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Anatomical Characters (anatomical + character)
Selected AbstractsThe interspecific relationships of Astragalus species in Egypt assessed by the morpho-anatomical characters of the podFEDDES REPERTORIUM, Issue 5-6 2009M. M. Mourad The pod morphological and anatomical characters of 20 species, one subspecies and five varieties of Astragalus out of the 32 species growing in Egypt were investigated by LM and SEM, and numerically analysed to show the inter- as well as the infra-specific relationships. It was concluded that both A. trimestris and A. corrugatus show marked affinity to other species investigated in the present work. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Taxonomy of Late Jurassic diplodocid sauropods from Tendaguru (Tanzania)FOSSIL RECORD-MITTEILUNGEN AUS DEM MUSEUM FUER NATURKUNDE, Issue 1 2009Kristian Remes Abstract The Late Jurassic (Tithonian) Tendaguru Beds of Tanzania yielded one of the richest sauropod faunas known, including the diplodocines Tornieria africana (Fraas, 1908) and Australodocus bohetii Remes, 2007, the only known representatives of their group on the southern continents. Historically, the holotypes and referred material of both taxa plus dozens of additional specimens had been subsumed under the term "Barosaurus africanus " (Fraas, 1908). Here, the taxonomic status of the referred elements is reviewed by evaluating the phylogenetic information content of their anatomical characters, in order to provide a firm footing for further studies (e.g. of morphometrics, histology, and phylogeny of the Tendaguru sauropods). Some of the material shows diplodocine synapomorphies and may belong to either Tornieria or Australodocus, while other specimens are diagnostic only on higher taxonomic levels (Diplodocidae, Flagellicaudata, or Diplodocoidea indet.). The isolated limb elements in most cases lack phylogenetically diagnostic characters. Generally, the "Barosaurus africanus " sample shows a substantial grade of morphological variation, and it cannot be ruled out that there are more flagellicaudatans represented in the Tendaguru material than the diplodocines and dicraeosaurids already known. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] CONFUSING CONVERGENT MORPHOLOGIES: DIVERSITY AND DIFFICULTIES IN NEW ZEALAND ERYTHROPELTIDALES AND BANGIALESJOURNAL OF PHYCOLOGY, Issue 2000W.A. Nelson An examination of New Zealand species of Porphyra and Bangia has led to the discovery of unexpectedly high diversity. In excess of 30 species of Porphyra and 5 species of Bangia can be distinguished, based on 18S rDNA sequence data. It is possible to develop a workable taxonomic framework to distinguish species of Porphyra found within this geographic region using a range of characters (morphological, anatomical, biochemical, physiological, life history characteristics). However, the taxonomic distinctions do not necessarily reflect phylogenetic relationships revealed by sequence analyses: convergence in character states is obscuring relationships. In the course of our work we have discovered that four species, originally described on the basis of traditional morphological and anatomical characters as Porphyra or Bangia, are more closely related to members of the order Erythropeltidales than to the Bangiales. These results are challenging us to consider new ways of describing and defining these organisms. We are finding convergence in character states, not only within Porphyra sens. lat. But spanning both the Bangiales and Erythropeltidales, which confounds both taxonomic distinctions and also phylogenetic hypotheses based on morphology and anatomy. This confusion could be countered effectively by the inclusion of molecular sequence data based on vouchered or type material in descriptions of taxa in the orders Bangiales and Erythropeltidales. This would allow conclusive identification of collected material by appropriate molecular tests, which are quicker and more direct identification tools than, for example, using characters drawn from the growth of these organisms under controlled culture conditions. [source] Morphology and Anatomy of Shoot, Root, and Propagation Systems in Hoffmannseggia glaucaPLANT BIOLOGY, Issue 6 2007T. A. Kraus Abstract: Hoffmannseggia glauca is a perennial weed that has tubers and root-borne buds. Some authors only consider root tubers without mentioning root-borne buds, while others consider that more anatomic studies become necessary to determine the origin of these structures and to interpret their behaviour. The objectives are: to study the growth form of the plant in order to analyze the ontogeny of its propagation organs, and to study its shoot and root anatomical characters that affect water conductivity. Hoffmannseggia glauca was collected in Argentina. Development of its shoot and root systems was observed. Shoots and roots were processed to obtain histological slides. Macerations were prepared to study vessel members. Primary and lateral roots originate buds that develop shoots at the end of the first year. In winter, aerial parts die and only latent buds at soil surface level and subterranean organs remain. In the following spring, they develop innovation shoots. Roots show localized swellings (tuberous roots), due to a pronounced increase of ray thickness and parenchymatous proliferation in the root center. Root vessel members are wider than those of aerial and subterranean shoots. Early development of an extensive root system, presence of root borne buds, anatomic and physiological specialization of innovation shoots, capability of parenchymatous rays to originate buds and tuberous roots, and high water transport