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1.
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Species of Ficus subsection Urostigma show much overlapping variation in vegetative morphology, which often precludes correct identification of the species. The aim of this study was to describe the leaf anatomical characters and their variation and to check their suitability for identification. Included were 41 samples belonging to 25 species of subsection Urostigma, four samples belonging to two species of section Leucogyne and one specimen of Ficus glaberrima subsp. siamensis of subsection Conosycea. Transverse sections of lamina, midrib and petiole and cuticular macerations were used, and the observed anatomical characters are described for each species. On the basis of a limited number of studied samples, leaf anatomy shows little variation within each species and each species has a unique combination of character states, facilitating identification. Ficus arnottiana shows some leaf anatomical characters that are quite different from those of other members of subsection Urostigma, including a multiple epidermis and enlarged lithocysts on both sides of the leaf. Both characters are generally considered as typical for Ficus subsection Conosycea. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 175 , 259–281.  相似文献   

3.
Syconia (enclosed infructescences) infested with host-specific species of Schistonchus (Aphelenchoididae) were collected from six species of Ficus (Moraceae) native to Florida or Panama. They were sectioned and histologically examined to assess the effects of parasitism. Parasitism by Schistonchus spp. was associated with hypertrophied cells, tissue necrosis, and the presence of an exudate in all species. Occasional hypertrophy of the outer epidermal cells occurred on seed florets, wasp florets, and on the endothecial cells of male florets in F. aurea (subgenus Urostigma) from Florida. Aberrations of the inner mesocarp occurred under the hypertrophied cells on seed florets. In F. laevigata (subgenus Urostigma) from Florida, Schistonchus sp. infested immature male florets and was associated with hypertrophy of endothecial cells, epidermal cells of the anther filaments, and anthers. Schistonchus sp. also caused aberrations of the anther filament, anthers, and pollen. Ficus poponoei (subgenus Urostigma) and F. glabrata (subgenus Pharmacosycea), both from Panama, had hypertrophied outer epidermal cells on seed florets. Ficus poponoei also had Schistonchus sp. within the pedicel of an aborted floret, with hypertrophy of the cortical parenchyma. Ficus trigonata (subgenus Urostigma) from Panama had hypertrophy of the outer epidermis of seed florets. When the outer epidermis on these florets was missing, the inner mesocarp was hypertrophied. Ficus maxima (subgenus Pharmacosycea) from Panama had hypertrophy on the outer epidermis of seed and aborted florets. Schistonchus spp. were not found in wasp larvae or pupae in any of the Ficus spp. examined. Hypertrophy was never observed in the absence of Schistonchus spp.  相似文献   

4.
苏旭  蔡联炳 《植物研究》2009,29(1):113-117
观察了禾本科新麦草属、芒麦草属和三柄麦属主要代表种的叶片表皮形态学特征,总结了三属植物叶表皮结构的异同,探讨了叶表皮特征的分类学意义。同时,根据三属植物叶表皮性状的演化趋势,分析了各属的演化关系和系统位置。结果表明,新麦草属最原始,芒麦草属较进化,三柄麦属最高级;新麦草属可能直接派生了较进化的芒麦草属,并在芒麦草属的基础上进而产生了最高级的三柄麦属。三柄麦属、芒麦草属和新麦草属的这一系统关系同它们外部形态上三联小穗的演化趋势是相互印证的。  相似文献   

5.
The aim of this study is verification of the taxonomic usefulness of the pollen grain features studied, based on pollen morphology of 32 wild species from all 4 subgenera and all 10 sections of the genus Rosa, mainly for delimitation of subgenera, sections, and species. The measurements and observations were carried out with both light microscopy and scanning electron microscopy. Only correctly formed pollen grains (30 per specimen) were measured, and 960 pollen grains were examined in total. They were analyzed for 14 quantitative features of pollen grains and exine sculpturing and the following qualitative ones: outline, shape, and operculum structure. Our study revealed that the diagnostic features of pollen grains studied were: exine sculpture, length of polar axis, and pollen shape (P/E ratio). On the basis of the above characters, five species were isolated and the remaining ones were included in several groups isolated on the basis of exine sculpture types. The following three exine sculpture types occurred in the species studied: granular-verrucate (in R.?stellata), striate-psilate (in R.?multibracteata and R.?multiflora), and striate (the remaining species). R.?banksiae is characterized by small pollen grains, while R.?setigera has strongly elongated pollen with P/E ratio >1.5. Exine sculpture features considered to be diagnostic should be treated as auxiliary because they fail to differentiate individual species, although they can be helpful in distinguishing groups of species of similar exine sculpture. The arrangement of the species examined on a dendrogram only slightly corroborates division of the Rosa genus into subgenera and sections currently adopted in taxonomy (Rehder 1940). An interesting result was reported for the species studied from the Caninae (R.?agrestis, R.?canina, R.?dumalis, R.?jundzillii, and R.?rubiginosa) section which, despite hybrid nature, with the exception of R.?villosa, grouped in the same, most separated group of species.  相似文献   

