Search

The Eucalyptus gall wasp, Ophelimus maskelli, is a significant pest in areas throughoutthe world. Heavy galling significantly weakens trees as well as causing early defoliation leadingto premature death. Eucalyptus species are grown all over the world for various uses includingfuel and paper making. The plants are especially prized in plantations for their rapid growth anddevelopment. O. maskelli was recently discovered in southern California along with twoassociated parasitoid wasps. Closterocerus chamaeleon is a known parasitoid of O. maskelli andhas been intentionally introduced in areas of Israel as well as throughout the Mediterranean foruse as a biological control agent. The second parasitoid wasp, Selitrichodes neseri, has beenintentionally introduced in South Africa as a biological control agent for another Eucalyptus gallwasp, Leptocybe invasa. Phenologies of each species in southern California are recorded anddiscussed using two different collection methods. Comparisons are made between species,inland and coastal populations of southern California, and populations in Israel. Morphological,molecular, and ecological data are combined in the description of a new strain of S. neseri insouthern California. Our studies discuss ecological relationships between these three waspspecies as well as provide a groundwork for further research involving the adjustment ofinvasive species to a new environment.

Parasitoid wasps are hyperdiverse, with current estimates suggesting that they may account for up to 20% of all insect species. Though their ecological significance and their importance in integrated pest management cannot be denied, these taxa remain understudied and, due to their small size, are often overlooked. However, recent advances in molecular techniques are helping to reverse this trend by providing tools which scientists can use to better understand species limits and host interactions. Parasitoid wasps are often morphologically cryptic and their accurate delimitation requires the analysis of DNA sequence data from fast-evolving genes in addition to morphological characters. The research presented here demonstrates the utility of a new molecular locus in species delimitation. Also, a morphological key to the species of a genus occurring in America, north of Mexico is presented. The interactions between parasitoid wasps and their hosts are highly complex. On the wasp side, it involves the production venom, which likely contains bountiful natural resources. In this study, the venom proteins of wasps of the genus Megarhyssa (Hymenoptera: Ichneumonidae) are identified. Putative functions are assigned to these proteins and possible applications are discussed. One of the proteins identified is the enzyme, laccase, which is associated with the degradation and digestion of wood. The sequence of the gene coding for this laccase was analyzed and used to create recombinant proteins in a baculovirus-insect cell expression system. Future work investigating this enzyme is necessary to determine its activity against the plant cell wall. The research presented here provides insight into the identification and venom composition of ichneumonid wasps. The results contribute to our knowledge of this understudied taxon and indicate that there is much to be gained from further research in this field which will become increasingly practicable as molecular techniques advance and become more affordable.

Parasitoid wasps are an important group of organisms in need of systematic revision. This dissertation examines the cosmopolitan parasitoid wasp genus Cremnops. It is a compilation of three projects and significantly advances the taxonomic foundation of the genus. The New World species of the genus Cremnops are revised. Thirty-three species of Cremnops are treated; five are described as new, i.e., C. bertae sp. nov., C. cluttsis sp. nov., C. nymphius sp. nov., C. wileycoyotius sp. nov. and C. witkopegasus sp. nov. Six species are synonymized, i.e., Cremnops caribensis Berta 1998, is synonymized under C. guanicanus Wolcott 1924; C. nigrosternum (Morrison 1917) is synonymized under C. haematodes (Brullé 1846); C. punctatus Berta 1998, is synonymized under C. marshi Berta 1998; C. sharkei Berta 1998, is synonymized under C. montrealensis (Morrison 1917); C. turrialbae Berta de Fernandez 1998, is synonymized under C. ferrugineus (Cameron 1887); and C. misionensis Berta 1987, is synonymized under C. slossonae (Morrison 1917). Cremnops florissanticola is transferred to its original combination Bracon florissanticola Cockerell 1919, st. rev. The species concept Cremnops desertor and its complicated taxonomic history are discussed. A phylogenetic distance tree, based on COI data, is used to help delimit species. The recognition of C. alterans Enderlein and C. malayensis Bhat is proposed. I propose new combinations for five African species that are currently placed in Cremnops, i.e., C. atripennis Szépligeti 1914 and C. elegantissima Szépligeti 1908 are moved to Disophrys; C. borealis (Szépligeti 1914) and C. rubrigaster Masi 1944 are moved to Biroia; and C. pulchripennis Szépligeti 1905 is moved to and renamed Biroia neopulchipennis. These changes result in Disophrys atripennis (Szépligeti 1915) becoming a junior homonym, which is changed to Disophrys szatripennis. Additionally, two species are proposed as nomen dubia: C. rufitarsis Szépligeti 1913 and C. schubotzi Szépligeti 1915. Included are a molecular phylogeny, a dichotomous key, links to distribution maps, an electronic interactive key, images of holotypes, and suggestions for further research.