Back in the 50s, at least two species of Brown Anole, from Cuba and the Bahamas, arrived in Florida, likely as stowaways on cargo ships, and began spreading. More arrived later from the pet trade, and there are now perhaps as many as eight different introduced species here. Crowding out the native Carolina Green Anole, the various types of Browns have interbred and hybridized extensively with each other (though it does not appear as if any of them are successfully hybridizing with the native Greens). Most of the Brown Anoles in Florida can no longer even be identified with any particular species or subspecies.
Some of their different appearances comes from the fact that, although they cannot change their skin color between brown and green like the native Carolina Anole, the various species of Brown Anole can voluntarily lighten or darken their skin to absorb more or less sunlight for thermoregulation. Also, some of the color differences are sexual: female Brown Anoles tend to have lighter zigzag strips running down their back, while males instead have rows of light spots running along their sides. But for the most part, the Brown Anoles in Florida today are a genetic mish-mash, and exhibit a wide variation in colors and patterns.
Male Brown Anoles also have a nuchal crest on the back of their neck that they can extend as part of their territorial display (along with their dewlap throat fan). Many, however, now also have a crest that extends along their back to the tail, which has probably been obtained through interbreeding with the introduced Crested Anole.
Since Anole Lizards are pretty famous for speciating at the drop of a hat (there are almost 450 different species), it is entirely possible that we are seeing the beginnings of several new species in Florida, as sexual selection may (or may not) lead each of these color variants to breed preferentially with each other and exclude the rest, eventually leading to separate gene pools.
Some examples of various colors and patterns I have seen around St Pete.