Complex sentence: Making it even more confusing, in the U.S. it is sometimes called "Graham's sage" because it was once described as "Salvia grahamii" by George Bentham, who didn't know it had previously been named as "S. microphylla".
Split into simpler sentences: Making it even more confusing, in the U.S. it is sometimes called "Graham's sage". It was once described as "Salvia grahamii" by George Bentham, who didn't know it had previously been named as "S. microphylla".