efficiency in subterranean organs lead Hoffmannseggia glauca to display higher colonization potential than other species. [source] Mesozoic Evaniidae (Insecta: Hymenoptera) in Spanish Amber: Reanalysis of the Phylogeny of the EvanioideaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 4 2010Enrique PEÑALVER Abstract: One new genus and five new species of the family Evaniidae are described from the Early Cretaceous (Albian) Spanish amber of Peñacerrada-I (Province of Burgos), San Just and Arroyo de la Pascueta (both in the Province of Teruel): Cretevania alonsoi sp. nov., C. montoyai sp. nov., C. alcalai sp. no v., C. rubusensis sp. nov., and Iberoevania roblesi gen. and sp. nov. Taxonomic changes include Cretevania pristina (Zhang and Zhang, 2000) comb. nov., C. exquisita (Zhang, Rasnitsyn, Wang and Zhang, 2007) comb. nov., C. vesca (Zhang, Rasnitsyn, Wang and Zhang, 2007) comb. nov., and C. cyrtocerca (Deans, 2004) comb. nov., as a result of the reinterpretation of the genera Procretevania and Eovernevania. The new well preserved specimens of the genus Cretevania, together with the characters shown by the type specimens of the synonymized genera, give new information about their anatomical characters of taxonomical importance, and the genus Cretevania Rasnitsyn, 1975 is re-diagnosed. The holotypes of the Russian species in amber have been revised. A cladistic analysis of fossil and extant groups of the superfamily Evanioidea is included. Cretevania had a wide palaeogeographic distribution, with the highest diversity known from Spain. The 13 known Cretevania species show a high interspecific variation mainly in wing characteristics, and a wide range of body and wing size. [source] Floral anatomy and systematics of Bretschneidera (Bretschneideraceae)BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2002LOUIS P. RONSE DE CRAENE FLS External morphology and anatomy of the flower and pollen of Bretschneidera sinensis Hemsl. are described to clarify the position of the family Bretschneideraceae relative to the Sapindales and the glucosinolate-producing families. Anatomical and micromorphological characters are investigated and sections are used to understand the structure of the flower. Observation of buds and sections reveal that the flower is obliquely monosymmetric, with the symmetry line running from one petal to a sepal. The upper petal shields the stamens and pistil and becomes positioned apically by the partial resupination of the pedicel. The octomerous androecium is characterized by variable empty positions which are related to the variable insertion of the three carpels. The loss of stamens is linked with a displacement of the remaining stamens. Floral anatomy demonstrates the presence of a nectary extending on the hypanthium from the base of the filaments to the base of the gynoecium. Details of floral anatomy are compared with members of Sapindaceae, Hippocastanaceae, Moringaceae, Akaniaceae, Tropaeolaceae and Capparaceae. Comparison with other characters supports a close relationship with Akaniaceae and Tropaeolaceae in an order Tropaeolales, in concordance with macromolecular results, either at the base of the glucosinolate clade, or in remote connection with the Sapindales. A number of floral anatomical characters with a strong phylogenetic signal are highlighted. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society, 2002, 139, 29,45. [source] Morphological and embryological characters of three middle Asian Allium L. species (Alliaceae)BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2001OZODBEK A. ASHURMETOV Morphological and embryological characters of the xerophilous species Allium crystallinum Vved., A. filidens Regel, and A. fritschii Khassanov et Yengalycheva (Allium subg. Allium) were compared. The morphology of flowers, the rate of development of male and female embryonic structures and correlations with bud dimensions were studied. The overall similarity of the embryonic processes and structures underlines the close taxonomic relationship of the species investigated as concluded from morphological and anatomical characters. However, several differences in embryological characters between A. filidens and A. fritschii confirm the separation of the latter species at species level. [source] Dicotyledonous wood anatomy and the APG system of angiosperm classificationBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1-2 2000PIETER BAAS FLS The recently proposed classification by the Angiosperm Phylogeny Group (APG) of angiosperms based on monophyletic groups as recognized mainly by molccular analysis is used here to discuss wood anatomical diversity patterns at the ordinal level. The APG orders are compared with the most recent ,classical' orders as listed in the second edition of 7 h e Plant Book for ,improved' or ,deteriorated' wood anatomical coherence. Although homoplasy in wood anatomical characters, largely due to ecoloqical adaptations, limits the value of wood anatomy at higher levels of classification, many families and orders tend to have characteristic combinations of microscopic wood features. Out of the 29 APG dicot orders, seven (Aquifoliales, Cucurbitales, Gentianales, Geraniales, Myrtales, Sapindales, Saxifragales) show an increase in wood anatomical homogeneity relative to their ,classical' predecessors; four APG dicot orders (Apiales, Ericales, Fabales, and Rosales) show a drcrrase, although within the orders several suprafamilial subclades are homogeneous. For the remaining 18 orders. wood anatomical diversity remains about the same as in previous classfications or the APG ordinal composition is almost identical to the ,classical' composition. The results support the value of