Coins from the era* appear too depict Cleopatra as throughly european with her hair tied and knotted in a Hellenistic style known as a melon. Also her nose and eyes seem too lose any eastern appearance and become almost European, making her seem of a western descent is an easy way too make her less of a frightening prospect as queen to the Romans who I imagine would have been very intolerant of a woman gaining any kind of power.
Most of the stereotypes we know about Cleopatra come from roman sources, its almost as if the writers even two hundred or so years after actual events felt betrayed by Mark Antony, Cassius-dio writes about the pair with such venom that its almost impossible to think that he didn't have something of a personal bias against them.
It is these stereotypes that we go on to see in TV and film she is seen as a sexual predator that preys on the weaknesses of men and uses the latter for political gain, Cassius writes **"we the romans are the rulers of the greatest and best parts of the world and yet we find ourselves spurned and trampled open by a woman of Egypt" Its this example of misodgeny that illustrates the fundamental beliefs of a roman hierarchy at the time and the place of women in there society this is reflected in the film and TV portrayals of Cleopatra. Wherein they reflect there own small periods of history.
For example Theda-Bara's 1917 representation of the queen is much like her previous roles that of a fem-me fatal, this fitted well with morality at the time, powerful women are again something threatening and dangerous this combined with allure of an alien country like Egypt with its strange heliography and powerful pantheon of strange gods and goddesses were the perfect match, she made Cleopatra ominous and powerful but at the same time still accessible to a western audience. looking for thrills and the exotic.
In conclusion I am inclined to belive that the image presented of Cleopatra by the romans is used quite exclusively...