National Repository of Grey Literature 49 records found  previous11 - 20nextend  jump to record: Search took 0.02 seconds. 
Výskyt a druhové zastoupení řádu brouci (Coleoptera) na Mohelenské hadcové stepi
Polášková, Alexandra
The diploma thesis is focused on the assessment of the difference in the occurrence of invertebrates in the monitored locality in the Czech Republic and on the evaluation of anthropogenic and environmental influences on the invertebrates. In the introduction, the characteristics of the order of the beetles, most important representatives of the studied area and anthropogenic impacts on the biodiversity of the beetles are described. The monitored territory was Mohelenská hadcová step, which is located in the Vysočina Region. The collection of beetles took place at five sites during the vegetative season in 2016 and 2017. The beetles were determined and evaluated on the basis of individual localities and ecological indices. The results were compared with our and foreign literature. At the end of the thesis are given the context and the possible effects on the occurrence of invertebrates.
Growth and sexual selection in selected representatives of scarabaeoid beetles (Coleoptera: Scarabaeoidea).
Vendl, Tomáš ; Šípek, Petr (advisor) ; Knapp, Michal (referee) ; Skuhrovec, Jiří (referee)
Flower chafers are well-known beetles with apparent sexual dimorphism. Yet, in contrast to other groups of scarab beetles, only little attention has been paid to various aspects of this phenomenon. It concerns also sexual dimorphism in size, which is very common in animals. Although ultimate causes of sexual size dimorphism have been extensively studied, the developmental mechanisms are still only poorly understood. We investigated proximate causes of sexual size dimorphism in several differentially dimorphic flower chafer species. We found that in highly dimorphic species the dimorphism started to develop already in the first instar and tended to accumulate through successive larval development. In contrast, the sexes in species with a relatively low dimorphism diverged in size during only one instar. Moreover, we found variability not only in when the dimorphism arises during development, but also how: sex-related differences in both the instar duration and average growth rate were the proximate causes of sexual size dimorphism. In addition, we showed that the sexes may differ also in growth trajectory - males had relatively longer period of rapid growth than females, even in cases where the absolute development times were similar in both sexes. Further, we focused on systematic survey of sexual...
Evolution, biogeography and systematics of moss-inhabiting flea beetles (Coleoptera: Chrysomelidae: Galerucinae)
Damaška, Albert ; Fikáček, Martin (advisor) ; Bezděk, Jan (referee)
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...
Phylogeny of the genus \kur{Caledonica} (Coleoptera: Cicindelinae)
KUDRNA, Arnošt
Phylogeny of the New Caledonian tiger beetle genus Caledonica is reconstructed using three phylogenetic trees.Brief description of New Caledonian habitats, geography and geological history are presented and results are discussed.
Taxonomy, phylogeny and phylogeografy of selected groups of aquatic beetles (Coleoptera: Hydrophilidae, Hydraenidae) of the Caribbean region
Deler-Hernández, Albert ; Fikáček, Martin (advisor) ; Ribera, Ignacio (referee) ; Archangelsky, Miguel (referee)
This thesis is focused in the representatives of beetle families Hydrophilidae and Hydraenidae of West Indies and adjacent regions. It consists of two parts, the phylogenetic part and the systematic part. The phylogenetic part focuses on the hydrophilid genera Phaenonotum and Crenitulus of Greater Antilles: beetles were sampled in all four main islands (Cuba, Hispaniola, Puerto Rico and Jamaica) and analyzed using the combination of molecular and morphological data. The genus Phaenonotum contains four single-island endemics, of which those from Cuba, Jamaica and Hispaniola are wingless and form a clade that diversified ca. 46 million years ago (Ma) and likely colonized the Caribbean via the GAARlandia land bridge. In contrast, the Puerto Rican endemic and the two remaining non-endemic species colonized the Greater Antilles by over- water dispersal during the Oligocene-Miocene. The analysis of the genus Crenitulus revealed that Greater Antillean species belong to two separate clades: the Crenitulus yunque clade endemic for Cuba and Hispaniola, and the Crenitulus suturalis clade containing specimens from Greater Antilles and from northern America. A detailed revision of the Crenitulus yunque clade using morphology and molecular-based species delimitation recognized 11 species locally endemic for...
Larval morphology of Goliathini (Coleoptera: Cetoniinae) and its contribution towards the understanding of the group's evolution.
