They are certinly kaouthia. even normal phase atra are near non exsistant in US collections or atleast were 5 yrs back when I was keeping Naja.

Formosa is a bogus name if i recall correctly. These kaouthia are not a local varient like some may lead you to belive. They are simply an abarent form of naja kaouthia though i do admit it has been several years since I discussed this and may have my facts alittle mixed up.