Geographic variation and subspecific taxonomy of United States populations of the tiger beetle Cicindela obsoleta Say are reviewed. Study of primary types and 1,424 museum specimens indicates that four subspecific entities are present in the U.S., for which the valid names are C. o. obsoleta Say, C. o. santaclarae Bates, C. o. vulturina LeConte, and C. o. neojuvenilis Vogt. All four subspecies are illustrated, including many color variants. ArcView Geographic Information System (GIS) computer software is used to study the distribution of these subspecies in the United States. Cicindela o. obsoleta and C. o. santaclarae are only partially allopatric, with extensive areas in Arizona, New Mexico, and Texas where their distributions overlap. Specimens intermediate in their elytral markings between C. o. obsoleta and C. o. santaclarae are reported from localities in New Mexico and Texas where these two subspecies co-occur. In contrast, C. o. vulturina and C. o. neojuvenilis are largely allopatric and show little intergradation with the C. o. obsoleta - C. o. santaclarae complex. It has been suggested recently that disjunct (but as yet unnamed) populations of C. o. vulturina in Missouri and Arkansas may represent a separate subspecies of C. obsoleta. However, the color and elytral pattern characteristics which have been interpreted as diagnostic features of these disjunct populations are also found in many Texas populations of C. o. vulturina, suggesting that the Arkansas and Missouri populations do not merit recognition as a separate subspecies on the basis of these characters alone
