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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Bobrovití (Castoridae, Mammalia) ze spodnomiocénní (MN 3) lokality Ahníkov / Castorids (Castoridae, Mammalia) from the Early Miocene (MN 3) locality Ahníkov

Šmejkal, Roman January 2018 (has links)
Beavers are members of Castoridae - the family of large rodents characterized by a robust skull of sciuromorphic type, a sciurognathous mandible, dentition with a tendency to hypsodoncy and incisives by uniserial microstructure. The aim of the thesis is a detailed morphometric analysis of the fossil material of beavers coming from the early Miocene (MN 3a) locality Ahníkov I, II in the Czech Republic. In the numerous material comprising 388 fragmentary specimens, all belonging to the genus Steneofiber, two distinct species were distinguished, attributed here as - Steneofiber eseri (the larger form) and Steneofiber aff. dehmi (the smaller form). Their taxonomy, systematics and assumed position within existing phylogenetic models were discussed. Key words: Castoridae, Steneofiber, Czech republic, Ahníkov, MN 3, early Miocene
92

Výjimečné šváby (Blattidae) z cenomanského Myanmarského jantaru / Unusual cockroaches (Blattidae) from Cenomanian Myanmar amber

Šmídová, Lucia January 2018 (has links)
The diploma thesis presents an overview of the extinct representatives of Blattidae, the still living cockroach family. Six already described species, belonging to three genera, have been confirmed. All of them lived during Cenozoic. Eight new morphotypes from Myanmar amber were recognized. Cenomanian Burmite with its exceptional state of preservation, allows a detailed study of the morphology of the inclusions. Six morphototypes belong to the family Blattidae. One morphotype belongs to the derived family Olidae studied herein. One female morphotype belongs to the still living family Ectobiidae, based on the presence of an attached ootheca. The work specifies the previous molecular analysis (J2-K1) and determines the divergence of Blattidae during Early Cretaceous. Any evidence and interpolations before 127Ma is not substantiated. Phylogenetic analysis confirmed Blattidae being parafyletic in respect to the family Olidae. The work emphasizes the need for changes in systematics of the Mesoblattinidae, the stem of the Blattidae. Amber is confirmed as the product of coniferous trees of the Araucariaceae family. Key words: Blattidae, taxonomy, phylogeny, Cenomanian, Myanmar amber
93

Taxonomické principy, reprodukční systémy,populační genetika a~vztahy mezi vybranými skupinami rodu Taraxacum (Asteraceae) / Taxonomic principles, reproductive systems, population genetics and relationships within selected groups of genus Taraxacum (Asteraceae)

Zeisek, Vojtěch January 2018 (has links)
Chapter 3 Summary - shrnutí English and Czech summaries (abstracts) of the thesis. 3.1 English abstract Genus Taraxacum (Asteraceae), having ∼60 sections and 2,800 species, is known for its complicated evolutionary relationships and taxonomy due to processes like frequent hy- bridization, polyploidization, asexual reproduction, clonality and low structural morpho- logical variability. Various taxonomical concepts and approaches are reviewed, evaluated and discussed from point of view of their ability to deal with such a complicated genera as is Taraxacum. Various processes responsible for the complicated situation within Taraxacum are discussed and reviewed. Section Dioszegia, comprising T. serotinum and its allies, are an exception because only sexuals are reported for all the members of this group. On the basis of the analysis of mi- crosatellite (SSRs) variation, distribution and morphology, we addressed problems related to their mode of reproduction, among-population relationships, taxonomy and within- population variation. As a rule, outcrossing was the dominant mode of reproduction, with one notable exception: T. serotinum subsp. tomentosum (≡ T. pyrrhopappum) was autogamous and not heterozygous. A taxonomic revision of sect. Dioszegia recognizes T. serotinum subsp. serotinum (including an aberrant...
94

Amoniti spodního a středního turonu české křídové pánve / Lower and Middle Turonian ammonites of the Bohemian Cretaceous Basin

