[6] This study also confirmed strong genetic differentiation among the three subspecies aligning with geographic barriers.

A follow-up study using seven nuclear markers places S. ravus basal to all other members of the species complex.

[4] Found only in Mexico in the mountains in the center and south of the country, west of the Isthmus of Tehuantepec.

Its range includes the southeastern part of the Mexican Plateau in the highlands of Mexico, Morelos, Tlaxcala, Puebla, Veracruz, Oaxaca, and the Sierra Madre del Sur in Guerrero.

"[2] Campbell and Lamar (2004)[4] describe this species as being found across the Mexican Plateau in the temperate regions of moderate to high elevations.