This is a good question. As a wise scholar once said, it is likely that, in the Qur'an, Allah focuses on angels and jinn as the main sentient creatures other than humans since they are the ones we are most likely to have some sort of interaction with. However, this does not preclude the possibility (or, indeed, likelihood) of the creation of other beings.
It is narrated from Imam al-Baqir (A): ‘Perhaps you think that Allah has only created this single world, and you think that Allah has not created anyone other than yourselves! Nay by Allah, Allah has created a million worlds and a million Adams and you are in the latest of these worlds and of the latest Adams.' - Tawhid al-Saduq
There is a hadith from one of the Imams saying that Allah has a planet with a different length of day from Earth on which the inhabitants do not know that Allah is disobeyed anywhere. (I do not have the reference offhand, but perhaps someone can add it.)