Agriculture Commons^™

Phylogeny And Population Genetic Analyses Reveals Cryptic Speciation In The Bombus Fervidus Species Complex (Hymenoptera: Apidae), Jonathan B. Koch, Juanita Rodriguez, James P. Pitts, James P. Strange

Ecology Center Publications

Bumble bees (Bombus Latrielle) are significant pollinators of flowering plants due to their large body size, abundant setae, and generalist foraging strategies. However, shared setal coloration patterns among closely and distantly related bumble bee species makes identification notoriously difficult. The advent of molecular genetic techniques has increased our understanding of bumble bee evolution and taxonomy, and enables effective conservation policy and management. Individuals belonging to the North American Bombus fervidus species-complex (SC) are homogenous in body structure but exhibit significant body color phenotype variation across their geographic distribution. Given the uncertainty of the genealogical boundaries within the SC, some …

South American Leaf-Cutter Bees (Genus Megachile) Of The Subgenera Rhyssomegachile And Zonomegachile, With Two New Subgenera (Hymenoptera: Megachilidae), Víctor H. González, Terry Griswold, Michael S. Engel

All PIRU Publications

Leaf-cutter bees (genus Megachile Latreille) are among the most common and diverse group of bees. However, the identity and taxonomic placement of many species are problematic and species identification is often difficult. Some species are known only from a single specimen or from one of the sexes, and identification keys are not available for many groups. We address these taxonomic issues for the subgenera Rhyssomegachile Mitchell and Zonomegachile Mitchell, two poorly known South American lineages of leaf-cutter bees. We provide comparative diagnoses, redescriptions, illustrated identification keys, new geographical records, and designate needed neotypes for Megachile cara Mitchell, M. gigas Schrottky, …

Dna Barcoding As A Tool For Species Discovery And Documentation In The Superfamily Ichneumonoidea, Sarah Meierotto

Theses and Dissertations--Entomology

Changes to traditional taxonomic methods to incorporate new technologies and methods have already improved the quality of species hypotheses, but more work can be done to improve the speed of new species documentation. The mitochondrial COI DNA barcode has been successfully used to identify species with high accuracy since the early 2000s, and has been used in conjunction with morphological examinations and other DNA markers to discover and delimit new species. This thesis explores the application of DNA barcodes as the primary data for delimitation and diagnosis of new species of ichneumonoids.

The genera Zelomorpha and Hemichoma are revised and …

Investigating Ichneumonidae: Insights Into Species Identification And Venom Composition, Victoria G. Pook

Theses and Dissertations--Entomology

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 …

Systematics And Biogeography Of Orthaea Kloztsch (Ericaceae: Vaccinieae), Nelson Salinas

Dissertations, Theses, and Capstone Projects

In the first chapter a study of the distribution patterns of the neotropical Vaccinieae (Ericaceae) is presented. Five areas of endemism were recovered: Central America, northern Chocó, southern Chocó, eastern Ecuador, and Yungas. Divergence times estimations indicate that the Andean clade of Vaccinieae migrated to South America during the Late Oligocene or Early Miocene (28.9-17.84 MA), and most of the subsequent diversification took place during the Tertiary. The Yungas was the first Andean area to be colonized, and several dispersals towards the north expanded their distribution range. Both areas of endemism and dispersal events were influenced by geological processes, such …

A Revision Of The New World And Select Old World Species Of Cremnops Förster (Hymenoptera: Braconidae: Agathidinae), Erika M. Tucker

Theses and Dissertations--Entomology

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 …

Systematics And Evolution Of Leandra S.Str. (Melastomataceae, Miconieae), Marcelo Reginato

Dissertations, Theses, and Capstone Projects

Phylogenetic studies in the Melastomataceae have demonstrated the need of taxonomic rearrangements in the current classification. Melastomes are among the most diverse groups of plants and several cases of known artificial taxa are observed and awaiting further resolution. One example is the Leandra s.str. clade, which includes the majority of the taxa traditionally treated in the genus Leandra. Some attempts have been made to infer the relationships of Leandra s.str., but the sampling in these earlier studies was sparse and the resolution low inside the clade. The main objective here is to propose a comprehensive phylogenetic framework for this group …

Porocercospora Seminalis Gen. Et Comb. Nov., The Causal Organism Of Buffalograss False Smut, Bimal S. Amaradasa, Hugo Madrid, Johannes Z. Groenewald, Pedro W. Crous, Keenan L. Amundsen

Department of Agronomy and Horticulture: Faculty Publications

False smut caused by Cercospora seminalis is an important disease of buffalograss (Buchloe dactyloides) affecting seed production. The pathogen prevents normal caryopsis development and causes considerable yield loss and reduced seed germination. The current taxonomic placement of the false-smut causal pathogen in the genus Cercospora is incorrect based on its morphological characteristics and DNA phylogeny. In the present study the phylogenetic position of C. seminalis is clarified based on DNA sequence analysis of three loci namely the internal transcribed spacer (ITS) region, partial nuclear ribosomal large subunit (LSU) and partial sequences of the RNA polymerase II second largest …

Identification Of Species Of Vicia Subgenus Vicia (Fabaceae) Using Chloroplast Dna Data, Nadia Haider, Imad Nabulsi, Nizar Mirali

Turkish Journal of Agriculture and Forestry

Vicia subgenus Vicia (Fabaceae) contains several economically important food and forage legume species. Generally, the taxonomy and identification of these species have relied heavily on a few diagnostic morphological characters (e.g., the number of flowers per inflorescence). However, there are several specimens with intermediate morphological characters that make diagnosis of these species using those characters a difficult task for nonspecialists and render results that are not always accurate. The use of molecular markers, therefore, is the most attractive alternative strategy for a more accurate identification of species of the subgenus Vicia. In the present study, an attempt was made to …

The Bumblebees Of Nebraska, Wallace E. Laberge, Morgan C. Webb

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

The purpose of this paper is to provide a ready means of identifying bumblebees found in Nebraska. It is for both amateur and professional entomologists. Included are an annotated list of the bumblebees found in Nebraska, artificial keys for species determination, a glossary for those not acquainted with the terminology used in the keys, a list of flower preferences and biological notes pertaining to bumblebees in Nebraska. The keys for identification include a few species of bumblebees which have not yet been collected in Nebraska but which may occur in the state.