Unknown Lizards fighting No pics, No ID

Today while I was in the drive through I saw two rather large(10 inches long maybe?) brownish lizards have a territory type fight. They had knobs on the backs of their heads, and swollen looking ridges on their backs. I've never seen any lizard exactly like them, and was wondering if anyone had any ideas? If it had been possible I would have gotten pictures or captured them.
I tried googling and couldn't find anything even close. I'm in mid-north Florida, but I'm CERTAIN these weren't natives.
Wolfy

how are you CERTAIN?

Umm..
I lived here my entire life, and never saw them.
I've read up on reptiles of florida for the past two to three years, and never seen a picture nor read a description of these lizards.
In all my internet seeking I've never come across a lizard that seemed even remotely similar(other than being a lizard) to these as being in or near florida
That's why I said I am certain.
Any other questions?

I believe basilisks have been introduced into parts of Florida, might be your lizard.

John

From what I understand... Everything is thriving there! Giants, (as in Ticks and Burms) :rolleyes: All kinds of Parrots, Monitors.... CRAZY! :D

Looking up basilisks, they seem to be more pointed on the crest rather than rounded. Anyone know whether or not the young ones might not be pointed until they get mature or something? They were seriously weird looking, and I'm considering going back there to see if I can locate some of them.