Kohout, Ondřej January 2018 (has links)
This thesis addresses the systematics and taxonomics of the ammonite assemblages of the Lower and Middle Turonian of the Bohemian Cretaceous Basin (BCB). It describes nineteen species of fifteen genera. Amongst others it concerns: Watinoceras coloradoense (Henderson), Spathites (Jeanrogericeras) reveliereanum (Courtiller), Paramammites sp. cf. P. polymorphus (Perervinquière), and Lecointricecras carinatum (Kennedy et al.) from the BCB, which have been described for the very first time. Another important taxon that is described is Prionocyclus albinus (Fritsch), which has not been encountered in the BCB since the year 1872 when it was established as a holotype by A. Fritsch. This specimen is now deposited in the National Museum in Prague. Most of these significant taxa belong to the collection of Dr. J. Soukup. He collected the specimens in various locations near Žďánice u Kouřimi mainly in the first half of the 20th century. The locations no longer exist. Stratigraphically important zonal ammonites, primarily W. coloradoense and Fagesia catinus (Mantell), are a direct evidence of the presence of two ammonite zones in the lower Lower Turonian in this part of the BCB (the zones Watinoceras coloradoense/devonense and Fagesia catinus). They also illustrate a larger stratigraphical extent of...
95

Čelistní aparáty hlavonožců české křídové pánve - taxonomie a stratigrafické implikace / Cephalopod jaws from the Bohemian Cretaceous Basin - taxonomy and stratigraphic implications

Kozlová, Zuzana January 2020 (has links)
This work is focused on systematic research of cephalopod jaws from the Late Cretaceous. Samples of 147 newly recorded nautiloid rhyncholites from the Bohemian Cretacoeus Basin and one new ammonite rhyncholite from Řepov village were systematically analyzed. The new collection of lower ammonite jaws (aptychi) consists of 32 specimens. Nautiloid rhyncholites from localities Turkaňk, Úpohlavy, and Dreisen were determined as Nautilorhynchus simplex. Conchorhynchs from locality Vinary u Vysokého Mýta belong to the species Conchorhynchus cretaceous, which is associated with the commonmost species Eutrephoceras sublaevigatum. Ammonite rhyncholite is left in the open nomenclature due to its uncertain systematic position and it is not assigned to any ammonite species. Records of aptychi from the locality of Úpohlavy and Pecínov represent mainly species of heteromorphic ammonites - baculitids (Baculites, Sciponoceras). The total diversity of species from both localities reaches 20 ammonite species. The two jaw morphotypes (2 species of aptychi) are reported from the Bohemian Cretaceous Basin for the first time herein. Of the high importance, it is a record of ammonite Prionocyclus germari from Úpohlavy with associated lower jaws in situ within the body chamber. Aptychus of this taxon has never been...
96

Il bordo urbano rurale : varianti morfotipologiche di paesaggi di-a contatto / Le bord urbain-rural : variants morpho-typologiques de paysages à contact / The urban-rural border : morpho typological variation of landscapes in contact

