National Repository of Grey Literature 49 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
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...
Fossil clown beetles (Coleoptera: Histeridae): early evolution of "beetle tanks"
Simon Pražák, Jan ; Prokop, Jakub (advisor) ; Růžička, Jan (referee)
Clown beetles (Histeridae) represent a diverse (>4500 described species) group of beetles with worldwide distribution (except Antarctica) and with exceptional diversity of occupied habitats. Specialisation on environments such as subcortical space, dung and carrion, tunnels of wood- boring insects, caves, sand deserts, beaches, rodent burrows or ant colonies, has led to remarkable adaptations of morphology and even radical changes of entire body shape. To understand evolutionary paths of this extraordinary group of beetles, fossils are of vital importance. In this study, I examined eight undescribed species of fossil Histeridae from mid-Cretaceous Burmese and Hkamti ambers. I provide morphological descriptions and discuss possible taxonomical position of these species based on morphological characters. I further tested the phylogenetic position of all Cretaceous Histeridae genera via a topology-constrained maximum parsimony analysis based on a set of 69 characters. Among the studied species, representatives of Abraeini and Paromalini are reported for the first time from the Cretaceous. I discuss evolutionary implications based on the new as well as other Histeridae fossils. Subcortical strategy was likely common in the Cretaceous histerids, now reported in three separate lineages. It is also...
Telomeric DNA sequences in beetle taxa vary with species richness
PRUŠÁKOVÁ, Daniela
(TTAGG)n sequence is an ancestral common telomere motif in insects, yet not ubiquitous, especially in beetle lineage. This study indicates that this sequence has been repeatedly lost and replaced by two known alternative telomeric motifs, the (TCAGG)n and (TTAGGG)n, or other unknown alternatives. (TTGGG)n found in one taxa has been proposed as a novel candidate sequence. However, telomeric motifs in many other beetle species remain still undiscovered. Taken together, our extensive mapping of telomeric motifs showed that the diversity is positively related to the species richness of taxa, regardless of the age of the taxa.
Diversity of the geotrupide genus Jekelius (Coleoptera: Geotrupidae)
Sommer, David ; Král, David (advisor) ; Bezděk, Aleš (referee)
The first part of this thesis focuses on the family Geotrupidae, with special focus on the representatives of the genus Jekelius. It summarizes the present and historical taxonomic concepts and phylogenetic relationships within this family. Moreover, the morphology of adults and larvae and the geographical distribution of individual taxa are described. In the section on the biology and ecology of the family, emphasis is placed especially on feeding strategies, breeding behaviour and parental care. The results of this thesis consist of three parts, 1) taxonomy, 2) molecular analyses, and 3) flow cytometry. The first part brings a taxonomic revision of the Jekelius brullei species complex defined here. This part focuses on redescribing each known species, as well as describing additional species not yet formally described. This thesis defines the distribution ranges of each species based on previously published literature and our own data. Molecular analyses performed in this thesis generated a phylogenetic tree including a significant part of the species of the Jekelius brullei species complex. The last part of the thesis presents results obtained by flow cytometry for representatives of the species complex Jekelius brullei and a number of other taxa of the family Geotrupidae. The discussion then...
Wing reduction in cockroaches (Blattaria)
Kotyk, Michael ; Kotyková Varadínová, Zuzana (advisor) ; Nedvěd, Oldřich (referee)
My bachelor thesis deals with the wing reduction in cockroaches and the causes of its appearance. Order Blattaria is the insect order with the third highest occurrence of apterous and brachypterous species. Yet still only a minimum of publications were performed to cover this topic. Therefore, I analyse in several chapters both the types of wing reduction as well as generally accepted theories explaining the reasons of its evolution in insects. Then I discuss their relevance in the case of order Blattaria. Namely, ecological theories, regarding interactions of insect and its habitat, and physiological theories, describing life history trade- offs and constrains related to wings. I present examples of species to every theory which are probably concerned. There are also examples of species which maintain the macropterous state, although no longer capable of flight and theories that explain the retention of macroptery. As a part of the thesis I have also included a phylogenetic tree of cockroaches with marked wing condition for each sex, which outlines evolutionary trends of individual groups within the order. Keywords: Blattaria, reduction, macroptery, brachyptery, aptery, habitat, life history trade-offs
Habitat shifts to aquatic environment and back to dry land in the evolution of Coleoptera
Sýkora, Vít ; Fikáček, Martin (advisor) ; Král, David (referee)
The order Coleoptera (beetles) includes both terrestrial and aquatic species. The whole order as well as for all suborders (Archostemata, Myxophaga, Adephaga and Polyphaga) in ancetrally terrestrial. Habitat shifts occured in all suborders except Archostemata. A single shift to aquatic environment is probable in Myxophaga and Adephaga, multiple independent shifts from aquatic to terrestrial environments took place in Polyphaga. Multiple secondary habitat transitions back to terrestrial life style occured in Adephaga, Myxophaga and Polyphaga. However, phylogenetic relationships and/or detailed habitat requirements of adults and larvae are still unknown for many groups. That is why a reliable reconstruction of the evolution of habitat transitions between aquatic and terrestrial environment is still impossible in many cases. Key words: Coleoptera, habitat shifts, aquatic environment, terrestrial environment, evolution, phylogeny, biodiversity, morphology, adaptation
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)
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...
Preferences of the main groups of pollinators for the functional floral traits
Malá, Karolína ; Janovský, Zdeněk (advisor) ; Hadrava, Jiří (referee)
This bachelor thesis summarizes the preferences of the main functional groups of pollinators towards floral traits of plants. Due to coevolution and mutual selection pressures, these two life forms have begun to adapt to each other and develop traits on which the future of their life depends. The plant seeks to attract its pollinators, thus ensuring efficient pollen transfer or reproduction for its species. Attractants are used to motivate visitors to its flowers. These attractants provide pollinators with either direct rewards (food, shelter, brood) or rewards in the form of sensory perceptions (colour, scent, morphology). Recently, it has become apparent that flower colour, morphology and the type of food reward offered by the flower have the greatest influence on pollinator choice. Based on preferences towards attractants, we can organize several functional groups whose representatives have the same or similar choice preferences. Key words Pollination syndromes, pollinator, selection pressures, plant traits, coevolution, preferences, fidelity, diptera, coleoptera, lepidoptera, hymenoptera, birds, colour, morphology, rewards
Forenzně významní zástupci řádu brouci (Coleoptera) vyskytující se na území České republiky
Wrzecionková, Nicole Elizabeth
The process of gradual settlement of the dead body by necrophagous insects plays an important role in forensic practice, especially when determining the time of death. This work deals with the decomposition of dead body of vertebrates, forensically important representatives from the order of Coleoptera in the Czech Republic. Experimental objects for our purposes were domestic pig and chicken. The research was realized from December 2017 to March 2019. During the study samples of larvae and adults were collected from the dead bodies and subsequently identified by anatomical-morphological and molecular-genetic methods. These methods were compared with each other. For research purposes was necessary to isolate the mitochondrial DNA, amplify the fragment of cytochrom c oxidase I (COI) gene by the PCR method and then sequencing it mitochondrial DNA. The BLAST and BOLD databases showed the same outputs and based on the results, the individuals were classified into individual families of the Coleoptera order.

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