With our current state of knowledge of bee fly systematics, some groups are barely known below the generic level. Most noteworthy locally is the genus Villa. Although it is well-described, with at least 50 taxa cited for the Nearctic Region (Hull 1973), few are reliably figured anywhere, dichotomous keys are lacking, and descriptions are often sketchy and, relying on different characteristics, lack congruity between authors. The number of regional species is likely in the dozens, yet only a handful can reliably be identified and thus be included in this website. Several other genera are a notch better; i.e., Apolysis, Geron, Neacreotrichus, and Poecilognathus, but identification below the genus level sometimes involves considerable guesswork. Even well-described genera, some with layers of specific descriptions, keys, genitalic drawings, and other figures, may lack the characteristics necessary for a convincing species level identification. Examples include Aphoebantus and its relatives, Paravilla, Exoprosopa, and Poecilanthrax. What we have done in our endeavor here is to assemble the more common, more widespread, and more easily deciphered regional taxa, typically the ones for which we have specimens on-hand, and/or high-quality images from each genus. These are figured and described, their SE Arizona counties are listed, and seasonal occurrence is noted. If available, venational quirks and behavioral oddities are figured or discussed. All these informational tidbits are starting points--crumbs to assist future researchers in their investigations.