1. Department of Entomology, The Ohio State University , Columbus, OH 43214 , USA
2. United States Department of Agriculture, Agricultural Research Service, Pollinating Insect-Biology, Management, Systematics Research Unit , Logan, UT 84322 , USA
3. Raleigh , NC 27604 , USA
4. Department of Biology, Utah State University , Logan, UT 84322 , USA