While there are many different species of aliens in existence, we have 7 main (intelligent) types of alien beings. According to Riley Martin, these 7 intelligent alien races sit on a "high council" and reside together on a mother ship near Saturn.
From
http://en.wikipedia.org/wiki/Riley_MartinMartin describes seven types of extraterrestrial beings who reside in a mother ship near Saturn:
the Biaviians, the aliens who have had the most interaction with Martin, who are short with large heads,
the Targzissians, who are "obviously" Reptilians,
the Stagyians, who have a bony, leathery appearance and a peaceful and scientific disposition,
the Dorians, who resemble blonde-haired, blue-eyed humans (see Nordic aliens),
the Insectillians (a.k.a. the Skreed), who are "smart bugs" five feet tall,
the Nyptonians, who are "water people" with "underwater bases" on Earth.[4]
A seventh type of alien that cannot be pronounced by humans.
These seven types are the intelligent extraterrestrial beings allowed to sit on a "high council". There are other extraterrestrial beings whose species are not represented on the council.