Thesis (Ph. D.)--University of Wisconsin--Madison, 1999. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 308-344).

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To determine if temperature and water conservation/collection play a significant role in the success of feral honeybees, experiments in foraging behavior, temperature tolerance, water balance, hemolymph osmolality regulation and uric acid concentrations of both feral and domestic bees were conducted. This study shows that feral honeybees collect larger volumes of liquid and have higher critical thermal maxima (CTMs) than domestic honeybees. Feral bees may need more liquid for thermoregulation than do domestic bees. The rate of water loss did not differ significantly between the two types of honeybees. Hemolymph osmolality was slightly significant lower in feral bees. In response to desiccation, both feral and domestic bees showed reduced concentrations of proteins and amino acids in the blood. Therefore both types of honeybees maintained hemolymph osmolality during desiccation. There were no differences in mean concentrations of uric acid in feral vs domestic bees and no difference as a result of desiccation. This indicates that uric acid is regulated but is not an osmoeffector.

Laboratory tests conducted to evaluate the ability of three formamidines (chlordimeform, amitraz, and N'-(2,4-dimethylphenyl)- N-methylformamidine SN-49844, a metabolite of amitraz) to synergize permethrin in tobacco budworm (TBW) showed no synergism in susceptible larvae, but did show synergism in resistant larvae. Chlordimeform (CDF) and N'-(2,4-dimethylphenyl)-N-methylformamidine SN-49844 showed higher degrees of synergism than amitraz. Selection of cross-bred larvae of tobacco budworm using permethrin ± formamidine mixtures at LD 80 for four generations produced strong tolerance to all agents used in the selection. A test for cross-resistance to cypermethrin and to methyl parathion in a permethrin-selected strain of tobacco budworm showed resistance levels of 58-fold, and 48-fold, respectively, compared with susceptible TBW.

The Turtle Ant, Zacryptocerus rohweri, is an arboreal, polydomous ant commonly nesting in the dead branches of Palo Verde. Colonies are small with a dimorphic worker caste. Their diet was observed to be primarily liquid, but pollen may also be important. Behavioral studies revealed a high degree of both oral and abdominal trophallaxis. The morphology of the digestive tract of Z. rohweri is also described. The proventriculus is covered with clusters of small spines which act as a fine filter of food. Ultrastructural study reveals bacteria amongst the microvilli of midgut epithelial cells. The hindgut consists of an enlarged pouch filled with large masses of bacteria of three major morphotypes. Newly emerged individuals appear to acquire these microorganisms through abdominal trophallaxis of older workers in the colony. The hypothesis that abdominal trophallaxis is a means of transferring hindgut bacteria which may add important nutrients to their limited diet is proposed.

