Using PeIm to remove a magus's touch species, can they still cast touch-range spells?
I think the question is too broad to be answered, even though it doesn't seem broad. For instance, R: Touch is used to affect your own magic while not implying you can feel a spell itself by touch. Also, R: Voice doesn't require the target to have ears to hear you, rather you sense your target by sight or whatever. So, in general, it wouldn't matter. But if the magus were also blind and as a result were relying on the sense of touch to sense a target, then there would be problems in my opinion.
It's not a question of detection for the casting magus. If they are invisible, Eye-range cannot work. If the casting magus emits no sound species, they are silent and thus voice-range spells don't work. Do touch-range spells work on the similar basis, were the magus to remove their touch species?
Oh, I thought you were stopping removing all touch species the magus would receive. It doesn't really matter for my answer, though. Think of the Vim spells. You don't actually touch them, so R: Touch doesn't necessarily mean touching via touch species. R: Sight spells can be cast while invisible, why not R: Touch when you can't be felt?
You can cast R:Touch spells by touching the target with your talisman.
You do not receive tactile species from an object you touch with your talisman.
Ergo, R:Touch does not require interaction of tactile species.
Isn't it the other way around?
If you remove the touch species from the target you can't cast it?
interesting question by the way 
Widewitt