When the president looks at an anti-alien protest on TV, the actual footage is from a pro-independence Catalan protest in Spain. You can clearly see the Catalan flags.
Menagerie is a name shared by two anti-heroines in the DC Universe, both members of The Elite. The two are Puerto Rican sisters who are linked with a symbiotic alien weapon crèche called symbeasts. Pam first appears in Action Comics #775 (March 2001). While the origins of her powers are unclear in Action Comics #775, Manchester Black states that the rogue Men in Black (from the Department of Extranormal Operations) once picked up the dregs of society, turning them into weapons and selling them off to the highest alien bidder. Black recruits Pam to be a member of the Elite, Sonja first appears in JLA #100 (August 2004).
Interestingly enough, the original version of Menagerie from DC Comics was inspired by Venom, but the character was meant to be a parody rather than an outright rip-off. First appearing in Superman #775 in March 2001, Menagerie was part of a new superhero team called the Elite who challenged Superman's morality by claiming that they were the better heroes because they would use lethal force if they had to. Superman tried to teach the Elite a better way, before ultimately facing the entire team in a duel where he proved that he could subdue them all without violating his ethics. Now considered to be one of the greatest Superman stories of all time, the issue was later adapted into an animated movie, Superman vs. the Elite.
The fear of, or aversion to, snakes is called ophidophobia, and is a sub-class of herpetophobia, the fear of, or aversion to, reptiles.
This episode shares many similarities to the marvel villain and movie Venom, though his symbiote expressed a preference for brains over hearts. The episode also depicted Pamela referring to herself and the symbiote in the plural ("We... are... Menagerie!"), the symbiote communicating with Pamela as a raspy voice only she could hear and the symbiote manifesting as a series of snake-like tentacles .