Perra, Aurora 27 April 2018 (has links)
Le sujet de la recherche est fondé sur l'étude du bord urbain-rural comme une structure territoriale qui accueille les dynamiques de contact, la transformation et l'hybridation des tissus. Le bord, à travers son épaisseur variable, est le milieu de l'interface, du changement, de la fragmentation et de la rupture. C’est intéressant d'étudier les caractères, la structure, les propriétés, les attributs, les adaptations que cet épaisseur assume, en se basant sur le caractère du lieu, la morphologie, l'utilisation des terres, sur la façon d'occupation de l'espace, sur les écologies relatives aux processus environnementaux et leurs implications dans le temps. C’est possible étudier spécifiquement ces phénomènes? Comprendre ses composantes, les raisons structurelles et de les interpréter dans une nouvelle pratique d’utilisation, d'emploi, de génération du bord? Le contact et les dynamiques qui en dérivent, nous permettent d'introduire le concept du changement d'état: la transmission des caractères d'un état à un autre (urbain-rural) comme nouvelle façon de lire les trasformations. La recherche est basée sur l'observation des études de cas en Sardaigne avec le but de construire une matrice de morpho typologies de paysages "en contact". L'objectif est pouvoir identifier et vérifier les processus de bord de qualité, et, par contre, les épisodes-processus qui affectent la qualité de ces espaces. Ces analyses seront réinterprétées sous forme de lignes directrices pour une révision plus consciente de l'espace du bord. / The theme of the search founds him on the urba-rural border study like a territorial structure that includes contact dynamics, the transformation and the hybridization among fabrics.The border, through his varying thickness, it is the place of the interface, of the mutation, of the fragmentation and the breakup. it is interesting to study the characters, the structures, the ownerships, the attributes, the adaptations that this thickness assumes, founding himself on the characters of the place, the morphologies, the uses of the ground, on the formalities of occupation of the space, on the ecologies related to the environmental trials and to their implications in the time. it is possible to study in the specific these phenomena? The contact among fabrics and the dynamics that derive of it, allows us to introduce the concept of passage of state, or rather the exachange of factors from a state to the other (urban-rural) as new way to read her transformations. The method of the search founds him on the observation and the analysis of a series of Sardinian cases study, with the objective to build a matrix of morfo typologies of "landscapes in contact". The objective is to be able to identify and to verify the processes of edge of quality and, contrarily, the episode-trials that injure the quality of the spaces. These analyses will constitute material of base for a reinterpretazione in the form of lines it drives for a more aware afterthought of the space of edge.
97

Evoluce, biogeografie a systematika mechových dřepčíků (Coleoptera: Chrysomelidae: Galerucinae) / Evolution, biogeography and systematics of moss-inhabiting flea beetles (Coleoptera: Chrysomelidae: Galerucinae)

Damaška, Albert January 2019 (has links)
Flea beetles (Alticini) are a highly diversified group of leaf beetles (Chrysomelidae) with about 8 000 known species from about 560 genera distributed worldwide except Antarctica. The major life strategy of flea beetles is external feeding on vascular plants, similarly to other leaf beetles. However, studies published during last years revealed existence of numerous different flea beetle genera feeding on mosses. Moss-inhabiting flea beetles are usually highly specialized and share similar morphological characteristics, including flightlessness, compact body shape and modified antennae. However, their phylogenetic position remained unknown. In this study, I performed a phylogenetic analysis of 14 known moss- and leaf litter inhabiting flea beetle genera, included into a large dataset of various genera of flea beetles. I sequenced 2 mitochondrial and 2 nuclear genes previously used for phylogenetic analyses of Alticini. I also added numerous Neotropical external feeding alticine genera, because taxon samples from previous studies (Ge et al. 2012; Nie et al. 2017) consisted mainly of Oriental genera. Although deep divergences and phylogenetic positions of several genera were not resolved, the analysis revealed a multiple origin of moss- and leaf litter inhabitance among flea beetles. The morphologically...
98

Polyarthra-Rotatorien - zyklomorphe Generationen oder ein Komplex zahlreicher Arten" Elektronenmikroskopische und DNA-analytische Untersuchungen