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7.
《Palaeoworld》2019,28(3):381-402
The infrageneric taxonomy of the genus Cephalotaxus Siebold et Zuccarini ex Endlicher (Taxaceae) is controversial as morphological characters have been doubted to change coherently among species. Although the epidermal features are considered as important characters in the taxonomy of conifers, they have not been systematically studied in this genus. Neogene foliage shoots with well-preserved epidermal structure not only can provide systematic links to the extant species, but also have implications for the taxonomical definition of the extant species by their epidermal features. In this paper, the morphologies of leafy shoots combining epidermal structure of a Neogene Cephalotaxus, which was collected from the middle Miocene of Southwest China, and ten extant species (variants) were studied. Morphology as well as epidermal structures was compared among species (variants) in Cephalotaxus. Based on the comparisons, the taxonomical definition of extant species in genus Cephalotaxus are discussed. Our results indicate that leaf morphological characters in combination with the features of epidermal structure can distinguish species in genus Cephalotaxus. The fossil foliage shoots from the middle Miocene of Southwest China were assigned to a new species, C. maguanensis n. sp., which shows close affinities to the extant C. hainanensis. On the basis of leaf and epidermal information, we suggest there are seven extant species in Cephalotaxus. With global cooling and the uplift of the Qinghai-Tibet Plateau since the middle Miocene, the cooling climate induced the differentiation and southward expansions of C. maguanensis, and its extant offspring, C. hainanensis, is distributed to Hainan Island and the Indo-Chinese peninsula.  相似文献   

8.
Leaf epidermal (micromorphological and micromorphometric) features of the leaf blade were examined with light and scanning electron microscopy in 49 Central European natural populations of species belonging to subgenera Schedonorus and Drymanthele within the genus Festuca L. In addition, molecular biological (random amplified polymorphic DNA) studies were conducted on selected populations. The goal of the study was to reveal the degree of anatomical and genetic variability at the taxon and population level, as well as to determine the most important characters that allow differentiation of the taxa in these two subgenera. The anatomical variation was compared with the genetic distance between taxa. Investigated taxa exhibited great anatomic variability in terms of both qualitative (presence or absence, shape and appearance of various cell types) and quantitative characters (frequency and size of cells). Strong correlation was found between the genetic distance of populations and the frequency and size of silica cells in the costal zone of the epidermis, which indicates that silica cells are largely determined by the genetic background, regardless of varying environmental conditions. Our studies highlight that despite the high level of variability in anatomical features and genetic polymorphism, these fescue populations clearly segregate both in terms of epidermal structure and genetic constitution.  相似文献   

9.
Although species pairs and assemblages often occur across geographic regions, ecologists know very little about the outcome of their interactions on such large spatial scales. Here, we assess the geographic distribution and taxonomic diversity of a positive interaction involving ant-tended homopterans and fig trees in the genus Ficus. Previous experimental studies at a few locations in South Africa indicated that Ficus sur indirectly benefited from the presence of a homopteran (Hilda patruelis) because it attracted ants (primarily Pheidole megacephala) that reduced the effects of both pre-dispersal ovule gallers and parasitoids of pollinating wasps. Based on this work, we evaluated three conditions that must be met in order to support the hypothesis that this indirect interaction involves many fig species and occurs throughout much of southern Africa and Madagascar. Data on 429 trees distributed among five countries indicated that 20 of 38 Ficus species, and 46% of all trees sampled, had ants on their figs. Members of the Sycomorus subgenus were significantly more likely to attract ants than those in the Urostigma subgenus, and ant-colonization levels on these species were significantly greater than for Urostigma species. On average, each ant-occupied F.sur tree had 37% of its fig crop colonized by ants, whereas the value was 24% for other Ficus species. H. patruelis was the most common source for attracting ants, although figs were also attacked by a range of other ant-tended homopterans. P. megacephala was significantly more common on figs than other ant species, being present on 58% of sampled trees. Ant densities commonly exceeded 4.5 per fig, which a field experiment indicated was sufficient to provide protection from ovule gallers and parasitoids of pollinators. Forty-nine percent of all colonized F. sur trees sampled had ant densities equal to or greater than 4.5 per fig, whereas this value was 23% for other Ficus species. We conclude that there is considerable evidence to suggest that this indirect interaction occurs across four southern African countries and Madagascar, and involves many Ficus species. Received: 11 December 1997 / Accepted: 6 April 1998  相似文献   

