Which species of recluse spider is predominantly located in the Southwest region of the United States?

The Desert Recluse is predominantly found in the Southwest region of the United States due to its specific habitat preferences, which include arid, sandy environments typical of desert regions. This spider thrives in warm climates and is adapted to living in places with low humidity.

In contrast, the Brown Recluse, while a notable member of the recluse family, has a broader geographical distribution, primarily found in the central and southern states but not specifically tied to the Southwest. The Black Widow, although a well-known spider, belongs to a different genus and is not categorized as a recluse spider, making it irrelevant to this question. The Western Recluse is a less common name that may refer to species in the western regions but is not as specifically associated with the Southwest as the Desert Recluse is.

The significant understanding here is that habitat and geographic distribution are key factors in identifying the Desert Recluse as the primary recluse spider in the Southwest.