The Corinnidae is one of 76 families of spiders (Arachnida: Araneae) presently recognised in the Afrotropical Region. By the end of the last century their taxonomy and systematics had been very poorly studied and no modern revisions existed on the group. At that time, 110 species in 22 genera were known from the region, making it a family with moderate species richness. The description of the new genus Hortipes Bosselaers & Ledoux, 1998 in the family Liocranidae signalled the start of modern systematics studies in that family, and following the transfer of Hortipes to the Corinnidae, of that family by default too. Since that time, 20 taxonomic papers have been published on the Afrotropical Corinnidae and 10 new genera (all endemic to the region) and 164 new species have been described, of which three species form part of the current study (Chapters 7 and 9). Several genera have also been transferred to or from the Corinnidae in those papers. Presently there are 35 genera and more than 270 species known from the region, with the Corinnidae now ranking eighth in species richness in the region. Most of the revisionary work so far has focused on the subfamilies Trachelinae and Phrurolithinae, while the Corinninae sensu lato and Castianeirinae have largely remained neglected. The broad aim of the current study was to focus on the systematics of the latter group, treat the taxonomy of each of the currently known genera, at least in part, and provide a basis for future work on the subfamily. As such, many of the smaller genera in the subfamily were revised in the Afrotropical Region and two new genera were described. The genus Apochinomma Pavesi, 1881, the only described genus of accurate antmimicking castianeirines from the region, is revised and separated into two species groups based on genitalic and abdominal morphology. The type species, A. formicaeforme Pavesi, 1881, is redescribed and three new species are described in the A. formicaeforme species group: A. malkini sp. nov., A. parva sp. nov. and A. tuberculata sp. nov.. Two new species, A. decepta sp. nov. and A. elongata sp. nov., are described in the A. decepta species group, although an additional species only known from juveniles can also be placed in the latter group. Members of the A. formicaeforme species mimic Polyrhachis ants and are mainly arboreal, while members of A. decepta species group are ground- or grass-dwelling and probably mimic ponerine ants. The genus Cambalida Simon, 1909 is revised and three species are transferred from Castianeira Keyserling, 1879 to Cambalida: C. deminuta (Simon, 1909) comb. nov., C. fulvipes (Simon, 1896) comb. nov. and C. loricifera (Simon, 1885) comb. nov.. An additional species is transferred from Brachyphaea Simon, 1895 to Cambalida: C. fagei (Caporiacco, 1939) comb. nov.. All of these species are redescribed, as is Cambalida coriacea Simon, 1909. Two species, Castianeira depygata Strand, 1916 syn. nov. and C. mestrali Lessert, 1921 syn. nov., are considered junior synonyms of C. fulvipes. The type material of the type species of the genus, C. insulana Simon, 1909 from Annobon Island, is lost, and only immature specimens have been subsequently collected from a nearby island. The species is regarded as a nomen dubium until fresh adult material can be collected. A replacement name, Cambalida simoni nom. nov., is proposed for Cambalida fulvipes Simon, 1909, the latter being a secondary junior homonym of Cambalida fulvipes (Simon, 1896) comb. nov.. The type material of C. simoni is also lost and it too is considered a nomen dubium. Five new species are described: C. compressa sp. nov., C. dippenaarae sp. nov., C. griswoldi sp. nov., C. lineata sp. nov. and C. unica sp. nov.. Castianeira Keyserling, 1879 is the largest genus in the Corinnidae with 131 described species, of which 22 are presently known from the Afrotropical Region. There is a very rich undescribed fauna known from the region, and the variable morphology of its component species would suggest it is polyphyletic and should be divided into several genera. For example, six species are misplaced and have been transferred to or synonymised with species in Cambalida or the new genus Copuetta gen. nov.. In the present study, five species are redescribed and illustrated for the first time based on the type material: C. delicatula Simon, 1909, C. formosula Simon, 1909, C. majungae Simon, 1896, C. phaeochroa Simon, 1909 and C. thomensis Simon, 1909. The female holotype of C. bicolor (Simon, 1890) lacks an abdomen and the species is considered a nomen dubium. The types of several Afrotropical species could not be traced as yet and the species should be redescribed, if possible, based on recently collected material from near their type localities. The ground-dwelling genus Copa Simon, 1885 is one of four genera in the Afrotropical Region that have cryptic colouration that bears a resemblance to that of wolf spiders (Lycosidae), hereafter referred to as cryptic lycosiform colouration. The type species of the genus, C. flavoplumosa Simon, 1885, is redescribed and proposed as a senior synonym of C. benina Strand, 1916 syn. nov. and C. benina nigra Lessert, 1933 syn. nov.. This is possibly the most widespread corinnid in the Afrotropical Region albeit that is has not yet been recorded from any of the islands. A new species, C. kei sp. nov., is described from South Africa. Copa agelenina Simon, 1910, originally described from a subadult female from southern Botswana, is considered a nomen dubium. Although the Madagascan fauna was not included in this revision, nearly 30 new species have been distinguished from museum collections, and once that fauna is revised it will provide an exceptional example of island radiation. In a revision of the Afrotropical species of the ant-mimicking genus Corinnomma Karsch, 1880, Apochinomma semiglabrum Simon, 1896 is redescribed from both sexes, and based on these descriptions it is transferred to Corinnomma as C. semiglabrum (Simon, 1896) comb. nov.. A new species, C. lawrencei sp. nov., is described from Mozambique, Tanzania and South Africa. The taxonomic status of C. olivaceum Simon, 1896 is discussed and the first illustrations of the female genitalic structures are presented. Since no fresh material of this species is available and the female holotype is badly faded, it is not thoroughly redescribed. An English translation of Simonâs (1896) Latin description of C. olivaceum is provided with the intention of more accurately describing the colouration of this species. The arboreal cryptic lycosiform castianeirine genus Echinax Deeleman-Reinhold, 2001, previously known only from South-East Asia, is recorded from the Afrotropical Region for the first time. Copa longespina Simon, 1909 is redescribed and the species is transferred to Echinax as E. longespina (Simon, 1909) comb. nov.. Six new species are described from both sexes: E. clara sp. nov., E. hesperis sp. nov., E. natalensis sp. nov., E. scharffi sp. nov., E. similis sp. nov. and E. spatulata sp. nov.. The genus Graptartia Simon, 1896, presently known only from Africa, is revised. The type species, G. granulosa Simon, 1896, is redescribed and the first genitalic sketches of the species are provided. Two new species, G. mutillica sp. nov. and G. tropicalis sp. nov., are described. Unique amongst African castianeirines, all species of Graptartia are mimics of wingless female velvet ants (Mutillidae). Although the genus Merenius Simon, 1909 is not revised, a single common species, Merenius alberti Lessert, 1923, is redescribed. The species was previously known only from South Africa, and is recorded for the first time from Mozambique, Swaziland and Zimbabwe. While most populations of M. alberti comprise the typical black morph of the species, a red morph is described for the first time here. As part of a field study to identify the potential models of the two colour morphs of M. alberti, spiders were collected by hand and ants by pitfall trapping in the Ndumo Game Reserve in northern KwaZulu-Natal, South Africa. The ants assemblages sampled at 20 sites in the reserve seem to indicate that the black morph is a generalised mimic of black ground-dwelling ants, most likely Camponotus cinctellus (Gerstäcker, 1859), Streblognathus peetersi Robertson, 2002 and Polyrhachis gagates F. Smith, 1858, while the red morph is a mimic of Anoplolepis custodiens (F. Smith, 1858) ants. are inadequate to support any systematic changes in the Corinnidae, but future analyses need to include a more diverse range of castianeirine genera from outside the Afrotropical Region to better understand the relationships of the Afrotropical fauna. In the final chapter, the role of Castianeirinae as components of arthropod mimicry complexes is described for three species of ants, Anoplolepis custodiens (F. Smith, 1858), Polyrhachis gagates F. Smith, 1858 and Camponotus fulvopilosus (De Geer, 1778). There are respectively two out of 10, four out of six, and zero out of five species of Castianeirinae forming part of the arthropod complexes associated with these ants. All of these castianeirines are inaccurate (weak/ generalised) mimics of their models except for Apochinomma formicaeforme, which is an accurate (good/specialised) mimic of P. gagates. Colour polymorphism is also described for the first time in four species of Afrotropical Castianeirinae, i.e. Corinnomma semiglabrum, Merenius alberti, Castianeira cf. venustula (Pavesi, 1895) and Copa flavoplumosa. Three of these species are inaccurate mimics of ants, while C. flavoplumosa is a species with a widespread variant with cryptic lycosiform colouration and a nigrito form restricted mainly to tropical forests. High Castianeirinae biodiversity and endemism corresponds to most of the main Biodiversity Hotspots and Centres of Endemism (CE) in the Afrotropical Region: Maputaland-Pondoland-Albany CE (five endemics), Madagascar and Indian Ocean Islands CE (>30 endemics), East African Afromontane Forests CE (four endemics), East African Coastal Forests CE (five endemics), Guinean Forests of West Africa CE (seven endemics) and the Horn of Africa CE (one endemic). No endemic castianeirines have been recorded in the Succulent Karoo and Cape Floristic Region CEâs in southern Africa, although this corinnid fauna of these two CEâs is largely dominated by Trachelinae, most of which are endemics.