Kouklík, Ondřej ; Šípek, Petr (advisor) ; Skuhrovec, Jiří (referee)
1 Abstract Currently there are almost 4000 described species of rose chafers (Scarabaeidae: Cetoniinae) but larvae of less than 200 species are described. In this work we studied larval morphology of 86 species belonging to 58 genera with focus on the tribe Goliathini. The larvae of 21 genera were studied for the first time. 77 morphological characters on head, mouth parts, legs and thoracal and abdominal segments were studied. This resulted into large matrix of morphological characters, which were further tested in separate phylogenetical analyses. A checklist of studied characters and their states and also large databasis of photographs of the characters are also amongst the results of the thesis. Five independent datasets were tested, three were based singly on morphology, one on molecular sequences and one on a combined dataset. The phylogenetic analysis was made by three methods, maximum parsimony, maximum likelihood and bayesian interference. Eleven different phylogenetic trees were obtained as a result, based on which we tried to reconstruct the relationships between the inner groups of Cetoniinae with focus on relationship of subtribes of tribe Goliathini. Monophyly of the tribe Goliathini as well as some other groups could not be confirmed, as well as the alleged basal position of the genus...
Feeding strategies in geotrupids (Coleoptera: Geotrupidae)
Sommer, David ; Král, David (advisor) ; Vondráček, Dominik (referee)
The work summarizes the biology (life histories) of the family Geotrupidae. Historical findings are confronted with current knowledge. The study is focused mainly on food strategies within the family Geotrupidae, their evolutionary origin, differences across taxa within the family and the existence of certain trends within different taxa and family as a whole. The nutritional strategies of adults and larvae are compared, as well as the conditions that can lead to a changesin feedings strategies. The general section parts are devoted to taxonomy and phylogeny of the subfamilies within the family Geotrupidae, adult morphology and larvae and their geographical distribution. In the section part dedicated to the biology of individual subfamily, in addition to the feeding strategies, the biotopes of individual taxa, the presence or absence of parental care, and the knowledge of nesting behavior of beetles are listed. The primary nutritional strategy of the family is coprophagy, but the change in food strategies has occurred in this family several times independently. No trend within the family was traced. Changing the feeding strategy from cognition to phytophagy occurred only once in evolution, and in adults of the subfamily Lethrinae. Both obligatory and facultative saprophagies have evolved in the...
The role of iridescent and UV reflectant coloration patterns in beetles (Coleoptera)
Vlach, Jan ; Šípek, Petr (advisor) ; Pecháček, Pavel (referee)
The bachelor thesis deals with the role of iridescent and UV reflectant coloration patterns in beetles (Coleoptera). The thesis is divided into two main parts. The first part describes in detail the different types of iridescent and UV reflectant coloration patterns, it deals with the physical origines of coloration and finally it presents examples of beetle species, which possess this types of coloration. The second part deals with the functional perspective of iridescent and UV reflectant coloration patterns. The coloration function is divided into visual and nonvisual part. The part dealing with visual function is focused on interspecific and intraspecific communication, while the part dealing with nonvisial function describes thermoregulation and mechanical function of coloration. Powered by TCPDF (www.tcpdf.org)
Phylogeny and evolution of habitat preferences of the subfamilies Rygmodinae and Sphaeridiinae (Coleoptera: Hydrophilidae)
Sýkora, Vít ; Fikáček, Martin (advisor) ; Zrzavý, Jan (referee)
Subfamilies Rygmodinae and Sphaeridiinae together form approximately one third of the extant diversity within the family Hydrophilidae (Coleoptera: Polyphaga). Members of both these subfamilies inhabit wide spectrum of aquatic and terrestrial environments including specialized habitats such as phytotelmata, carrion or termite nests. So far, habitat shifts within these subfamilies have been only tested with a limited amount of taxa at the family level. Using a broader sampling and Bayesian and maximum likelihood methods, genus-level molecular phylogenetic analysis and divergence dating were performed. The dataset included 96 taxa, representing all major clades (genus groups) in both subfamilies, sequenced for two mitochondrial and two nuclear genes. A single shift from the aquatic to terrestrial environment in the Middle Jurassic was suggested, thus revealing both subfamilies and all tribes as ancestrally inhabiting decaying plant material and leaf litter. Secondary returns to aquatic habitats were suggested for two lineages of the Rygmodinae and several lineages belonging to tribes Coelostomatini and Megasternini. A single shift to flowers was revealed in the subfamily Rygmodinae. Similarly, single independent shifts to the inquiline lifestyle in tribes Omicrini and Megasternini were revealed. In...

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