[1] The southern rubber boa, also known as Charina umbratica, has been proposed as an independent species because of its morphological and geographic differences.

[8] As of April 2017, the southern rubber boa was listed as a state threatened species in the California Natural Diversity Database.

[10] The southern rubber boa is known to typically inhabit areas such woodlands and coniferous forests characterized by their developed soils and great vegetative productivity.

The southern rubber boa makes use of outcrops, loose and developed soils, as well as tree-debris to burrow and seek refuge.

Phylogenetic analyses have conclusively distinguished northern and southern boas and identified an area in Northeastern California containing populations of both subspecies.

In April, female boas typically emerge from hibernation under reproductive conditions; mating occurs immediately and persists through May.