Project Abstract: This project has as its primary goal to taxonomically revise and study the evolutionary relationships of the trapdoor spider subfamily Euctenizinae (Cyrtaucheniidae). Alpha-taxonomy is a field of biology that provides the underlying foundation, and thus lies at the very core, of almost every biological question; revisionary-systematic studies are one of the more powerful tools we can apply to the study and conservation of our planet's biodiversity. Although North America has a rich tarantula and trapdoor spider fauna it is shocking that 50% of these species remain undescribed and that much of this diversity, attributable to members of the Euctenizinae, is distributed throughout the California Floristic Province, an evolutionary center that is a biodiversity "hotspot". This project proposes to formally document euctenizine diversity by completing exhaustive taxonomic revisions of all of its genera and species (70 - 80) and by then reconstructing its species evolutionary relationships using morphological, behavioral, and molecular data. Because this project "utilizes modern information technology at all stages" (e.g., GIS, digital imaging, sequence data generation and alignment, and phylogeny reconstruction) it is ideal for training students in the methods and concepts surrounding modern revisionary work. Students as full partners in research will be trained to gather and analyze taxonomic and phylogenetic data, and will be encouraged to present their results at meetings and as scientific journal publications. Fieldwork conducted during the course of this project will result in the acquisition of many rare specimens that will be deposited in major museum collections for future study. Data generated from these specimens will be made available on the World Wide Web as part of a project website. Additionally, this project will make available interactive, fully illustrated taxonomic keys to all of the known Euctenizinae species that can be then used by non-spider specialists. http://www.nsf.gov/awardsearch/showAward.do?AwardNumber=0315160