Leutbecher, Christine 17 March 2005 (has links)
Polyarthra-Rotatorien - zyklomorphe Generationen oder ein Komplex zahlreicher Arten? Elektronenmikroskopische und DNA-analytische Untersuchungen In der vorliegenden Arbeit wurde die Gattung Polyarthra (Rotatoria: Monogononta) taxonomisch untersucht. Dazu wurden licht- und rasterelektronenmikroskopische Untersuchungen sowie DNA-Analysen (RAPD-PCR) durchgeführt. Von den bisher 10 als valid geltenden Arten konnten Individuen von sieben Arten (P. euryptera, P. remata, P. major, P. dolichoptera, P. longiremis, P. vulgaris, P. luminosa) gesammelt und untersucht werden. Außerdem wurden Morphen bearbeitet, die Merkmale von verschiedenen Arten zeigten und keiner Art eindeutig zugeordnet werden konnten. Insgesamt wurden 31 verschiedene Polyarthra-Populationen aus 11 unterschiedlichen Gewässern untersucht. Ein Ziel der Arbeit bestand darin festzustellen, ob die unterschiedlichen Polyarthra-Morphen zyklomorphe einer bzw. weniger (bekannter) Arten sind oder ob sie mehrere distinkte Arten darstellen. Der Schwerpunkt der morphologischen Untersuchungen bezog sich auf den Trophus (Kauer), der bei Monogononten als artcharakteristisch gilt. Zeichnungen vom Habitus und/oder Trophus mehrerer verschiedener Morphen wurden als Originale oder aus der Literatur zusammengetragen, um einen umfangreichen Vergleich zu ermöglichen. Die DNA für die RAPD-PCR-Analysen wurde aus Einzelindividuen gewonnen, wobei die Optimierung der DNA-Isolierung im Vorfeld eigens dafür entwickelt wurde. Drei Random Primer pro Individuum konnten so angewendet werden. Sowohl morphologische als auch RAPD-Daten wurden Cluster-Analysen in Form von Parsimonie-Berechnungen unterzogen. Die RAPD-Daten wurden zusätzlich mit phänetischen Methoden berechnet. Die morphologischen und DNA-analytischen Daten lieferten danach folgende Ergebnisse: Das Auftreten von Zyklomorphose innerhalb der Polyarthren scheint eher selten zu sein. Die Validität der Arten P. euryptera, P. luminosa, P. major und P. remata konnte bestätigt werden. Nicht zweifelsfrei konnte P. vulgaris nachgewiesen werden. In Frage gestellt wird die Validität von P. dolichoptera und P. longiremis.
99

Diverzita a fylogeneze metopidních nálevníků patřících do skupiny IAC / The diversity and phylogeny of metopid ciliates of the IAC group

Pomahač, Ondřej January 2021 (has links)
The IAC group (Armophorea: Metopida: Metopidae) includes both free-living and endosymbiotic anaerobic ciliates. The thesis focuses on the diversity of free-living representatives, the so-called metopids. First, the position of the IAC group in the system is explained and the history of the taxonomy of the core species Metopus is presented. Then the taxonomic confusion surrounding this group is depicted. For diversity research more than 30 isolates from the IAC group were obtained from various anaerobic habitats and localities. The phylogenetic analysis of the IAC group is based on the 18S rRNA gene and shows a rich diversity of new lineages. In addition to the IAC group, another newly-found lineage of metopids is presented. Light microscopy, including staining techniques and scanning electron microscopy, was used to establish morphological characteristics. In the work, a detailed description of one selected lineage at the species level is performed. In the discussion, the results are interpreted, the limitations of the selected methods are pointed out and the chaotic taxonomic and phylogenetic situation of the IAC group species described. Suggestions for the improvement of future taxonomic practices in the description of metopids are offered.
100

Výjimečné šváby (Blattidae) z cenomanského Myanmarského jantaru / Unusual cockroaches (Blattidae) from Cenomanian Myanmar amber

Šmídová, Lucia January 2018 (has links)
The diploma thesis presents an overview of the extinct representatives of Blattidae, the still living cockroach family. Six already described species, belonging to three genera, have been confirmed. All of them lived during Cenozoic. Eight new morphotypes from Myanmar amber were recognized. Cenomanian Burmite with its exceptional state of preservation, allows a detailed study of the morphology of the inclusions. Six morphototypes belong to the family Blattidae. One morphotype belongs to the derived family Olidae studied herein. One female morphotype belongs to the still living family Ectobiidae, based on the presence of an attached ootheca. The work specifies the previous molecular analysis (J2-K1) and determines the divergence of Blattidae during Early Cretaceous. Any evidence and interpolations before 127Ma is not substantiated. Phylogenetic analysis confirmed Blattidae being parafyletic in respect to the family Olidae. The work emphasizes the need for changes in systematics of the Mesoblattinidae, the stem of the Blattidae. Amber is confirmed as the product of coniferous trees of the Araucariaceae family. Key words: Blattidae, taxonomy, phylogeny, Cenomanian, Myanmar amber

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