Ah, yeah, I'm pretty sure that lever could worry itself off on an ME Super, (Haven't actually had mine apart, but this does happen occasionally.) If it were a sharper image, I could be sure, but that'd appear to be the case: in order to prevent losing the lever, you probably want a replacement part, good news is they're common. I suspect a couple little dots of cement might hold it on in the meantime, but why don't you wait for another opinion.
(These reverse-threaded, I presume, guys? I could probably just look at mine, later.
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