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Traditional Classification (traditional + classification)
Selected AbstractsComparative and functional morphology of the buccal cavity of Diplogastrina (Nematoda) and a first outline of the phylogeny of this taxon*JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 1 2000A. Fürst Von Lieven The Diplogastrina include about 290 species of free living nematodes. Traditional classifications of this taxon are not based upon hypotheses of phylogenetic relationships. The highly variable structures of the buccal cavity were examined in 21 species using light microscopy and SEM. The function of the stomatal structures was studied with the aid of video recordings of living worms. The morphological data were used to reconstruct a first outline of the phylogenetic relationships of the Dipolgastrina. A rhabditoid gymnostomatal tube which is longer than wide, a short stegostom and a small dorsal tooth as in Pseudodiplogasteroides belong to the stem species pattern of Diplogastrina. Diplogastrina with a ,Rhabditis'-like gymnostomatal tube feed on bacteria and small fungal spores. A short and broad gymnostom as well as a right subventral tooth which forms a functional unit with the dorsal tooth were acquired step by step in the ancestral line leading to Mononchoides and Tylopharynx. The cuticularized cheilostom was divided into six plates connected by pliable regions twice independently within the Diplogastrina. The teeth-bearing posterior part of the buccal capsule can move forewards by pushing apart the plates of the cheilostom so that the teeth can get in contact with food items that are too big to be sucked into the buccal cavity. Diplogastrina with a divided cheilostom can feed not only on bacteria, but also on larger fungal spores, ciliates or other nematodes. Tylopharynx is specialized to rip apart the cell wall of fungal hyphae with the movements of a dorsal and a subventral tooth in order to suck out the contents of the fungus. This shows that the transformation of the buccal cavity in Diplogastrina is linked with an expansion of ecological niches. [source] Searching for new morphological characters in the systematics of scleractinian reef corals: comparison of septal teeth and granules between Atlantic and Pacific MussidaeACTA ZOOLOGICA, Issue 2 2009Ann F. Budd Abstract Recent molecular analyses have challenged the traditional classification of scleractinian corals at all taxonomic levels suggesting that new morphological characters are needed. Here we tackle this problem for the family Mussidae, which is polyphyletic. Most of its members belong to two molecular clades composed of: (1) Atlantic Mussidae and Faviidae (except Montastraea) and (2) Pacific Mussidae (Cynarina, Lobophyllia, Scolymia, Symphyllia) and Pectiniidae. Other Pacific mussids (e.g. Acanthastrea) belong to additional clades. To discover new characters that would better serve as phylogenetic markers, we compare the skeletal morphology of mussid genera in different molecular-based clades. Three sets of characters are considered: (1) macromorphology (budding; colony form; size and shape of corallites; numbers of septal cycles), (2) micromorphology (shapes and distributions of septal teeth and granules), and (3) microstructure (arrangement of calcification centres and thickening deposits within costosepta). Although most traditional macromorphological characters exhibit homoplasy, several new micromorphological characters are effective at distinguishing clades, including the shapes and distribution of septal teeth and granules, the area between teeth, and the development of thickening deposits. Arrangements of calcification centres and fibres differ among clades, but the fine-scale structure of thickening deposits does not. [source] Clinical spectrum and histological analysis of 32 cases of specific cutaneous sarcoidosisJOURNAL OF CUTANEOUS PATHOLOGY, Issue 12 2006Cristina Mangas Background:, Sarcoidosis is a multisystem granulomatous disorder of unknown aetiology in which skin involvement is frequent. Objective:, To review histological characteristics of biopsies of specific cutaneous lesions of sarcoidosis and their relationship with clinical course. Patients and methods:, Biopsies from 32 patients with specific cutaneous sarcoidosis were reviewed. Histological findings and clinical characteristics of these patients were analysed. Results:, The