Here is a link to the ICZN (International Commission on Zoological Nomenclature) where they stepped in to stop a proposed name change to T.s.tetrataenia (San Francisco Garter Snake) in order to keep its "Endangered" status intact.

Conservation | International Commission on Zoological Nomenclature

Here is another link to a study that shows T.s.tetrataenia has a much larger range then O'Shea suggests.
Thank you Steve Schmidt for the link to this study.
http://ecos.fws.gov/docs/five_year_review/doc774.pdf