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1.
MANNING, J. C. & BRITS, G. J., 1993. Seed coat development in Leucospermum cordifolium (Knight) Fourcade (Proteaceae) and a clarification of the seed covering structures in Proteaceae . The development of the seed coat and pericarp is studied in Leucospermum cordifolium from ovule to mature seed. The ovule and seed are characterized by a tegmic pachychalaza. The pericarp is adnate to the integuments from anthesis and remains unthickened to maturity. The outer integument forms the seed coat and the seed is endotestal: the outer epidermis becomes tanniniferous and the inner epidermis develops into a crystalliferous palisade. The inner integument degenerates at an early stage. Examination of the literature reveals that the crystal palisade layer of the outer integument has been erroneously assumed to constitute an endocarp. This finding indicates that a re-interpretation of all published information on the seed coat in indehiscent Proteaceae is necessary before any speculations on the phylogenetic significance of the seed coat can be entertained.  相似文献   

2.
Klasea , traditionally treated as a section in Serratula , is now widely accepted at the generic level. A classification of the genus is presented here, accommodating the 46 species in ten sections based on nuclear ribosomal DNA external and internal transcribed spacer sequence data and morphology. New combinations for five species and ten subspecies are published, and a new hybrid species is described. The genus ranges from the Iberian Peninsula and north Africa through southern and eastern Europe, west and central Asia to the Himalayas, and the Far East of Russia and China. The ancestral area is in west Asia, most probably eastern Anatolia and northern and western Iran. In this region, representatives of all sections are present. The largest section Klasea diversified most likely in the mountains of central Asia. A key to all Klasea species is provided.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 435–464.  相似文献   

3.
GORNALL, R. J., 1989. Anatomical evidence and the taxonomic position of Darmera (Saxifragaceae). Evidence from the anatomy of nodes, petioles, trichomes, leaf crystals, ovules and seed-surfaces agrees with other published data to show that segregation of Darmera from the Saxifragaceae is unwarranted. The combined evidence indicates that the closest relatives of the genus are Astilboides, Bergenia and Mukdenia. A putative hybrid origin for this group of genera is suggested.  相似文献   

4.
Leaf anatomy of 25 species in 15 genera of Caladeniinae (Diurideae, Orchidaceae), excluding Caladenia, was investigated to determine diagnostic characters to be used in forthcoming, broad-based cladistic analyses of the subtribe and to assess interspecific and intergeneric relationshipS. Of the characters examined, those that show the most variation among the study taxa are presence and types of trichomes, cuticular sculpturing, anticlinal walls of epidermal cells, heterogeneity of chlorenchyma, distribution and length: width ratios of stomata. Anatomical evidence supports the generic concept of Leptoceras Lindley but contradicts that of Drakonorchis Hopper & A.P. Brown. Paracaleana is not sufficiently distinct from Caleana to warrant generic status. Lyperanthus serratus and L.suaveolens are hyperstomatic, a rare condition in Orchidaceae. On the basis of these and other characters, Lyperanthus, as currently circumscribed, is polyphyletic. From leaf structure Caladeniinae as now conceived is polyphyletic and comprises seven groups: (1) Caladenia, Leptoceras, Elythranthera, Eriochilus, Glossodia, Aporostylis; (2) Adenochilus, Rimacola; (3) Arthrochilus, Chiloglottis, Spiculaea, Leporella; (4) Caleana (including Paracaleana); (5) Bumettia; (6) Lyperanthus suaveolens and L.serratus; (7) Lyperanthus nigricans.  相似文献   

5.
The genus Rhanteriopsis Rauschert, belonging to the f/iula–group of the Asteraceae–Inuleae, is monographed in a study based on herbarium material. Rhanteriopsis has a disjunct distribution with a westerly occurrence in Lebanon and Syria and an easterly distribution in Iran and Iraq along the Iranian border. Eour species are recognized: R. hombvcina (Boiss. & Hausskn.) Rauschert, R. lanuginosa (DC.) Rauschert, R. microcephala (Boiss.) Rauschert and R. puberula (Boiss. & Hausskn.) Rauschert. The morphology and phytogeography of the genus are discussed, a cladogram is proposed and a taxonomic treatment is provided.  相似文献   