10.
In combination with phytochemical results, the pilot chemotaxonomy study on genus Hedysarum by using HPLC methods revealed differences between section Fruticosa and the three other sections Multicaulia, Obscura and Subacaulia, but there was a closer genetic relationship with Multicaulia and Subacaulia. Isoflavonoids and pterocarpans were proved to be the common constituents of genus Hedysarum, whereas pterocarpans, benzofurans, and coumestans were the characteristic constituents of section Fruticosa, and chalcones were the chemical markers of section Multicaulia and section Subacaulia. The present finding is consistent with the classical morphological classification of genus Hedysarum, and provides supporting evidences for dividing Hedysarum into two subgenera, i.e. subgenus Hedysara and subgenus Ruticosa.  相似文献   

11.
The genus Deporaus from the Russian fauna is revised. Four species (D. pacatus, D. azarovae, D. septentrionalis, and D. hartmanni) of the subgenera Pseudapoderites and Japonodeporaus are found. Keys to the subgenera and to the species of the subgenus Pseudapoderites are given. The genus Deporaus, subgenera Pseudapoderites and Japonodeporaus, and four species are redescribed. The distribution of these species in Russia is discussed.  相似文献   

12.
13.

Background and Aims

The orchid genus Dichaea, with over 100 species found throughout the neotropics, is easily recognized by distichous leaves on long stems without pseudobulbs and flowers with infrastigmatic ligules. The genus has previously been divided into four sections based primarily on presence of ovary bristles and a foliar abscission layer. The aim of this work is to use DNA sequence data to estimate phylogenetic relationships within Dichaea and map the distribution of major morphological characters that have been used to delimit subgenera/sections.

Methods

Sequence data for the nuclear ribosomal internal transcribed spacers and plastid matK, trnL intron, trnL-F spacer and ycf1 for 67 ingroup and seven outgroup operational taxonomic units were used to estimate phylogenetic relationships within Dichaea. Taxa from each of the four sections were sampled, with the greatest representation from section Dichaea, the most diverse and taxonomically puzzling group.

Key Results

Molecular data and morphology support monophyly of Dichaea. Results indicate that section Dichaeopsis is polyphyletic and based on symplesiomorphies, including deciduous leaves and smooth ovaries that are widespread in Zygopetalinae. There are at least three well-supported clades within section Dichaeopsis. Section Pseudodichaea is monophyletic and defined by setose ovaries and leaves with an abscission layer. Sections Dichaea and Dichaeastrum are monophyletic and defined by pendent habit and persistent leaves. Section Dichaeastrum, distinguished from section Dichaea primarily by a glabrous ovary, is potentially polyphyletic.

Conclusions

The leaf abscission layer was lost once, occurring only in the derived sections Dichaea and Dichaeastrum. The setose fruit is a more homoplasious character with several losses and gains within the genus. We propose an informal division of the genus based upon five well-supported clades.Key words: Dichaea, matK, nrITS, Orchidaceae, trnL intron, trnL-F spacer, ycf1, Zygopetalinae  相似文献   

14.
Size and shape changes in the skull of the genus Gerbillus were investigated using geometric morphometrics. Six species from Tunisia were studied (G. gerbillus, G. campestris, G. nanus, G. tarabuli, G. simoni and G. latastei). Statistical analyses of shape variability allowed us to discriminate three morphological groups which are congruent with the three groups suggested by previous morphological and molecular studies. However, our results contrast with previous molecular investigations. In fact, according to results obtained by the use of principal component analysis, canonical variate analysis and UPGMA, we found a higher degree of divergence between the subgenus Dipodillus and the other two subgenera Gerbillus and Hendecapleura. This fact suggests that the morphometric differences observed among species within the genus Gerbillus are not mainly related to phylogeny. To reconciliate the molecular and morphological approaches, we propose a hypothesis of differential rates of phenotypic evolution in the genus Gerbillus. In this view, the species belonging to the subgenus Dipodillus evolved apomorphic features of the skull likely related to a higher degree of habitat specialization. By contrast, the more generalist Gerbillus and Hendecapleura subgenera show less differentiated plesiomorphic morphology.  相似文献   

