The southern African species of the Aradidae subfamily Carventinae are revised, resuhing in the recognition of 7 genera, 24 species and 10 subspecies (excluding the nominal ones). Of these, 4 genera, 18 species and 10 subspecies are described as new. A neotype is designated for Dundocoris natalensis. Keys to the genera and species are given. Scanning electron photomicrographs of the dorsal and ventral aspects and external genitalia are provided for all the species. The cytogenetics of the group are discussed and idiograrns, based on chromosome area measurements, and photomicrographs of meiotic stadia (mostly metaphase I and metaphase II) are presented for all but one species. The chromosome numbers of the species vary between 2n = 7XY1Y2 and 2n = 32XY and XY, X1X2Y and XY1Y2 sex chromosome systems occur. Muhiple sex chromosome systems that originated from autosome-sex chromosome fusions are described for the first time in the Heteroptera. A unique case where two homologous autosomes have fused with the X- and Y -chromosomes respectively, is reported. Karyotype evolution and the origin of the different chromosome numbers are discussed and hypotheses presented. Pseudoploidy, fusions and to a lesser extent fragmentation, have played the major role in the karyotype evolution of the Carventinae. The cytogenetics of the other subfamilies of the Aradidae are briefly discussed and illustrated. It is argued that the ancestral chromosome number for the Carventinae and Aradidae (and therefore also the Pentatomorpha) is 2n = 14XY. The morphological and cytogenetic data are integrated in the classification of the Carventinae and several of the subspecies are based on chromosome number differences. The homeostatic genetic species concept is proposed and its application to the Carventinae is discussed. Phylogenies for the genera and species are proposed. The text is accompanied by more than 540 figures and more than 60 tables. / Thesis (DPhil (Entomology))--University of Pretoria, 2007. / Zoology and Entomology / unrestricted

Taxonomic changes are made based on checkered beetle (Coleoptera: Cleridae) types of the Natural History Museum, London (BMNH).Lectotypes are designated (and holotypes and paralectotypes recognized) for 44 species of Hydnocerinae, including the type species for Isolemidia, Parmius, Paupris, Allelidea, Blaesiopthalmus and Lemidia, four species of Enoclerus (Clerinae), and 14 species of Cymatodera (Tillinae). Annotations include comments on additional type material, new type locality, previous (type series) locality, and questionable or missing types. Phyllobaenus pallipes(Gorham) and P. rufithorax (Gorham) are synonymized with P. flavifemoratus(Gorham), P. chapini (Wolcott) is synonymized under P. lateralis (Gorham), and P. villosus (Schenkling) is synonymized under P. longus (LeConte), new synonymies. The first molecular phylogeny of the clerid lineage (Coleoptera: Cleridae, Thanerocleridae) is presented and compared with the two most recent phylogenetic hypotheses of the group. Phylogenetic relationships of checkered beetles wareere inferred from approximately 5,000 nucleotides amplified from four loci (28S, 16S, 12S, COI). A worldwide sample of ~70 genera is included and phylogenies are reconstructed using Bayesian Inference and Maximum Likelihood. The results are not entirely congruent with either of the current classification systems. Three major lineages are recognized. Tillinae are supported as the sister group to all other subfamilies, whereas Thaneroclerinae, Korynetinae sensu latu and a new subfamily formally described here, Epiclininae, new subfamily, form a sister group to Clerinae + Hydnocerinae. To assess the phylogeny and evolution of Hemiptera, a comprehensive mitogenomic analysis integrating mitogenome-based molecular phylogenetics, fossil-calibrated divergence dating (using BEAST), and ancestral state reconstructions are presented. The 81 sampled mitogenomes represent the most extensive mitogenomic analyses of Hemiptera to date. The putatively primitive “Homoptera” was previously rendered paraphyletic by Heteroptera, whereas the presented results support each group as monophyletic. The results from both diet and habitat ancestral state reconstructions support that 1) Heteroptera (and Homoptera) evolved from a phytophagous ancestor, contrary to the popular hypothesis that the ancestor was predaceous; and 2) family-level radiation of Heteroptera is coincident with the apically-produced labium and the novel hemelytron. It is here proposed these morphological innovations facilitated multiple independent shifts from phytophagy to predation and multiple independent colonizations of aquatic habitats.