1) Andorians / Aenar 2) Tellarites 3) Tholians 4) "Shroomie" aliens from the ep. "Silent Enemy" 5) Xyrillians
Andorians (kudos to Jeffery Combs - the quintessential Andorian) Orions (I'm glad the show filled in the Orion detail) Xindi Insectoids Suliban Shroomies - for lack of a better name
That's one of the downsides to a prequel show if you use too many new Alien races the question becomes why haven't we heard of them before and using often seen Alien races in the previous shows is also a downside because then it becomes why aren't we seeing new races, we're just never happy. But really the only new Alien races that stick out as even remotely memorable are the Xindi and Suliban.
Actually I thought the new aliens in the "Silent Enemy" episode were really cool and well-executed onscreen. (Edited my list above.) Rather then popping on the view screen and demanding the Enterprise to leave their system like so many other encounters throughout the different series, they presented more of a mystery and a building menace that was really well done. (Referred to has "Shroomies", they received the name "Elachi" in Star Trek Online.)
my head canon. without the support of the "time lords" the suliban cabal collapsed after several years and the suliban people require over a century to pick up the pieces. they began to focus inward. the xindi descend into civil war, by the 24th century they're all but gone. their combined population is below one million.
I like that. I shall assimilate it and add its biological and technological distinctiveness to my own canon.
Edited, since the Xindi seem scarce lately. Klingons and Ferengi some Vulcan are most helpful so have to adjust the original having thought of there.
Xindi Insectoids Xindi Reptillians both because they were menacing bad guys Andorrian Women because they were hot Silent Enemy guys, weird Did I mention Andorrian Women ? Anything but fecking Klingons