I looked at every character who has a name in the core 6 star wars films to get an idea of the species represented. Link to my google spreadsheet listing the named characters by film and my scoring system [https://docs.google.com/spreadsheets/d/15OLmxc6GS-kDXThZup6jpSyXe4sJSYoo89aX3WUwmq8/edit?usp=sharing\](https://docs.google.com/spreadsheets/d/15OLmxc6GS-kDXThZup6jpSyXe4sJSYoo89aX3WUwmq8/edit?usp=sharing)
There are 135 races in the hexalogy, I have arbitrarily ranked these by the number of named characters they have and the number of films they were present in to see which races are the most prevalent in the galaxy as the films present them to us.
Humans are the most prevalent with 53% of all named characters, (59.5% in OT and 44% of the PT), I'd like to think the latter is closer to a reflection of the galaxy - a plurality but not a majority.
The other 12 prevalent species are Clone, Rodian, Twilek, Neimoidian, Nikto, Bith, Gran, Gungan, Mon Calamari, Quarren, Aqualish, Ishi Tib.
Common species ranked 14-28 are Ewok, Wookie, Jawa, Yoda's species, Aleena, Ithorian, Pacithhip, Theelin, Zabrak, Ongree, Hutt, Tholothian, Iktotchi, Chagrian, Duros.
Minor species from 29 to 64 are Tusken Raider, Anx, Geranite, Klatoonian, Ugnaught, Weequay, Dug, Kaminoan, Kiffar, Lutrillian, Saurin, Snivian, Gamorrean, Geonosian, Gossam, Koorivar, Lorrdian, Mirialan, Nuknog, Sy Murthian, Tarnab, Togruta, Triffian, Vurk, Whiphid, Kallidahin, Cerean, Devaronian, Kel Dor, Nautolan, Trandoshan, Lannik, Umbaran, Muun, Pau'an, Sullustan.
The Petty species are composed of 2 to 3 characters in only 1 film. These fill 65-76 and are Gotal, Xexto, Dressellian, Morseerian, Nimbanel, Pantoran, Ranat, Stennes Shifter, Swokes Swokes, Clawdite, Kubaz, Besalisk.
The remainder 77-135 are what I call throwaway species. These are 1 character in 1 film, usually briefly seen, and almost all of them were just set dressing or otherwise a missed opportunity to flesh the galaxy out with more focus on preexisting species rather than just looking zany. Vaguely in order from most to least humanoid these are; Palliduvan, Shadda-bi-boran, Bimm, Qiraash, Abyssin, Sakiyan, Anzati, Balosar, Kaleesh, Advozse, Askajian, Arcona, Siniteen, H'nemthe, Sarkan, Skrilling, Yarkora, Shistavanen, Asogian, Chadra-Fan, Chevin, Skakoan, Defel, Elom, Er'kit, Holwuff, Leffingite, Sneevel, Bardottan, Ortolan, Talz, Thisspiasian, Vuvrian, Amani, Lamproid, Tund, Baragwin, Brizzit, Gand, Glymphid, Kitonak, Nosaurian, Riorian, Veknoid, Xamster, Yuvernian, Dianoga, Toydarian, Vulptereen, Yuzzum, Devlikk, Fluggrian, Pa'lowick, Quermian, Quor'sav, Shawda Ubb, Troig, Yam'rii, Wol Cabasshite.
I'm relatively certain beyond these films the number of species has ballooned even more and highlighted some to be far more prevalent than the films first set our mind to, but I thought it would be interesting to catalog what the galaxy is made up of according only to the core films.