both molecular markers and wood anatomical characters in phylogenetic classification. Because the ,classical' ordinal classifications have been partly inspired by wood anatomical information, one might have expected a ?greater wood anatomical coherence in them than in the largely molecularly delimited APG orders if wood anatomy did not provide significant phylogenetic sisgnals at higher taxonomic levels. The reverse appears to be the case. Among the wood anatomical characters included in the comparison, vestured intervessel pits, large and simple ray parenchyma pits, and sometimes also wide and tall rays appear to characterize orders. Some orders tend to be characterized by a combination of ,primitive' features in the Baileyan sense: scalariform perforations, fibres with distinctly bordered pits, apotracheal parenchyma, and heterocellular rays. This raises the question as to whethcr in thcsc cladcs this entire combination of characteristics should not he viewrd as synapomorphic rather than symplesiomorphic. [source] Multiple origins of symbioses between ascomycetes and bryophytes suggested by a five-gene phylogenyCLADISTICS, Issue 3 2010Soili Stenroos Numerous species of microscopic fungi inhabit mosses and hepatics. They are severely overlooked and their identity and nutritional strategies are mostly unknown. Most of these bryosymbiotic fungi belong to the Ascomycota. Their fruit-bodies are extremely small, often reduced and simply structured, which is why they cannot be reliably identified and classified by their morphological and anatomical characters. A phylogenetic hypothesis of bryosymbiotic ascomycetes is presented. New sequences of 78 samples, including 61 bryosymbionts, were produced, the total amount of terminals being 206. Of these, 202 are Ascomycetes. Sequences from the following five gene loci were used: rDNA SSU, rDNA LSU, RPB2, mitochondrial rDNA SSU, and rDNA 5.8S. The program TNT was used for tree search and support value estimation. We show that bryosymbiotic fungi occur in numerous lineages, one of which represents a newly discovered lineage among the Ascomycota and exhibits a tripartite association with cyanobacteria and sphagna. A new genus Trizodia is proposed for this basal clade. Our results demonstrate that even highly specialized life strategies can be adopted multiple times during evolution, and that in many cases bryosymbionts appear to have evolved from saprobic ancestors. ,© The Willi Hennig Society 2009. [source] The role of wood anatomy in phylogeny reconstruction of EricalesCLADISTICS, Issue 3 2007Frederic Lens The systematic significance of wood anatomical characters within Ericales is evaluated using separate and combined parsimony analyses including 23 wood characters and 3945 informative molecular characters. Analyses of wood features alone result in poorly resolved and conflicting topologies. However, when pedomorphic character states are coded as inapplicable, the combined bootstrap topology results in an increase of resolution and support at most deeper nodes compared with the molecular analyses. This suggests that phylogenetic information from the limited number of morphological characters is not completely swamped by an overwhelming amount of molecular data. Based on the morphology of vessels and fibers, and the distribution of axial parenchyma, two major wood types can be distinguished within Ericales: (i) a "primitive" type, nearly identical to the wood structure in the more basal outgroup Cornales, which is likely to have persisted in one major clade, and (ii) a "derived" type that must have evolved in at least two separate evolutionary lines. The occurrence of the first type is strongly correlated with shrubs to small trees growing in cold temperate or tropical montane regions, while the second type is common in tall trees of tropical lowlands. This favors the inclusion of ecologically adaptive features in phylogeny reconstruction. © The Willi Hennig Society 2006. [source] A Cladistic Analysis of the New World Species of Lotus L. (Fabaceae, Loteae)CLADISTICS, Issue 3 2000Ana M. Arambarri The genus Lotus L. is a monophyletic group diagnosed by the possession of a standard claw with thickened infolded margin, stamens diadelphous, and the style hardened from the base. It comprises approximately 200 species distributed throughout the world. A cladistic analysis of the New World species was performed using 39 morphological and anatomical characters (29 from seed morphology and anatomy, 1 from plant habit, 1 from leaf morphology, 6 from flower morphology, and 2 from fruit morphology). Dorycnium, Edentolotus, Krokeria, and Pedrosia, of the Old World, and 28 species of the New World were considered terminal taxa. Tetragonolobus Scop. was chosen to root the cladograms and Dorycnium Mill. to reroot them. With Tetragonolobus the analysis yielded 15 equally parsimonious trees, each with a length of 74 steps, a consistency index of 0.62, and a retention index of 0.89. The 15 initial trees and the strict consensus tree defined 12 monophyletic groups. All terminal taxa form a monophyletic group diagnosed by the presence of a radicular lobe discernible to conspicuous (character 10); rim aril thick (character 13); stipules absent (character 31); and style simple and nondilated (character 36). The New World species form a monophyletic group on the basis of the seed relationship of length to width in hilar view 1.5:1 to 2:1 (character 5); micropyle linear-deltoid to bifurcate (character 19); and keel erostrate (character 33). Identical monophyletic groups were obtained when Dorycnium was used as root. These results are discussed in the context of data on cytology and morphology. [source] | ||||||||||