The study of blood parasites of reptiles is a relatively new and unexplored field in South Africa. Therefore, the general aims of this research were to explore the haemoparasite fauna of cordylid lizards, Pseudocordylus melanotus, Pseudocordylus subviridis and Pseudocordylus langi, and especially to search for the definitive hosts and likely vectors of their haemogregarines. Surveys of lizard blood were conducted at various altitudinal gradients on the Sentinel Trail in the escarpment area of the Drakensberg, and at the top of Platberg, near Harrismith, both in the Free State. Five species of haemogregarines were identified, all suspected to belong to the genus Hepatozoon, and none was known from previously published records. These occurred in the blood of P. melanotus, P. langi and P. subviridis from the two disjunct study sites, and mostly were accompanied by other haemoparasites including a saurian malaria, so-called Sauroplasma, and filarial nematodes. Developmental stages of two of the Hepatozoon spp. were documented in the internal organs of P. melanotus and P. subviridis by means of light and confocal microscopy, histology, and transmission electron microscopy. Life stages were also observed in ectoparasitic lizard mites, by means of stained histological sections, and in stained squashes of mites and mosquitoes. Three species of experimentally reared mosquitoes were found to act as likely definitive hosts for Hepatozoon spp. of P. melanotus and P. subviridis, while wild caught Culex (Afroculex) lineata appeared to serve as a definitive host, and therefore possible vector for an Hepatozoon species of P. melanotus at the top of Platberg. A saurian malaria that appeared to have features of two previously described species was recorded in P. melanotus and P. subviridis. New locality records for so-called Sauroplasma and filarial nematodes were also documented for the three species of crag lizards. Some aspects of the fine structure of two haemogregarines, the Plasmodium sp. and so-called Sauroplasma infections were recorded for the first time in the erythrocytes of the Pseudocordylus spp. Differential leucocyte and thrombocyte counts were performed on the three crag lizard species and, with erythrocyte characteristics, compared with those of cordylid lizards in previous studies. Several types of leucocytes were characterized ultrastructurally, as well as by light microscopy, and attempts were made to correlate statistically leucocyte counts, and host and environmental data, with parasite loads. Finally, mites and mosquitoes associated with crag lizards were explored further as possible vectors of lizard haemoparasites, and studied using light and scanning electron microscopy.