6.
The anatomy and micromorphology of eleven species of Eugenia found in the 'restinga' of Marica, Rio de Janeiro, Brazil, were studied and compared. The characteristics found to be of most use in distinguishing the species are: presence and types of trichomes persistent in the adult material, form and arrangement of overlying cells (epidermal cells over secretory cavities), pattern of anticlinal walls of epidermal cells (primary sculpturing), occurrence of epicuticular striae and folds (secondary sculpturing) and presence of peristomatal folds. An analytical key based on these characteristics is presented for the Eugenia species studied.  相似文献   

7.
CRON, G. V., ROBBERTSE, P.J. & VINCENT, P. L. D., 1993. The anatomy of the cypselae of species of Cineraria L. (Asteraceae–Senecioneae) and its taxonomic significance. The anatomy of the cypselae of five species of Cineraria has been investigated to establish its potential usefulness for interspecific taxonomy. The usefulness is apparently limited. The most useful characters are the number of ribs, the extent of sclerenchymatization of the ribs and wings, and the surface sculpturing of the epicarp cells. The shape and symmetry of the cypselae are also useful to a limited degree. The presence of three resin canals in each cotyledon is constant. Their spatial differentiation is described.  相似文献   

8.
In the present study, seeds of 13 Oxytropis DC. species (including two latest synonyms) classified in subg. Oxytropis (sect. Dolichocarpon, sect. Chrysantha and sect. Eumorpha), subg. Euoxytropis (sect. Orobia) and subg. Phacoxytropis (sect. Protoxytropis, sect. Janthina and sect. Mesogaea) from Turkey were examined using light and scanning electron microscopy to evaluate the taxonomic relevance of macro- and micro-morphological seed characters. As a result of the study, species-specific characters have been determined. Seeds exhibit variation in size, shape, surface sculpturing pattern, hilum position and weight. Seeds ranged from 1.61 to 4.04 mm in length and from 1.02 to 2.56 mm in width. Five different seed shapes were recognised, as prolonged semielliptic, reniform, prolonged reniform, quadratic and cardiform, with a length to width ratio ranging from 1.02 ± 0.08 to 1.75 ± 0.27. Rugulate, rugulate–reticulate and lophate sculpturing patterns were observed in the studied species. According to the results, seed characters, such as the size (length, width and the length/width ratio), the shape, the surface sculpturing and the weight appear to have low taxonomic value in distinguishing subgenera, sections and species.  相似文献   

9.
同一株大核和焦核桂味荔枝的果实生长型均呈单S型,其果实大小差异主要由种子大小不同引起.果实发育期间,两者果皮中内源激素变化的规律大体上一致,大核果皮中GA3、IAA含量和(IAA ZRs GA3)/ABA比值均高于焦核果皮,但ZRs含量和ZRs/ABA比值则比其低,ABA含量的差异无规律可循.  相似文献   

10.
The trees and shrubs in Olearia sect. Divaricaster, sect. nov., are found in North, South, and Stewart Islands of New Zealand. They are distinguished by their small, opposite leaves borne on brachyblasts (short shoots), long shoots which abort apically, solitary or fascicled capitula, flowers with purple style arms, and a very distinctive insect fauna. The ten species and three subspecies, including the new O. fimbriata, O. gardneri and O. virgata subsp. centralis are revised and a key and distribution maps provided. The section includes four threatened species: O. hectorii, O. polita and the two new species. Species density is mapped in grid cells 1° latitude by 1° longitude. Areas west of the geological Median Tectonic Zone (Nelson, Westland and Fiordland) show relatively low diversity. The highest diversity, six species in one grid cell, is recorded in north-west Otago, around Mt Aspiring and the Humboldt Mountains. This region is also geologically significant as several allochthonous terranes are juxtaposed there. In the central South Island O. laxiflora, O. fimbriata and O. odorata have concentric distributions around what were Tertiary basins and inland seas. Members of the section favour fertile, lowland sites on alluvium and have suffered reduction in population size over the last century due to agricultural development. Several species, such as O. hectorii, the 'swamp gum', occur in sites which are periodically flooded. Olearia solandri is a coastal species, often growing as a mangrove associate, but occasionally found inland. The anomalous inland populations are discussed and their location attributed to geological uplift.  相似文献   