initial clinical lesions of the patients were ten infiltrated nodule-plaques, eight papules, four maculopapular eruptions, five scar sarcoidosis, four subcutaneous nodules and one lupus pernio. Sarcoidal granulomas were located at dermis in 31 cases (74%) and at subcutaneous fat in 12 (28%) but only four were subcutaneous exclusively. Perivascular or periannexial distribution of granulomas was observed in eight cases (19%) and they had coalescence in 29 samples. The presence of foreign material was demonstrated in 11 cases (26%). Conclusions:, Clinical spectrum of specific lesions of cutaneous sarcoidosis showed a good correlation with granulomas localization in the biopsies. However, traditional classification of specific cutaneous sarcoidosis is often overlapping. On the other hand, foreign bodies and other atypical histological findings were more common than initially expected. [source] Avoiding misclassification bias with the traditional Charnley classification: Rationale for a fourth Charnley class BBJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 9 2006C. Röder Abstract Long-term follow up of patients with total hip arthroplasty (THA) revealed a marked deterioration of walking capacities in Charnley class B after postoperative year 4. We hypothesized that a specific group of patients, namely those with unilateral hip arthroplasty and an untreated but affected contralateral hip was responsible for this observation. Therefore, we conducted a study taking into consideration the two subclasses that make up Charnley class B: patients with unilateral THA and contralateral hip disease and patients with bilateral THA. A sample of 15,160 patients with 35,773 follow ups that were prospectively collected over 10 years was evaluated. The sample was categorized into four classes according to a new modified Charnley classification. Annual analyses of the proportion of patients with ambulation longer than 60 min were conducted. The traditionally labeled Charnley class B consists of two very different patient groups with respect to their walking capacities. Those with unilateral THA and contralateral hip disease have underaverage walking capacities and a deterioration of ambulation beginning 3 to 4 years after surgery. Those with bilateral THA have stable overaverage walking capacities similar to Charnley class A. An extension of the traditional Charnley classification is proposed, taking into account the two different patient groups in Charnley class B. The new fourth Charnley class consists of patients with bilateral THA and was labeled BB in order to express the presence of two artificial hip joints and to preserve the traditional classification A through C. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [source] Millipede phylogeny revisited in the light of the enigmatic order SiphoniulidaJOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 2 2003P. Sierwald Abstract The discovery of six specimens of the enigmatic order Siphoniulida, including for the first time males, prompted a modern re-analysis of current phylogenetic schemes for the class Diplopoda derived from traditional morphological and developmental characters. The data matrix was constructed and analysed using paup. The resulting phylogenetic hypotheses corroborated the longest standing, traditional classification, but also demonstrated clearly that more characters must be included to reach a better resolution. Recent alternative phylogenetic hypotheses and classifications are discussed in the light of the current analysis. The validity of a putative helminthomorph synapomorphy, the location of male gonopods on the 7th body ring, is discussed. Scanning electron microscopy corroborated morphological characters already described for the Siphoniulida: modified anterior legs, an apparently legless 3rd body ring, pyriform head, antennae with clavate setae, and absence of ozopores. The highly modified gonopods of the Siphoniulida are described for the first time; only the anterior legs of the 7th ring are modified into gonopods, the posterior legs of this ring are developed as normal walking legs. The gnathochilarium differs from the Colobognatha and consists of well-developed stipites with palps, elongated lingual plates with palps and a narrow central sclerite, most likely the mentum. Structures on the epiproct may possibly be spinnerets. Despite the discovery of adult males, the Siphoniulida are still