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Cytogenetics of bed bugs (Cimicidae) as a model representative of true bugs (Heteroptera)
Sadílek, David ; Vilímová, Jitka (advisor) ; Johnson Pokorná, Martina (referee)
Cytogenetics of bed bugs (Cimicidae) as a model true bugs (Insecta: Heteroptera) The thesis provides current opinions about a phylogeny of bed bugs, family Cimicidae, and their classification within the order Heteroptera. There are briefly summarized cytological data about the order Heteroptera, known karyotypes of the cimicid subfamilies and introduction to cytogenetics of species Cimex lectularius Linnaeus, 1758. Heteroptera species differ from other organisms by holokinetic chromosomes, a character, in which quite frequently take place chromosomal fragmentation and fusion. Several families posses smaller pair of m chromosomes, which behave during meiosis differently from the other chromosomes. Diploid chromosomal number is extremely variable, it ranges from four (family Belostomatidae) to 80 chromosomes (family Miridae). The behavior of chromosomes in the family Cimicidae is very specific. Sex-chromosomes univalents are connected by thread-like collochores and form so-called pseudobivalents during achiasmatic post-reductional meiosis. Rare polymorphism in a number of X chromosomes occurs in Cimex lectularius populations. The diploid karyotype always consists of 26 autosomal chromosomes and at least two but up to 15 X chromosomes and one Y chromosome. The number of X chromosomes can be variable...
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Comparative cytogenetics of bed bug Cimex lectularius (Heteroptera: Cimicidae)
Sadílek, David ; Vilímová, Jitka (advisor) ; Ráb, Petr (referee)
Comparative cytogenetics of the bed bug Cimex lectularius (Heteroptera: Cimicidae) The human bed bug Cimex lectularius has started enormous spreading to all developed countries of temperate climate zone during the last ten years. Bed bug was almost eradicated by a mass use of DDT in these areas until the 70's in the 20th century. This temporal haematophagous ectoparasite occupies particularly human dwellings and bat roosts. Cimex lectularius shows unusual combination of cytogenetic characteristics, general for all Heteroptera, however, not usual for other organisms. The chromosomes are holokinetic, with completely achiasmatic meiosis and inverted meiosis of the sex chromosomes. Especialy remarkable feature is intraspecific variation of the number of the X chromosomes. The variable number of chromosomes of 43 populations of Cimex lectularius from the Czech Republic and 27 populations from other European countries was studied in the present study. The 10 variants of karyotype were found out by using the "hotplate spreading" method and the standard Giemsa staining. There were male karyotypes with 2n = 29, 30, 31, 32, 33, 34, 35, 37, 42 and 47 chromosomes and two females with peculiar odd number of sex chromosomes X, 2n = 33 and 43, not complementary with any male. A stable number of 2n = 26 autosomes...
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Condition of dorsoabdominal scent glands in adults of the true bugs from the taxon Pentatomomorpha (Heteroptera)
Křížková, Petra ; Vilímová, Jitka (advisor) ; Kment, Petr (referee)
Existence of larval dorsoabdominal scent glands (DAGs) together with occurence of adult metathoracic scent glands is one of the important autapomorphic characters of taxon Heteroptera within taxon Insecta. DAGs can persist until adults in some species of this taxon. The persistence of DAGs were proved also in members of infraorder Pentatomomorpha. Targets of this thesis are: collect the knowledge about persistent adult DAGs in selected representative members of important families of taxon Pentatomomorpha; study and compare the condition of the DAGs in the oldest larval instars and adults; clarify the significance of existence the openings of conducting ductules of proper glandular units in reservoir intima of DAGs in study of the persistence of these glands. For study were used stereomicroscope, light and scanning electron microscope. Key words: Pentatomomorpha, Heteroptera, dorsoabdominal scent glands, openings of conducting ductules of glandular units, larvae of 5th instar, persistence in adults, persistence patterns, light microscope, scanning electron microscope
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Scent glands of true bugs (Heteroptera) and their pattern in micropterous bed bug Cimex lectularius (Cimicidae)
Wiesnerová, Markéta ; Vilímová, Jitka (advisor) ; Kment, Petr (referee)
Chemical communication is considered to be very common type of communication within the insects. Taxon true bugs, the suborder Heteroptera (Insecta: Hemiptera) is well known concerning this type of communication. It is based on a secretion of glands from which the most important are dorsoabdominal scent glands (DAGs) of nymphs and metathoracic scent glands (MTGs) of adults. The present study includes a summary of the knowledge about heteropteran scent glands, including the glands in micropterous bed bug, Cimex lectularius (Linnaeus, 1758) (Cimicidae). Also information about chemical composition and function of the secretion is included. Key words: Heteroptera, DAGs, MTGs, scent glands, bed bug Cimex lectularius, composition of secretion
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Condition of the larval scent glands in adults of the Heteroptera infraorders
Křížková, Petra ; Vilímová, Jitka (advisor) ; Kment, Petr (referee)
The Heteroptera scent glands system is formed by larval dorso-abdominal glands (= DAGs) and adult metathoracic glands ( = MTGs). The present study deals with a summary about occurrence of DAGs which are functional not only in larval but also in adult bugs, either proved or very likely. The part of general characteristics includes information about morphology, histology and functions of DAGs. The systematic review of published cases of DAGs' persitence in the adult stage represents the main part of the study. Recapitulations about possible positions of adult persistent DAGs and the characters used to prove gland functionality conclude the study. Based on the list of persistent adult DAGs, it is evident that they can be functional more often than was supposed. The DAGs functionality within heteropteran adults seems to be relatively widespread phenomenon, particularly in regards to a life in terestrial environment.
