Showing papers in "Taxon in 1992"
TL;DR: A procedure of combining trees obtained from data sets of different kinds, similar to Brooks's technique but for a different purpose, with the aim of combining these data sets, is detailed along with examples used in five unrepeated combinations from a total of 15 published datasets.
Abstract: Summary Baum, B. R.: Combining trees as a way of combining data sets for phylogenetic inference, and the desirability of combining gene trees. - Taxon 41: 3-10. 1992. - ISSN 0040-0262. A procedure of combining trees obtained from data sets of different kinds, similar to Brooks's technique but for a different purpose, with the aim of combining these data sets, is detailed along with examples used in five unrepeated combinations from a total of 15 published datasets. The procedure does not adjoin raw data sets, but instead combines the binary-coded factors of the trees, each tree from a different data set, together. This allows the combining of data that are only available as pair-wise distances with data obtained directly from characters of the organisms. It economizes the analysis of combined nucleotide sequence data which can be very large, and preserves information for each kind of data in the combination. The procedure allows for missing data as well, and can be regarded as a new consensus method - mathematical properties have yet to be investigated. The desirability of combining gene trees, obtained from molecular data, to enable the inference of species trees is discussed in light of using this procedure.
538 citations
TL;DR: This revised edition of Volume 1 of Flora of New South Wales incorporates a 64-page insert that lists all the updates to the information contained within the book, including taxonomic changes, new species descriptions, new data about species and changes to keys.
Abstract: Volume 1 of the landmark series Flora of New South Wales was first published in 1990, and describes the naturally occurring and naturalised ferns, cycads, conifers and some of the flowering plants of that state. - Since 1990, parts of Volume 1 have been made substantially out of date by wide-ranging revisions to taxonomy and the discovery or identification of new plant species - such as the 'living fossil' Wollemi pine, featured on the cover of this revised edition. - This revised edition of Volume 1 incorporates a 64-page insert that lists all the updates to the information contained within the book, including taxonomic changes, new species descriptions, new data about species and changes to keys. - These changes are cross-referenced from the original species or key entry in the volume to the relevant section of the insert, so where necessary readers can quickly check to see what changes have occurred. - Additionally, the reference list, glossary and index have all been revised.
424 citations
TL;DR: In this article, a method for preserving leaves for subsequent DNA analyses using a solution that is saturated (obviating precise field weighing of chemicals) with both NaCl and CTAB is presented.
Abstract: Details of a method for preserving leaves for subsequent DNA analyses using a solution that is saturated (obviating precise field weighing of chemicals) with both NaCl and CTAB are presented. Since the dry ingredients are easy to obtain and transport, the method can be utilized even at very remote sites. Results from fresh versus preserved leaves of Podophyllum, Polyalthia (3 spp.), and Taraxacum demonstrate that DNA suitable for restriction fragment analysis can be obtained from leaves that have been stored in the solution for up to one month at ambient temperatures and then frozen for over one year at -20?C (ultracold storage at -70?C is not necessary). Degradation of DNA with this new method appears to be less for some taxa than with previously proposed DNA extraction methods using dried leaves. Analyses of DNA from leaves collected at remote rain forest sites are demonstrated.
191 citations
TL;DR: This text approaches floral odour analysis using thin layer chromatography using thin layers chromatography and includes illustrations of flora morphology and anatomy.
Abstract: This text approaches floral odour analysis using thin layer chromatography. It includes illustrations of flora morphology and anatomy.
153 citations
116 citations
TL;DR: It is imperative that more authors state briefly their philosophy of infraspecific taxonomy so their classifications may be interpreted more clearly.
Abstract: Summary Hamilton, C. W. & Reichard, S. H.: Current practice in the use of subspecies, variety, and forma in the classification of wild plants. - Taxon 41: 485-498. 1992. - ISSN 0040-0262. Infraspecific classification of plants continues to be practiced commonly by taxonomists: c. 8 % of species monographed in 26 major journals and series during the period 1987-1990 were subdivided. Of those, c. 42 % were divided into subspecies only, 52 %o into varieties, 3 % into formae, and 3 % into taxa of more than one level. Subspecies and varieties are usually defined as requiring some integrity - geographic, ecologic, and/or phylogenetic beyond the morphological. Despite some attempts to differentiate between subspecies and variety, they are largely equivalent in practice. European taxonomists tend to favor subspecies, whereas their counterparts in the United States usually employ variety. Formae usually are defined as lacking any extramorphological integrity. Given the general inconsistency of practice found, it is imperative that more authors state briefly their philosophy of infraspecific taxonomy so their classifications may be interpreted more clearly. Taxonomists collectively should promote greater standardization of infraspecific classification.
109 citations
TL;DR: The Phytolaccaceae are not monophyletic, and the Caryophyllaceae and Mollugo are the only taxa examined that do not produce betalains but they are neither closely allied nor basal to other elements of the order.