11.
Labellar food-hairs in Polystachya Hook. exhibit considerable morphological diversity. The commonest type of trichome is uniseriate, two to four-celled, with a clavate or subclavate terminal cell. This type occurs amongst representatives of most sections examined. Other trichomes are bristle-like with tapering or fusiform terminal cells, whereas representatives of section Polystachya have uniseriate, moniliform trichomes that fragment with the formation of rounded or elliptical component cells. Most contain protein and, while some contain starch, lipid is invariably absent. The presence of particular types of labellar trichomes does not coincide with variations in vegetative morphology. Thus, current taxonomic treatment of the genus indicates that trichome types, with perhaps the sole exception of moniliform, pseudopollen-forming hairs found in section Polystachya only, have limited taxonomic value. However, the remarkable similarity between pseudopollen-forming hairs of Polystachya and those of the Neotropical genus Maxillaria in terms of morphology, cellular dimensions and food content indicates that pseudopollen may have arisen several times and evolved in response to similar pollinator pressures.  相似文献   

12.
Systematic wood anatomy of the tribe Guettardeae (Rubiaceae). The wood anatomy of nearly all genera of the Guettardeae (Rubiaceae, Guettardoideae) has been examined, and in this respect the tribe is heterogeneous. Suggestions are made for a delimitation of the tribe. Guettarda, Bobea, Antirhea, Malanea and Chomelia Jacq. are sufficiently similar in their wood anatomical characters to warrant retention in the same tribe. Machaonia, Timonius and Dichilanthe are anomalous. Suggestions are given for taxonomic revisions of some genera based on their wood anatomy.  相似文献   

13.
Third instar larvae of members of the Ceratitis FAR complex, including Ceratitisfasciventris (Bezzi), Ceratitisanonae Graham, and Ceratitisrosa Karsch are described and compared with those of Ceratitiscapitata (Wiedemann). Diagnostic characters, such as presence vs. absence of a secondary tooth on the mandibles, previously used to separate Ceratitiscapitata from Ceratitisrosa, are shown to vary in each species. Significant variation in diagnostic morphological characters among populations of Ceratitisrosa from east and south Africa is documented; however, the differences are not simply congruent with the R1 and R2 designations based on other studies. Quantitative measures of numerous morphological characters are consistently smaller in the larvae of Ceratitisfasciventris and distinguish them from other species of the FAR complex. Larvae of Ceratitiscapitata can be distinguished from those of the FAR complex by characters such as absence of accessory plates of the oral ridges, the shape of the anterior spiracle, and the pattern of dorsal spinules. Previous studies indicated that absence of accessory lobes separate the genus Ceratitis from Bactrocera, but this is shown to be incorrect, as accessory lobes are in fact present in several species of Ceratitis.  相似文献   

14.
The West Indian fruit fly, Anastrepha obliqua, is one of seven species of quarantine importance of its genus and is one of the most economically important fruit fly pests in Colombia. The taxonomic status of this species is a key issue for further implementation of any pest management program. Several molecular studies have shown enough variability within Anastrepha obliqua to suggest its taxonomic status could be revised; however, there are no morphological studies supporting this hypothesis. The aim of this work was to describe the morphological variability of Colombian populations of Anastrepha obliqua, comparing this variability with that of other samples from the Neotropics. Measurements were performed on individuals from 11 populations collected from different geographic Colombian localities and were compared with populations from Mexico (2), Dominica Island (1), Peru (1) and Brazil (2). Linear morphometric analyses were performed using 23 female morphological traits, including seven variables of the aculeus, three of the thorax, and six of the wing; seven ratios among them were also considered. Discriminant function analyses showed significant morphological differentiation among the Colombian populations, separating them into two groups. Furthermore, in the comparisons between Colombian samples with those from other countries, three clusters were observed. The possibility of finding more than one species within the nominal Anastrepha obliqua population is discussed.  相似文献   