15.
Hong Kong (22°N) is on the northern margins of the Asian tropics and has a native fig flora of 24 species. A total of 3.4 km2 of the urban area on Hong Kong Island was surveyed for spontaneous and planted fig plants of reproductive size. The 1124 individuals included 14 species in four subgenera: seven native species (F. fistulosa, F. hirta, F. hispida, F. microcarpa, F. pumila, F. subpisocarpa, and F. variegata), four of which were sometimes planted, one probably native (F. virens), one naturalizing species (F. religiosa), and five exotic species that occurred only in cultivation, two of which (F. altissima, F. rumphii) are pollinated and produce viable seeds. The native species in the two most common subgenera form distinct ecological guilds: those in subgenus Sycomorus bear large, many‐seeded, green or yellow figs and are bat‐dispersed pioneers on exposed soil; those in subgenus Urostigma bear small, few‐seeded, dark‐purple figs and are largely bird‐dispersed and epilithic. The density of potentially fruiting fig plants in the study area (2.3/ha) was within the range reported for tropical forests and between them they were visited by the entire urban frugivore fauna. This study shows the importance of the urban fig flora to urban wildlife and also highlights the risk of cultivated Ficus species becoming invasive, despite their obligate species‐specific pollinator mutualisms.  相似文献   

16.
Fruit-eating animals can influence the germination success of seeds through transportation and handling. We experimentally tested the contribution of ingestion by the common fruit-eating bat, Artibeus jamaicensis (Phyllostomidae, Chiroptera), to the percentage and rate of seed germination of figs (Ficus, Moraceae), which are considered keystone species for many frugivores. We collected fruits from three species of native free-standing figs (subgenus Pharmacosycea: F. insipida, F. maxima and F. yoponensis) and three species of native strangler figs (subgenus Urostigma: F. nymphiifolia, F. obtusifolia and F. popenoei) on Barro Colorado Island, Panama. The germination success of seeds removed from fruit pulp either manually or by ingestion was very high (>92%), while seeds that were not removed from fruit pulp were destroyed by fast-growing fungi within a few days. The dynamics of seed germination were not influenced by ingestion, but differed between the two subgenera of figs. In free-standing figs, germination started significantly earlier (5.3 ± 0.7 days) than in strangler figs (8.6 ± 1.4 days). Furthermore, strangler seeds were covered with a sticky coating and their seedlings developed cotyledons faster than fine roots, in contrast to free-standing figs that showed the opposite pattern. Our results demonstrate that the germination of fig seeds is positively influenced by passage through the gut of A. jamaicensis. Furthermore, free-standing and strangler figs revealed differences in germination parameters that might be adaptive with respect to the suitability of microsites such as tree fall gaps or host trees for establishment.  相似文献   

17.
Xiang H  Chen J 《Annals of botany》2004,94(3):377-384
Background and aims To understand the defensive characteristics of interspecies varieties and their responses to herbivory damage, four species of Ficus plants (Ficus altissima, F. auriculata, F. racemosa and F. hispida) were studied. They were similar in life form, but differed in successional stages. Of these, Ficus altissima is a late successional species, F. hispida is a typical pioneer and F. auriculata and F. racemosa are intermediate successional species. We addressed the following questions: (1) What is the difference in plant traits among the four species and are these traits associated with differences in herbivory damage levels? (2) What is the difference in the damage-induced changes among the four species?• Methods Herbivory damage was measured in the field on randomly planted seedlings of the four species of the same age. Defences to herbivory were also tested by feeding leaves of the four species to larvae of Asota caricae in the laboratory. A total of 14 characters such as water content, thickness, toughness, pubescence density on both sides, leaf expansion time, lifetime and the contents of total carbon (C), nitrogen (N), phosphorous (P), potassium (K), magnesium (Mg) and calcium (Ca) were measured. Leaf calcium oxalate crystal (COC) density, total Ca and N content, leaf toughness and height were measured to investigate induced responses to artificial herbivory among the four species.• Key results and conclusions Herbivory damage in the four studied species varied greatly. The pioneer species, F. hispida, suffered the most severe herbivory damage, while the late successional species, F. altissima, showed the least damage. A combination of several characteristics such as high in content of N, Ca and P and low in leaf toughness, lifetime and C : N ratio were associated with increased herbivore damage. The late successional species, F. altissima, might also incorporate induced defence strategies by means of an increase in leaf COC and toughness.Key words: Calcium oxalate crystals, defensive characteristics, Ficus; herbivory, induced defence  相似文献   

