Most lions will eat anything that can fit into their mouths. They have pretty big mouths to. I'm not sure about the fumanchu ," or any lions for that matter", when it come to your inverts. Some of them will completely ignore your inverts and some of them will eat them like candy. It is IMO,"please correct me if I'm wrong", impossible to say for sure though until it's too late. About the only things that can be kept with the assurance that your lion won't eat them are critters of at least 1/2 of the lion's body length. I don't know of any genera of lions that aren't like this but, someone else may.
hth
Chris