Gorn, Wadi, Dosi, Betazoid, Bynar, Brikar, Hermat, Tzenkethi, Metron, Voth, Hirogen, Kazon, Ocampa, Nasat, Gnalish, Pakwa-Thanh, Trill, Sti'atch, Axanar, Orion, Kobliad, Zakdorn, Benzite, Rhaanderite, Cairn, Grazerite, Trabe, Aaamazerite, Arkenite,
http://memory-alpha.org/en/wiki/Category:Species
The thing that bugs me most when encountering a new species is the preponderance of 'x's, [roughly 18 from the Wiki list] 'z's [30!] and hyphens [17] in alien names. It strikes me as the author going for strange English spellings to create the impression alien-ness, instead of fleshing out the species with physical details and descriptions of habits and culture.