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The influence of morphological and microstructural characteristics to land snail degradation in forest environment
Říhová, Dagmar ; Juřičková, Lucie (advisor) ; Bogusch, Petr (referee) ; Čejka, Tomáš (referee)
The decomposition of land snail shell is a complex process involving a number of factors and influences, including the characteristics of conchs themselves. In particular, it is the shell size with which the progress and the rate of degradation are tightly bound. Post-mortem changes begin with the loss of the original colour and, in the case of transparent species, by the opacification of the shell wall. Subsequently, the periostracum disruption and dissolution of calcium layers occur. However, this sequence may be reversed for some small species (e.g. Columella aspera, Nesovitrea hammonis). Animals mechanically destroy empty shells, humic acids from the substrate cause their artificial dyeing. Fungal mycelium or colonies of Streptomyces grow on the surface of the conchs. The plant roots are also involved in shell decomposition. While degradation of large shells starts with periostracum disruption and subsequent ostracal dissolution, periostracum of small shells persists even after dissolution of ostracal layers. The phenomenon is caused by high resistance of the periostraca of small species. In the case of large shells, periostracum has primarily a "building" function during shell formation, and sometimes it is flaking off already during the snail's life. For small species, it is an important part...
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Tribe Microdontomerini (Hymenoptera: Chalcidoidea: Torymidae) - phylogeny and evolution
Stiblík, Petr ; Janšta, Petr (advisor) ; Bogusch, Petr (referee)
Superfamily Chalcidoidea (chalcid wasps) represent the most species-rich group of the Hymenoptera and includes 22 families. Family Torymidae is one of those families and it's monophyly is currently intensively discussed. This particular thesis aims at the tribe Microdontomerini (Torimidae: Toryminae). Species of this tribe are usually minute inconspicuous wasps (body length ranges from 2 to 4 mm). Recent progress in phylogenetics of chalcid wasps allowes us to formulate robust hypothesis of Microdontomerini evolution, as a component of broader study of Chalcidoidea phylogeny and classification. My approach combines molecular and morphological evidence to formulate the most plausible evolutionary scenario. Dataset of 35 mostly morphological characters for 33 taxa including all existing Microdontomerini genera and 10 outgroups has been scored. Almost all characters has been studied and documented using Hitachi S-3700N-VP scanning electron microscope. In 117 taxa, 5 nuclear genes segments (18S, 28SD2, 28SD3-5, EF1alfa, Wingless) and 3 mitochondrial genes segments (COI-LCOHCO, COI-JerryPat, CytB) were sequenced, to get together the final molecular dataset of 387 Kbp. Molecular trees were built using maximum likelihood and Mr.Bayes algorithms. Evolution of morphological characters were mapped on the...
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Shape, surface and microstructural characteristics of landsnail shells and theirs function.
Holubová, Anna ; Juřičková, Lucie (advisor) ; Bogusch, Petr (referee)
Snails are popular group of invertebrates which intrigues people with their shell. Land snail shells take a variety of shapes and colors, their surface is covered by various surface structures. Shape of the shell is often afected by the environment in which snails live. Elongated shells are found on snails crawling along vertical surfaces, however snails with flattened shells crawl primarily on a horizontal surface. Keeled snails often hide in cracks in the rocks and under stones. Just as the shape is affected by the environment, so can the environment affect the surface structure and microstructure of the shell. We can find a snail with a shell that is covered with hairs in a humid environment and snails with thick periostracal layer in acidic one. The findings summarized in this thesis can be helpful to paleontological reconstructions of the environment, and in morphological identification of recent species by their shells.
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Biology of solitary bees of various families (Hymenoptera: Apoidea). A comarative study.
Žáková, Zdislava ; Straka, Jakub (advisor) ; Bogusch, Petr (referee)
The diploma thesis deals nesting behavior of the solitary bees Colletidae, Megachilidae, Mellitidae, Halictidae. The bees were monitored in their natural environment in the years 2009 - 2010. Course of their daily activities, number of nests per female, lenght of stay in the nest, length of life, active days and other species characteristics were monitored. By comparing the different nesting behavior patterns of the monitored species were found and pointed out the ones that are common and the unique ones. A nest uzurpation occurred (at all colonies) regardless the species. The (research) literature does not adress the issue of nest uzurpation in detail. Key words: nesting behavior, uzurpation, agression, bees, Hymenoptera
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Hymenopteran parasitoids (Hymenoptera: "Parasitica") and their impact on hosts species behaviour
Stiblík, Petr ; Janšta, Petr (advisor) ; Bogusch, Petr (referee)
Recently, many scientists have been focused on parasite or parasitoid host's manipulation. They don't describe only the changes in host behavior, but they even search for physiological background. Lots of papers dealing with hymenopteran parasitoids (Hymenoptera: Parasitica) host's manipulation have been published. The most studied are strongly adapted and host specific parasitoids, koinobionts. They developed very sophisticated mechanisms to manipulate their hosts for their own benefit. These parasitic wasps are not only very diverse group of the insect, but they even developed various ways to manipulate the hosts and their physiology. Sometimes the parasitoids use their hosts like a "food's vehicle", sometimes they manipulate just rates of some metabolites or suppress host's immune reaction. If the wasp's life-cycle is successful, the host does not develope to the adult's stage and is often consumed by the parasitoid larve.
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Nesting biology and ecology of selected sphecid wasps species (Hymenoptera: Sphecidae, Crabronidae)
Srba, Miroslav ; Vilímová, Jitka (advisor) ; Bogusch, Petr (referee)
Aim of presented work is to characterize and compare nesting biology and ecological requirements of five species of solitary wasps (Hymenoptera: Apoidea). Four species of family Sphecidae: Ammophila heydeni Dahlbom 1845, A. pubescens Curtis 1829, A. sabulosa (Linnaeus 1758), Sphex funerarius Gussakovskij 1934) and one representative of family Crabronidae (Bembix tarsata Latreile 1809) are treated here. Field observations were performed at spoil banks originated by coal mining by Most, Northwestern Bohemia. Obtained data bring exact parameters characterizing nesting habitats of studied species. Included are data on soil granulometry and penetrability, slope angle and vegetation cover. Significant difference between Ammophila species group and Bembix tarsata together with Shex funerarius was identified. Bembix tarsata and especially Sphex funerarius require softer soils and have broader valence in slope of nesting site sompared to Ammophila spp. Orientation of skew surface was almost south which has influence on microclimate of inhabited site microclimate. Biotic parameters such as cleptoparasite abundance were also tested. Three species of parasitic species Diptera: Sarcophagidae have been detected: Hilarella hilarella (Zettersedt, 1844), H. stictica (Meigen, 1824) a Metopia argyrocephala (Meigen, 1824)....
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