Kutz, SusanGomes Verocai, Guilherme2015-05-012015-06-222015-05-012015Gomes Verocai, G. (2015). Contributions to the Biodiversity and Biogeography of the Genus Varestrongylus Bhalerao, 1932 (Nematoda: Protostrongylidae), Lungworms of Ungulates, with Emphasis on a New Nearctic Species (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/25450http://hdl.handle.net/11023/2222Explorations of parasite biodiversity and biogeography are essential for elucidating evolutionary and ecological patterns and processes that shaped the biosphere. Among relevant nematode parasites of ungulates are species within the family Protostrongylidae Leiper, 1926 (Strongylida: Metastrongyloidea), which often cause pulmonary, muscular or neurological diseases in their hosts. The finding of a novel protostrongylid species infecting North American ungulates in 2007 demonstrated that the knowledge of the biodiversity of this group remained incomplete, despite the substantial advances in recent decades. Through my thesis research I focused on developing and understanding the biodiversity, phylogenetic relationships, and biogeography of the genus Varestrongylus Bhalerao, 1932 (Nematoda: Protostrongylidae), lungworms of cervids and caprine bovids. To do this, I first explored the validity of existing species, and have resurrected and redescribed Varestrongylus alces Demidova & Naumitscheva, 1953 of the Eurasian moose from Europe. Secondly, I described Varestrongylus eleguneniensis Verocai, Kutz, Simard & Hoberg, 2014. This new species primarily infects caribou, but also muskoxen and, rarely moose across a vast range in North America. By exploring the relationships among Varestrongylus species, I have developed a phylogenetic hypothesis for the genus and for co-evolution and biogeography of this host-parasite assemblage. Varestrongylus has a complex history, characterized by multiple events of host-switching and geographic expansion. Moreover, through a geographically wide assessment of the distribution of V. eleguneniensis in caribou, muskoxen and moose populations across North America I have established baselines for future studies monitoring the geographic distribution of a lungworm species. This work also provides a foundation for understanding historical and current processes affecting the biogeography of host-parasite assemblages. The present work is an original contribution to the field by adding to the present knowledge on taxonomy and biodiversity of this relevant group of parasites, to the general understanding of the formation of host-parasite assemblages, and the colonization of North America by both parasites and hosts. Ultimately, by understanding the historical and contemporary processes that have lead to current biogeography of V. eleguneniensis, this work can be used for predicting future trends on the distribution, host-associations and biogeography of V. eleguneniensis under a scenario of rapid climate change.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.ParasitologyParasite biodiversityBiogeographyParasitologyUngulatesNematodaProtostrongylidaedoctoral thesis10.11575/PRISM/25450