Culicoides midges are involved in the transmission of a variety of pathogens, the most economically important of these are the orbiviruses that cause African horse sickness (AHSV) and bluetongue (BTV). The identification of vectors of these viruses and monitoring of their occurrence and activity plays an important role in the control measures and disease risk analysis. The primary tool used for monitoring these midges through collection is various models of light traps. In order to standardise collection data to be comparable between laboratories, a variety of factors that affect the light trap collections were assessed. Comparisons of different light traps (Onderstepoort trap and the Free State trap), the influence of light colour, trapping height and the distance a trap is operated from the host animals were assessed. Comparisons were done using either three replicates of a 4 x 4 or two replicates of a 6 x 6 randomised Latin square design. The most significant variables were the trap type, with the Onderstepoort trap collecting significantly more Culicoides than the Free State trap, and the sampling distance from the host animals. The proportion of C. imicola (the most frequent species collected) was the highest when collected right next to host animals and decreased rapidly as collections moved further from host animals. Trap height also proved to be an important variable, although no significant differences were observed when collecting midges at two metres to three metres above the ground. The occurrence, abundance and seasonality of the midges frequenting livestock in the central Free State were also assessed by collecting midges using light traps over a four-year period from April 2007 up to May 2010. Twenty Culicoides species were collected, the most abundant and important species was C. imicola, a confirmed vector of both the AHSV and BTV. The midges showed a distinct seasonal pattern, but were also collected year round, identifying periods of high risk, as well as a year-round risk of disease transmission. The midge populations almost disappeared when temperatures dropped during the winter months, the build-up and abundance during favourable conditions, however, indicated a high risk for disease transmission. Culicoides imicola also showed a considerable preference for livestock animals when assessing collections made near horses sheep and cattle as opposed to collections made in the absence of livestock host animals. An effort was made to identify possible breeding sites of Culicoides species. No midges were, however, collected in the tent type traps or the dung and soil samples collected and placed in emergence boxes. This again emphasised the diversity of the midgesâ breeding habitats and the enormous task still ahead to identify these sites to aid in possible reduction of midge numbers.

Equine piroplasmosis is a protozoan disease of horses caused by two parasites, Babesia caballi and Theileria equi. Both parasites are transmitted by ixodid ticks belonging to the genera Boophilus, Hyalomma, Dermacentor and Rhipicephalus. Equine piroplasmosis has a worldwide distribution and is endemic in tropical and sub-tropical regions, including Central and South America, Africa, Asia and Southern Europe. The economic impact of equine piroplasmosis in South Africa is assumed to be millions of Rands due to a combination of direct losses, convalescence period and incidental costs such as vaccinations, treatment and veterinary fees. There is little information on parasite strains in South Africa. The objectives of this study were to determine (i) the prevalence of equine piroplasmosis in Free State (FS) and KwaZulu Natal (KZN) of South Africa, using molecular and serological techniques, and (ii) strain variation of equine piroplasmosis parasites, namely, B. caballi and T. equi, using 18S rRNA DNA sequences analysis. Diagnostic methods used in this study include microscopy (thin blood smears), Polymerase Chain Reaction (PCR), Indirect Fluorescent Antibody Test (IFAT) and Enzyme-Linked Immunosorbent Assay (ELISA). Blood samples were collected from a total of 534 horses in the Free State and KwaZulu-Natal (444 were collected from FS and 90 from KZN). No B. caballi was detected from all samples collected from both provinces (FS and KZN) by microscopy and PCR. Of 507 serum samples tested for B. caballi by IFAT, a seroprevalence of 61% was detected. A mean value of 34% of samples was positive for T. equi using a PCR test and sero-prevalence of 94% was detected by IFAT. Fifty two percent of the 250 tested sera samples were positive for T. equi by ELISA. Together these results suggest high levels of exposure to parasites, high levels of current infections and uncertainty in current serological tests for these parasites. Sequencing and phylogenetic analysis of the 18S rRNA gene showed considerable diversity of T. equi strains in South Africa. T. equi is highly prevalent in South Africa with the parasite appearing to be more prevalent in KZN than FS. This study also confirmed the distribution of this disease as described in previous studies, and the disease was found also in the area which previously was declared disease-free. There is considerable variation in T. equi genotypes in the country and no clear phylogeographic structuring of these genotypes. These results may indicate that there is much movement of infected carrier horses within the country and even to and from other countries. B. caballi prevalence is still not clear as only IFAT seems to detect antibodies to infection by this parasite. There is a need for the development of highly sensitive assays for the detection of B. caballi, thereby enabling determination of prevalence and strain diversity studies of this parasite.