considered Helminthomorpha incertae sedis . Zusammenfassung Die Entdeckung von 6 Exemplaren der ungewöhnlichen Ordnung Siphoniulida, einschließlich der ersten Männchen, erforderte eine Neu-Analyse der derzeitig diskutierten, morphologisch begründeten Klassifikationen der Klasse Diplopoda. Die erstellte Datenmatrize wurde in PAUP analysiert. Die sich ergebenden phylogenetischen Hypothesen bestätigen in wesentlichen die früheren, traditionellen Klassifikationsschemata; allerdings zeigt diese Analyse auch, dass die Merkmalsbasis erweitert werden muss, um eine höhere Auflösung zu erreichen. Neuere, abweichende phylogenetische Klassifikationen und Kladogramme werden unter Berücksichtigung der jetzigen Analyse verglichen. Die Gültigkeit einer der vorgeschlagenen Apomorphien für das Taxon Helminthomorpha, die Position der Gonopden am 7. Körperring, wird diskutiert. Rasterelektronenmikroskopische Untersuchungen bestätigten die morphologischen Merkmale, welche bereits für die Siphoniulida angegeben wurden: modifizierte Vorderbeine, scheinbar beinloser dritter Körperring, kleiner, zugespitzter Kopf, Antennen mit abgeflachten Borstenhaaren, fehlende Saftlöcher. Die männlichen Gonopoden werden hier zum ersten Male beschrieben: nur das vordere Beinpaar des 7. Ringes bildet die Gonopoden, das hintere Beinpaar desselben Ringes ist als normales Laufbeinpaar ausgebildet. Die Gonopoden sind stark modifizierte Strukturen. Das Gnathochilarium weicht deutlich von dem der Colobognathen ab, es besteht aus tastertragenden Stipites, langgestreckten Lingula Lamellae mit Tastern und einem zentralen, schmalen Sklerit, wahrscheinlich dem Mentum. Der Epiproct trägt vier Strukturen, die wahrscheinlich als Spinngriffel zu interpretieren sind. Trotz der Entdeckung von Männchen müssen die Siphoniulida weiterhin als Helminthomorpha incertae sedis angesehen werden. [source] Systematics of Chaetocerotaceae (Bacillariophyceae).PHYCOLOGICAL RESEARCH, Issue 2 2003SUMMARY In order to construct a model of evolutionary relationships within the diatom family Chaetocerotaceae, 37 species of Chaetoceros Ehrenberg, representing all subgenera and 21 of 22 subgeneric sections of the genus, plus three Bacteriastrum Shadbolt species, representing both of its subgeneric sections, were subjected to cladistic analysis. One species each of Eucampia Ehrenberg, Cerataulina Peragallo, Hemiau-lus Ehrenberg, Attheya West and Gonioceros H. & M. Peragallo were used as outgroups. A matrix of 65 binary and multistate morphological characters was constructed, with data being gathered from original observation of material in the light and electron microscopes, and from the published literature. The analysis yielded 36 most-parsimonious cladograms of 316 steps; incongruence between trees is largely restricted to some taxa representing undersampled sections of Chaetoceros subg. Hyalochaete. The robustness of this hypothesis was examined in several ways. To assess the effect of character weighting, the bootstrap was used to randomly weight characters. The parsimony criterion was relaxed via a decay index, and finally, the tree length was compared to that of trees randomly generated from the data matrix. The majority of investigated species of Chaetoceros subg. Phaeoceros, Chaetoceros subg. Hyalochaete and Bacteriastrum appear to belong to a continuous grade, rather than comprising individual clades. Chaetoceros is paraphyletic. Thus, the traditional classification does not accurately reflect the hypothesized phylogenetic relationships of this family. [source] Evolution of Funnel-Revolver Flowers and Ornithophily in Nasa (Loasaceae)PLANT BIOLOGY, Issue 1 2006M. Weigend Abstract: Floral morphology, distribution, and flower visitors for 60 taxa of Nasa are investigated and compared to molecular trees inferred both from a combined marker analysis (ITS1 and trnLUAA) and from a single marker (ITS1). Flowers conform to two different floral types: Firstly, "tilt-revolver flowers", with spreading to reflexed, white to yellow petals and small, brightly coloured floral scales contrasting with the petals and firmly enclosing the nectar (Saccatae and Carunculatae); secondly, "funnel-revolver flowers", with half-erect to erect, orange to red petals and floral scales not contrasting with the petals, or enclosed in the corolla, and nectar freely accessible by funnel-shaped floral scales (Alatae, Grandiflorae, and N. venezuelensis species