astomatous

This feels like a bit of a sci-fi word, though I suppose it's more about nature than robots:

astomatous adj mouthless, or without a mouthlike opening. Also astomous. [Origin from Greek a- (primitive), and stoma, -atos mouth] Chambers, 1998

So, R2D2 would be astomatous, although I wonder if that black slit on his body is meant to represent a mouth somehow? This word is probably more useful in biology, talking about very small organisms. I would like to make it a bit broader in meaning though. Something like, "Would the royal family be better liked if Prince Philip was astomatous?" for example.