I'm a land snail guy, but also a retired lawyer and a nerd on the Rules of Zoological Nomenclature.
Your mention of S. d. k. ethylae raised a question in my mind: was the name published as an infrasubspecific taxon, thus raising the question of whether the name was properly published for purposes of zoological nomenclature (see Art. 45.5 and 45.6 of the Code). The name doesn't show up in MolluscaBase.
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