probably a whole race of ‘em
https://www.google.com/search?q=district+9&source=lnms&tbm=isch&sa=X&ved=0ahUKEwinxeSWvrLaAhUH0FMKHQ1VCh8Q_AUICygC&biw=1920&bih=988#imgrc=xLyEqjLva2UYnM:&spf=1523458852786
Prawns you know