group). Phylogenetic analysis shows that "tilt-revolver flowers" represent the plesiomorphic condition by outgroup comparison. The two groups with tilt-revolver flowers in Nasa are not monophyletic (Saccatae are paraphyletic, Carunculatae are polyphyletic). Most Saccatae fall into two monophyletic assemblages, the N. poissoniana species group and the N. triphylla species group. The remainder of Saccatae group either with Grandiflorae (N. insignis species group) or with Alatae (N. laxa species group). The clades retrieved in the molecular analysis contradict the traditional classification, but are congruent with vegetative morphology, details of the flower morphology, and biogeography. "Funnel-revolver flowers" represent the derived condition, but molecular data suggest a convergent development (at least twice independently), since the corresponding species do not constitute a monophyletic group. "Tilt-revolver flowers" are visited and pollinated by bees (especially Colletidae), whereas "funnel-revolver flowers" are mostly visited by hummingbirds. The transition from melittophily to ornithophily may have been the license for the colonization of, and the diversification in, both cloud forest and high Andean habitats. [source] Evolution of Filamentous Ascomycetes Inferred from LSU rDNA Sequence DataPLANT BIOLOGY, Issue 5 2000H. T. Lumbsch Abstract: The nuclear LSU rRNA gene was examined in order to evaluate the current phylogeny of ascomycetes, which is mainly based on nuclear SSU rRNA data. Partial LSU rRNA gene sequences of 19 ascomycetes were determined and aligned with the corresponding sequences of 13 other ascomycetes retrieved from Genbank, including all classes traditionally distinguished and most of the recently accepted classes. The classification based on SSU rDNA data and morphological characters is supported, while the traditional classification and classifications based on the ascus type are rejected. Ascomycetes with perithecia and cleistothecia form monophyletic groups, while the discomycetes are a paraphyletic assemblage. The Pezizales are basal to all other filamentous ascomycetes. The monophyly of Loculoascomycetes is uncertain. The results of the LSU rDNA analysis agree with those of the SSU rDNA and RPB2 gene analyses, suggesting that most classes circumscribed in the filamentous ascomycetes are monophyletic. The branching order and relationships among these classes, however, cannot be elucidated with any of these data sets. [source] Do larvae evolve the same way as adults in Tingidae (Insecta: Heteroptera)?CLADISTICS, Issue 2 2004Eric Guilbert A recent cladistic analysis showed that adult traits of Tingidae, which exhibit a great variety of shapes, evolved homoplastically from simple to complex (Guilbert, 2001). These complex traits, often exaggerated, were hypothesized to be adaptive. However, this study, as well as another by Lis (1999), both based on adult morphology, contradict the traditional classification of Tingidae. A new analysis is performed here, that includes larval characters, which, like those of adults, have a great variety of shapes. The results corroborate the traditional classification of the Tingidae. No clear divisions among Tinginae are drawn from the analysis, but an evolutionary pattern of shapes among Tingidae emerges from this study. There is a global tendency for larval traits to evolve convergently from simple to complex, as suggested for adults. The pattern seen in adult and larval traits is independent, but consistent. These traits can be used in the same anti-predation context, but with different roles. [source] Are Consumers Disadvantaged or Vulnerable?JOURNAL OF CONSUMER AFFAIRS, Issue 1 2010An Examination of Consumer Complaints to the Better Business Bureau Questions have emerged recently about the appropriateness of defining disadvantaged consumers based on their membership in certain demographic categories, such as income, age, education, and race. This study assessed whether these traditional classifications are useful for understanding consumer complaining behavior with the Better Business Bureau. Results of analysis of more than 24,000 consumer complaints filed with a local BBB office during a 13-year period do not provide consistent support for this disadvantaged consumer perspective. Instead, the emerging vulnerable consumer perspective may provide a more promising basis for future research. [source] | ||||||||||