Actually, I know several spanish girls with the name 'Yesenia' (it is a type of tree).
It is in fact spanish, but it's origin is in Arabic. It became a spanish name when many arabs moved to spain (they were in control for a while) and their influences can be found in spanish archetecture aswell!!
I have been studying spain's history for the entire year and have been speaking the language since the age of 4, so I would appreciate no bashing on my thread!!
As the saying goes "if you don't have anything nice to say, don't say anything at all!"

If you still do not believe me beni, click this link here
and you will notice that most if not all of these sites categorize 'Yesenia' as a spanish name!