15.
The leaf anatomy of the subtribe Hyptidinae (Labiatae), which consists of four small genera and the largr genus Hyplis , is dercribed. The leaves may be dorsiventral or isobilateral. Variable characters of the lainina include: frequency and forms of trichomes, cuticular markings, presence of adaxial stoinata, thickness of leaf, thickness of adaxial epidermis, presence of a hypodermis, occurrence of sclcrified tissues (especially sclerified bundle sheath extensions, phloem and xylem fibres), mesophyll structure and venation pattern. Petiole vasculature varies from simple to complex, sometimes with medullary traces present. Most of the variable characters are related to xeromorphy and are tax-onomically useful within the framework of the present classification.  相似文献   

16.
An acid invertase (EC 3.2.1.26.) cDNA clone,CaAIV-18, was isolated from the red pericarp cDNA library of the hot pepper (Capsicum annuum L.) fruit. TheCaAIV-18 clone has 2223 nucleotides and one open reading frame encoding 641 amino acid residues. Analysis of deduced amino acid sequences reveals thatCaAIV-18 has a 24-amino acid transmembrane anchor region in its N-terminal, implying acid invertase in hot pepper may be localized in the membrane and not in the cytosol. This clone showed high homology to tomato acid invertase,Aiv1, in nucleotide and deduced amino acid sequences. In the Southern blot analysis, this clone proved to exist as single or low copy numbers on the genome of hot pepper. The clones had two well-conserved regions which appears in acid invertase of other plant species (eg. tomato,Arabidopsis, etc.) and yeasts. During fruit development,CaAIV-18 was expressed preferentially in the ripe red stage.  相似文献   

17.

Background and Aims

To date, the structure of the nectary spur of Aeridinae has not been studied in detail, and data relating to the nectaries of ornithophilous orchids remain scarce. The present paper compares the structural organization of the floral nectary in a range of Aeridinae species, including both entomophilous and ornithophilous taxa.

Methods

Nectary spurs of Ascocentrum ampullaceum (Roxb.) Schltr. var. aurantiacum Pradhan, A. curvifolium (Lindl.) Schltr., A. garayi Christenson, Papilionanthe vandarum (Rchb.f.) Garay, Schoenorchis gemmata (Lindl.) J.J. Sm., Sedirea japonica (Rchb.f.) Garay & H.R. Sweet and Stereochilus dalatensis (Guillaumin) Garay were examined by means of light microscopy, scanning electron microscopy and transmission electron microscopy.

Key Results and Conclusions

The diverse anatomy of the nectary is described for a range of Aeridinae species. All species of Ascocentrum investigated displayed features characteristic of ornithophilous taxa. They have weakly zygomorphic, scentless, red or orange flowers, display diurnal anthesis, possess cryptic anther caps and produce nectar that is secluded in a relatively massive nectary spur. Unicellular, secretory hairs line the lumen at the middle part of the spur. Generally, however, with the exception of Papilionanthe vandarum, the nectary spurs of all entomophilous species studied here (Schoenorchis gemmata, Sedirea japonica, Stereochilus dalatensis) lack secretory trichomes. Moreover, collenchymatous secretory tissue, present only in the nectary spur of Asiatic Ascocentrum species, closely resembles that found in nectaries of certain Neotropical species that are hummingbird-pollinated and assigned to subtribes Maxillariinae Benth., Laeliinae Benth. and Oncidiinae Benth. This similarity in anatomical organization of the nectary, regardless of geographical distribution and phylogeny, indicates convergence.  相似文献   

18.
19.
JURY, S. L., 1987. A new species of the genus Torilis Adanson (Apiaceae). The name Torilis nodosa (L.) Gaertner has been shown to have been used to include two very distinct variants. Torilis nodosa is therefore typified, and the other variant described as a new species.  相似文献   

20.
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