What specific soil condition is consistently required by *R. humilis* for successful burrowing and foraging?
Loose soil, such as sandy deposits or gravelly alluvial fans
Despite inhabiting arid zones, the Western Blind Snake does not inhabit all desert lands equally; it has strict requirements regarding the physical structure of the substrate to support its fossorial existence. The necessary condition across various regional accounts is the presence of loose soil. This facilitates the snake's ability to dig efficiently and move through its environment. Examples of preferred substrates include sandy soils or gravelly deposits found in alluvial fans. Conversely, the text notes they are seldom found in environments that are too consolidated, specifically mentioning strictly sandy areas or dry lake beds, which likely lack the necessary structure for easy burrowing or sufficient subsurface moisture retention.
