Thanks to both of you, I'll have to agree. Can't figure out where it came from though. I had some Oleander growing around the side of the house next to the fence but they died from either not enough sunlight or water. They were on the east side so didn't get full sun all day long. This one was growing next to one of my Lantana plants. Well, it's in a pot now and I can mark it as Oleander.
Thanks again, much appreciated.