 1:1 ratio of fruit length to fruit width. A major characteristic differentiating between the edible–fruited cultigens of the respective subspecies are the longitudinal protrusions, in subsp. pepo, versus depressions, in subsp. texana, of the fruit surface corresponding with the subsurface primary carpellary vein tracts. Subsp. pepo also has larger fruits and larger and longer seeds. In addition, some alleles affecting stem color, leaf mottling, multiple flower bud production, and fruit characteristics are frequently occurring to nearly fixed in one subspecies but are rare to less common in the other.  相似文献   

12.
One new species and one new variety ofBauhinia subg.Phanera sect.Caulotretus are described. Both taxa are tendrilled lianas with woody fruit and both are apparently endemic to Southern Bahian moist forest.Bauhinia carvalhoi has the smallest entire leaves known in the section.Bauhinia angulosa var.bahiana apparently replaces, in “Mata higrófila sul Bahiana”, the typical variety from southeastern Brazil. A key to the three taxa of this section known from Bahia is provided.  相似文献   

13.
Levels of variation revealed by starch gel-electrophoresis were compared with morphological and chemical variation within and among the species and subspecies ofVirgilia:V. oroboides subsp.oroboides, V. oroboides subsp.ferruginea andV. divaricata. The data sets exhibited concordance in that all point to a very close relationship between the taxa. Differences are mostly quantitative and an overlapping east-west gradient of character variation is indicated. Analysis of morphological and chemical characters showed thatV. oroboides subsp.ferruginea andV. divaricata are relatively distinct, whereas allozyme analysis indicated a high degree of genetic similarity among populations of these two taxa. The observed pattern of variation suggests relatively recent speciation with subsequent introgressive hybridisation resulting in a geographical and ecological gradient.  相似文献   

14.
Takahashi  Haruki 《Mycoscience》1999,40(1):73-80
Two lignicolous species ofMycena (Agaricales, Basidiomycetes) are described and illustrated from eastern, Japan:Mycena auricoma sp. nov., forming ephemeral coprinoid basidiomata and belonging to sectionRadiatae, was found on a dead fallen twig ofQuercus serrata. It appears to close to a Malaysian species,“Trogia” crinipelliformis. Mycena spinosissima in sectionSacchariferae, new to Japan, was collected from dead bark ofAphananthe aspera, a dead fallen inflorescence ofCryptomeria japonica, and a dead fallen twig ofQuercus serrata.  相似文献   

15.
A species-level review of the genus Clinopodium in Bolivia is presented. Characters used to distinguish taxa are discussed and evaluated with emphasis being given to nutlet characteristics for the first time. Nine species are described, seven from Bolivia, one of which, C. pilosum J. R. I. Wood is described as new. Bystropogon uniflorus Rusby ex Briq. is treated as subsp. uniflorum (Rusby ex Briq.) J. R. I. Wood of C. axillare (Rusby) Harley and its typification is discussed. Three subspecies of C. bolivianum are recognised, one of which subsp. diffusum J. R. I. Wood is described as new. Notes on salient characteristics of each taxon, on intermediate forms and on the distribution of each species are provided, as well as a key to species, maps and illustrations.  相似文献   

16.
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   

17.
18.
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   

19.
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   

20.
A new subspecies, Jurinea cataonica Boiss. & Hausskn. subsp. mardinensis B. Do?an & A. Duran (Asteraceae), is described and illustrated from Anatolia, Turkey. The subspecies grows on abandoned fields in the Bakirkiri place (C8 Mardin Province) in southeastern Anatolia. It is morphologically similar to J. cataonica subsp. cataonica. Diagnostic morphological characters between these closely similar taxa are discussed and arranged in a key. Ecology and conservation status of the subspecies is also presented. In addition, the geographical distributions of the new subspecies and other related species are given.  相似文献   

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