title_body: Which sounds could a lipless humanoid produce? In my world, I have a race of humanoids who speak a language called Gé̃kt, which is derived from various Eastern Iranian languages such as Khotanese, Ossetian, Yaghnobi and Bactrian with a dash of Persian (a Western Iranian language) thrown in for good measure. However, these humanoids lack lips and I have no idea how this traits would affect their speech. 
  
  For reference, here are Gé̃kt's constants and vowels. 
  
  
  Consonants: pʰ p p' b f v m w tʰ t t'd tsʰ ts dz s z n r rr l ṭʰ ṭ ḍ ṭsʰ ṣ ẓ ṇ ṛ tsʰ tṡ dż ṅ y kʰ k k' g x y ṅ h q qʷ m  t͡s t͡sʼ d͡z t͡ʃ t͡ʃ' d͡ʒ χ χʷ ʁ w j ɫ  
  Vowels: ι [i] ο [u] ε [e] α, ο [ə] ο [o]? α [a] ει, ι [iː] ο [uː] η [eː] ω [oː] α [aː] e æ o u ɨ ɛː ɔː
  
  
  What sounds may they use to communicate?
upvoted_answer: At first sight, it seems that it is impossible for the lipless humanoids to produce any sounds that involve the lips in their production, this concerns the following groups of sounds:
  
  
  bilabial consonants: pʰ p p' b m w
  labiodental consonants: f v
  labialised consonants: qʷ χʷ
  rounded vowels: o u ɔ
  
  
  But: There is a known art, named ventriloquism, where replacement sounds for those sounds that require visible lip movement are used to produce understandable speech. Maybe the lipless humanoids can cope with this and even learn to produce the Gé̃kt's sounds using such techniques.