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Comparative morphology of structures associated with metathoracic scent glands in Heteroptera
Kment, Petr ; Vilímová, Jitka (advisor) ; Papáček, Miroslav (referee) ; Pluot-Sigwalt, Dominique (referee)
In my thesis, I studied the extemal structuresassociatedwith the metathoracicscent glands tn Heteroptera, partícularly in the superfamily Pentatomoidea' I focused on i) a review of terminology used for description oťmacrosculptureand microsculpture ofthese structures;ii) their morphology and structural diversity in partícularfamilies of Pentatomoidea;and iii) an attempt to homologize and polarize these structures and test their potential use for a phylogenetic hypothesis in Pentatomoidea. The followíng main terms are selected for description of the macrosculpture(thoracic Scent efferentsystem (intemal and extemal),valvular apparatus,intemal onfice, vestibule,vestíbular scar, ostiole, periostiolar depression,peritreme,auricle, spout, groove, rug4 disc, pentremal lobes, evaporatorium,and gyrification) and microsculpture(mycoid microsculpture,mushroom body, cap, stem, bridge, alveole, trabeculae,and peritremal microsculpture).These terms are defined,andan extensivelist ofsynonyms for eachofthem is compiled. The structures of the extemal scent efferent system are described for all families of the Pentatomoídea'The following conditions of the extemal scent efferent system are considered plesiomorphic: vestibular scar developed; ostiole situated between mesoacetabulum and metacetabulum,large,round or oval,...
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Phylogeny of parasitic wasps of Torymidae (Hymenoptera: Chalcidoidea) and evolution of their life-strategies
Janšta, Petr ; Vilímová, Jitka (advisor) ; Bryja, Josef (referee) ; Melika, George (referee)
The thesis is focused on phylogeny of the family Torymidae (Hymenoptera: Chalcidoidea) and evolution of their life-strategies. The study consists of general introduction to the phylogeny and classification of the family Torymidae chapter, four published papers in international journals and one manuscript prepared for submission. Firstly, our aim was to figure out the phylogenetic position of Torymidae as well as the position of other chalcidoid families inside superfamily Chalcidoidea (paper I and II). The supermatrix of sequencies of two ribosomal genes (18S rDNA and 28S rDNA) were developed for 649 species of chalcidoid taxa. However, family Torymidae was considered as polyphyletic group with the subfamily Megastigminae unrelated to the subfamily Toryminae (paper I). Monophyly of Torymidae was corroborated in another study (paper II) focused on molecular and morphological characters. We used a web-based, systematics workbench mx database for scoring 233 characters of 300 members of all chalcidoid families. Contrary to our previous only DNA-based study, we revealed also potential sister relationships of Torymidae with Ormyridae+Colotrechninae or Cerocephalinae+Diparinae respectively. Other paper (paper V) was focused on detailed study of Torymidae phylogeny. A total of 5 genes (18S rDNA, 28S rDNA,...
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Evolution of cleptoparasitic behavior in bees (Hymenoptera: Apoidea)
Straka, Jakub ; Vilímová, Jitka (advisor) ; Zrzavý, Jan (referee) ; Yanega, Douglas Andrew (referee)
Cleptoparasitic behaviour is widespread life strategyin bees (Hymenoptera:Apoidea). More than |5oÁof all bee species are obligate cuckoo bees.It is not the only form of cleptoparasitic behaviour in this insect group, but is by far the most common. Cleptoparasitism can be an obligate as well as an occasional life tactic occuring among pollen-collecting bees.The most simple, but rare cleptoparasiticstrategyin bees is theft of supplies. Bees can steal pollen supplies outside the nest (directly from legs of other bees)or inside of conspecific nest.Robbing (inside nest theft) is an obligatory strategyin some eusocíalstinglessbees(Apinae: Meliponini). Usurpation is anotheroccasional life strategyof normally pollen-collecting bees.[t seemsto be quite common, although it is largely overlooked by observers.Individual marking of nesting females as well as inside nest behaviour can reveal several differentusurpation strategies.The most common is nest usurpationsometimes leading to discarding of cells of the preceedingfemale (host).In some casesonly the nestentranceis usurpedand the new owner is not in contact with the host cells; this can be called nestingarea usurpation. The best-studiedkind of cleptoparasitismis brood parasitism.It rarely occures on the intraspecific level, but it is frequent in its...
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Cytogenetic characteristics of the genus Cimex (Heteroptera: Cimicidae)
Sadílek, David ; Vilímová, Jitka (advisor) ; M. Grozeva, Snejana (referee) ; Král, Jiří (referee)
The present thesis deals with the phenomenon of additional sex chromosomes in Cimex lectularius (Hemiptera: Heteroptera: Cimicidae) using genome size analysis combined with the classical cytogenetic approach. Also, five other cimicid species and 12 species from the family Nabidae were analysed identically for comparative purposes. The thesis also pursues a description of methodical approaches of cytogenetics and flow cytometry in the study of C. lectularius. Recently analysed European specimens of C. lectularius from human host exhibited 12 distinct cytotypes, with a variable number of chromosomes X from two to 20 (2n♂ = 26+X1X2Y to 26+X1-20+Y). The fragmentation hypothesis of C. lectularius additional chromosomes X origin was established in the second half of the 20th century. However, the present genome size measurements suggest that various chromosomal rearrangements as duplication or deletion besides the fragmentation could occur. Males with basic cytotype 2n = 26+X1X2Y had average genome size of 2C = 1.94 pg, in contrast male with 2n = 26+X1-7+Y yielded 2C = 2.26 pg and also specimens with genome size decrease 2C = 1.69 pg appeared. The most informative turned up to be the relative genome size of sperm cells n = 13+X1X2 and n = 13+Y, where specimens with higher chromosome number showed...
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