Question
The moonflower I have has serrated leaves longer than a dandelion & the petals are pale yellow & larger, not at all like the Texas dandelion you showed. I had my plant given & it seems to be spreading. I would love to know it's real name everyone I know just calls it a moonflower.
     Thanks

Answer
Hi Brenda,
Thanx for your question. There is a yellow flower called the evening primrose that some people refer to as a moonflower.  Moonflower is a term used for a lot of different flowers.  Look at the link below and let me know if this is the plant.  It has a spreading habit too.  It is also hardy to Zone 5, possible warmer parts of Zone 4.

http://livingafield.com/images/Evening_Primrose_01.jpg

I hope this helps.
Tom