Abstract: Phylogenetic relationships among selected families of the Caryophyllales were examined by analyses of nucleotide sequences of the large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (rbcL). Sequences from 12 Caryophyllalean families were examined using parsimony and bootstrap analysis. The parsimony analysis produced two minimal trees with 778 steps. Major clades supported by bootstrap analysis are (1) Amaranthus (Amaranthaceae), Atriplex and Spinacia (Chenopodiaceae); (2) Mirabilis (Nyctaginaceae), Rivina (Petiveriaceae), Phytolacca (Phytolaccaceae) and Trianthema (Aizoaceae); (3) Basella (Basellaceae), Alluaudia (Didiereaceae), Portulaca (Portulacaceae) and Schlumbergera (Cactaceae); and (4) Silene, Dianthus, Arenaria and Cerastium (Caryophyllaceae). The Caryophyllaceae and Mollugo are the only taxa examined that do not produce betalains but they are neither closely allied nor basal to other elements of the order. Stegnosperma is not allied with the Mirabilis-Rivina-Phytolacca-Trianthema clade. Thus, the Phytolaccaceae (s.l.) are not monophyletic.
96 citations
92 citations
TL;DR: Simulated data representing hybridity and divergence are presented to illustrate each method and to provide a prototype of how to document hybridity using the favored methods.
Abstract: The type of intermediacy that separates hybridity from divergence is not multivariate intermediacy; it is the coincidence of intermediate character states. For the purpose of showing hybridity, analyses should distinguish between the two types of intermediacy. (1) Hybrid indices fail to do so. (2) Principal components analysis does so only in an ambiguous way. (3) Pictorialized scatter diagrams properly present the evidence for an interpretation that is intuitive. (4) Counting characters as intermediate or not-intermediate is an explicit approach that allows for statistical evaluation given that certain assumptions are made. Simulated data representing hybridity and divergence are presented to illustrate each method and to provide a prototype of how to document hybridity using the favored methods.
85 citations
TL;DR: An Ecogeographical study of the genus Hordeum is presented, which aims at determining the distribution and habits of these animals in the Northern Hemisphere.
Journal Article•
TL;DR: Subcommittee 3C was the third of three subcommittees comprising the Special Committee on Lectotypification authorised by the Berlin Congress and was established to produce specific proposals aimed at avoiding disadvantageous changes in the usage of Linnaean generic names.
Abstract: Subcommittee 3C was the third of three subcommittees comprising the Special Committee on Lectotypification authorised by the Berlin Congress (see McNeill, 1987; Nicolson, 1988). The Subcommittee's mandate came from a proposal made by W. T. Stearn in connection with the discussion of Art. 8 Prop. A at Berlin (see Greuter & al., 1989: 46-54). Stearn suggested that as the consistent adoption of either the Britton & Brown (1913) choices of type for Linnaean generic names or those of Hitchcock (1929) and Green (1929) would fail to maintain current usage of some names, causing disruption, it would be better, where a conflict existed, to choose the type that would best maintain usage of the name in question. Subcommittee 3C was subsequently established to produce specific proposals aimed at avoiding disadvantageous changes in the usage of Linnaean generic names.
TL;DR: The data suggest the possibility that the two species should be treated as one and question the hypotheses of extensive hybridization, interpretation of series designations, and the phylogenetic interpretation of corolla shape at the superseries level in S. sect.
Abstract: Solanum berthaultii Hawkes and S. tarijense Hawkes have been recognized as distinct species by all authors since their description in 1944. Some authors have considered them as sister species, but more recently they have been treated as unrelated species belonging to separate superseries. Hypotheses of species boundaries and hybridization have been examined using principal components analysis, stepwise discriminant analysis, canonical discriminant analysis, and one-way analysis of variance. 25 morphological characters measured on four individuals from each of 84 living accessions from throughout their natural range were analysed. Extensive intra-accession, intraspecific, and interspecific variability have been found in many characters, including those previously given great taxonomic weight. 9 characters show no statistically significant differences between species or putative interspecific hybrids. The remaining 16 characters show statistically significant differences between species and putative hybrids, but show so much variability that repeatable identifications of some accessions would require the use of population samples. The data suggest the possibility that the two species should be treated as one. Other currentlyrecognized species within S. sect. Petota may need to be reevaluated for synonymy. The results also question the hypotheses of extensive hybridization, interpretation of series designations, and the phylogenetic interpretation of corolla shape at the superseries level in S. sect. Petota.
TL;DR: An INTKEY version of the data bank of the sedge genera of the world is described, and its use for interactive identification and data retrieval is illustrated.
