Perhaps under keys will be a better option may be looking at those specimen images?

S. dohertyi
unh discal spots are separated from the dark border (Evans, 1949)?
https://www.ifoundbutterflies.org/me...11/a-28777.jpg


S. sambara
Unh discal spots are more close to the dark border?
https://www.ifoundbutterflies.org/me...11/a-28780.jpg

Cheers