18.
Biogeography and conservation of the genus Ficus (Moraceae) in Mexico   总被引:1,自引:0,他引:1  
Aim The main objective of this study is to document the biogeographical patterns, endemism and degree of conservation of the species of Ficus (Moraceae) in Mexico. There are over 750 species of the genus Ficus distributed worldwide, and Mexico practically represents its northernmost limit in the American continent. Detailed studies at regional scales may help to understand the biogeography of large genera such as Ficus. Location Mexico. Methods The biogeographical patterns of Mexican Ficus were obtained from information of fig specimens available in two of the main herbaria of Mexico (2140 vouchers), collecting figs throughout this country, and revising the specialized literature. The presence of each species of Ficus was recorded for every one of Mexico's states and several tropical countries of America. Besides, the Mexican territory was divided into cells of 1° × 1° and the presence or absence of all species of the genus was recorded. Rarity of species was classified based on the width of geographic distribution, habitat specificity and population size. Results A total of 21 species of Ficus occur in Mexico, including six species (28.6%) that are endemic to this country. Five species are included in subgenus Pharmacosycea and 16 species are documented under subgenus Urostigma. Affinities of Ficus flora with other tropical countries in America generally decreased as geographical distances from Mexico increased. Mexican states and cells with highest values of Ficus species richness (both total and endemic species) were located. Ten species, including three endemics, presented a wide distribution. Five species, including two endemics, possess the three attributes of rarity (narrow geographical distribution, high habitat specificity and scarce local populations). Three species of Ficus, including the endemic and very rare Ficuslapathifolia (Liebm.) Miq., are not recorded in any protected area existing in Mexico. Main conclusions Most of the Mexican Ficus show a great morphological variation and occupy different habitats along their geographic distribution. The biogeographical patterns described here establish a fundamental scenario for ongoing studies on Ficus–pollinator interactions. However, many local populations are considered to be at risk, as there have been significant reductions in the number and size of local populations. Further studies are needed to understand the process of colonization, maintenance and persistence of fig–pollinator mutualism in species with different patterns of geographic distribution. Mexican Ficus require special policies for conservation due to their complex degree of rarity, particularly their geographic distribution in different types of vegetation, ranging from dry scrublands to tropical rain forests.  相似文献   

19.
The nucleotide sequences of the nuclear rDNA ITS regions were determined for 34 species of the genus Primula L. and one species of the genus Cortusa L., family Primulaceae Vent., and used to infer the phylogenetic relationships among these species. In this analysis species of the Russian flora and the flora of adjacent territories were studied for the first time. The results clarified the taxomic structure of the genus Primula and confirmed the entity of some of its sections; but not the subgenera sensu J.Richards. Our data do not support an independent status of the genus Cortusa, placing it as one of the terminal lineages of the section Cortusoides Balf. f. in the genus Primula.  相似文献   

20.
Evolutionary classification attempts to integrate information on shared ancestry, evolutionary process and phenetic information into the taxonomic concept. Here we exemplify this concept on the monophyletic, species-rich and cosmopolitan plant genus Ranunculus. Previous classifications have rendered almost all traditional sections as polyphyletic, and a modern revision based on phylogenetic principles was so far lacking. Maximum parsimony and Bayesian inference analysis of a combined nuclear (ITS of nrDNA) and plastid DNA dataset (matK/trnK, and psbJpetA) provided a phylogenetic framework for the genus with nine well-supported subclades. Neighbor Net analysis revealed a reticulate data structure within two subclades with frequent polyploidy and/or hybridization. Character evolution was studied by McClade reconstructions of morphological data mapped on to the molecular tree topology. Morphological characters show a mosaic-like distribution, but express several shared states congruent to molecular clades. A total evidence approach (TE) based on the combined morphological and molecular dataset suggests a subdivision of Ranunculus into a paraphyletic, temperate to arctic group of five subclades (subg. Auricomus), and a temperate to subtropical clade with four subclades (subg. Ranunculus). Infrageneric classification of two subgenera and 17 sections is based on both monophyly s.l. as evident from TE and a minimum of shared morphological characters. Six subclades have shared morphological or karyological features (sects. Auricomus, Flammula, Oreophili, Polyanthemos, Ranunculus, Thora, and Trisecti). One subclade was subdivided into three smaller clades according to morphological data (sects. Epirotes, Leucoranunculus, Ranuncella, Aconitifolii). In the case of reticulate evolution and uncertain ancestry we accept well-supported genetic clusters with shared morphological features, as revealed by Neighbor Net analysis (sections Batrachium, Hecatonia, Pseudadonis). Character evolution connected to ecological shifts characterizes the paraphyletic section Ranunculastrum, the holophyletic section Euromontani (sect. nov.), and the monotypic sect. Echinella. The information content of our classification is compared to alternative concepts.  相似文献   

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