Abstract: An automated data bank of the sedge genera of the world has been developed using the DELTA system. The 122 narrowly defined genera are described in detail in terms of morphology, anatomy, photosynthetic pathways, synonyms, ecology, distribution, and classification. This paper describes an INTKEY version of the data bank (available for MSDOS microcomputers), and illustrates its use for interactive identification and data retrieval.
TL;DR: Seed proteins studied by electrophoresis in 29 wild taxa of the genera Diplotaxis, Erucastrum and Brassica support the idea of a close affinity among all taxa, and are largely consistent with evolutionary patterns that had been inferred previously through the study of seed, seedling and fruit morphology.
Abstract: Seed proteins have been studied by electrophoresis in 29 wild taxa of the genera Diplotaxis, Erucastrum and Brassica (Brassicinae). Protein data were subjected to multivariate analysis, and the results were plotted on a two-dimensional scatter diagram. They support the idea of a close affinity among all taxa, and are largely consistent with evolutionary patterns that had been inferred previously through the study of seed, seedling and fruit morphology.
TL;DR: Results from current comparative morphological studies of both the phycoma and motile stages of fossil and modern Prasinophyceae indicate generic identity between the fossil Tasmanites E. Newton and the modern Pachysphaera Ostenfeld.
Abstract: Results from current comparative morphological studies of both the phycoma and motile stages of fossil and modern Prasinophyceae indicate generic identity between the fossil Tasmanites E. Newton and the modern Pachysphaera Ostenfeld. According to Article 58 of the International code of botanical nomenclature, names of fossil taxa yield priority to names of non-fossil taxa, but with algae excepted. Thus Tasmanites is the correct name for the taxon currently known as Pachysphaera.
TL;DR: The history of these fossils is summarized, an argument against conservation of the well known generic name Podogonium is made, and the neotypification of Gleditsia podocarpa A. Braun is addressed to address the relevant nomenclatural problems.
Abstract: The generic name Podogonium Heer has been used since 1857 for fossil legume fruits, seeds, and leaves from the Neogene of Europe. Podogonium is the most common legume genus in the Neogene of central and southern Europe, and has been reported from many fossil localities in Czechoslovakia (Buzek, 1971), Hungary (Kovats, 1856; Hably, 1992), Germany, and Switzerland (Hantke, 1954; Kirchheimer, 1957; Ruffle, 1963; Gregor & Hantke, 1980), as well as China (Guo & Zhou, 1992). The taxonomy and systematic relationships of these fossils have been treated in detail in Herendeen (1992). The literature pertaining to these fossils contains numerous nomenclatural errors. In this paper I briefly summarize the history of these fossils and then address the relevant nomenclatural problems. The paper concludes with an argument against conservation of the well known generic name Podogonium, and the neotypification of Gleditsia podocarpa A. Braun, which is the basionym for the new combination Podocarpium podocarpum (A. Braun) Herendeen. The fossil fruits which today are nearly universally known as Podogonium knorrii Heer, were known in the literature for 104 years before Heer (1857) published the generic name Podogonium. They were first illustrated by Knorr (1755), and were described under a variety of generic names during the period between 1825 and 1857: Cabomba Aublet (Koenig, 1825), Gleditsia L. (Buckland, 1836; Braun, 1845), Dalbergia L. (Unger, 1851), Copaifera L. (Kovats, 1856), Podocarpium Braun ex Stizenberger (Stizenberger, 1851), and Podogonium (Heer, 1857). After Heer's publication, the generic name Podogonium has consistently been used for these fossils, with the exception of Gregor & Hantke (1980) who assigned Podogonium to the extant genus Gleditsia. Note that although "Heer 1859" is usually cited as the validating publication and date for Podogonium, Flora Tertiaria Helvetiae, vol. 3, part 6, was issued in 1857. Previously published taxonomic treatments of Podogonium have varied considerably (e.g., Heer, 1857; Hantke, 1954; Kirchheimer, 1957; Ruffle, 1963; Buzek, 1971; Gregor & Hantke, 1980). I have followed those who have recognized P knorrii as the sole species of Podogonium. This decision was reached after evaluation of variation among the fossil leaflets and fruits. Heer (1857) distinguished five of his six
TL;DR: Rhoads et al. as discussed by the authors discussed the importance of spatial resolution and data accuracy for the develop- ment and use of herbarium data with geographic information systems (GIS).
Abstract: Summary Rhoads, A. F. & Thompson, L.: Integrating herbarium data into a geographic information system: requirements for spatial analysis. - Taxon 41: 43-49. 1992. - ISSN 0040-0262. This paper addresses the importance of spatial resolution and data accuracy for the develop- ment and use of herbarium data with geographic information systems (GIS). Using the Pennsylvania Flora Database as an example, we discuss the variable quality of the spatial information in herbarium databases and present suggestions for standardizing spatial infor- mation for future data collection. GIS applications are discussed and examples of these applications are provided.