Ah... my bad (I've misread your post). Then again I didn't make it slimy, it was "just" out of water so it is kind of glossy (that was my intention, I'm sorry that you didn't see it that way...) just to indicate to the viewers that they are at least semi-aquatic and amphibian-like. You have reading into too much of my drawing, it wasn't suppose to be representing sliminess of the skin...
To be honest, I do doubt that they have a full coat of reptilian scales, the best that they would have developed are fish-like dermal scales (which are not homologous structures to the reptilian scales).
When you said "well known" (...that these animals had a covering of scales...) from your original message I thought you must have some kind of direct evidence to back your claim, however, on your last post you stated that you are basing this from a picture and your interpretation of this picture. Sorry from my ignorance and I'm sorry but only a picture (from your last post) doesn't make it a "well known" fact. It is just a theory.
This actually reminds me of the "biplane microraptor", I won't get into the details but basically you have one group of scientists saying that they (microraptors) sprayed their legs because it is more flight efficient and "logical", on the other hand you have another group of scientists saying that it would be structurally (hip socket and femur head joint) impossible for the microraptors to achieve such pose. I've seen some of the leg spraying illustrations of microraptor... so does it make it a irrefutable "well known" fact that they sprayed their legs during flight (because it is logical) or even have the ability to spread their legs to the side? It is a theory... yes but has it been proven as well known (proven fact), the answer is NO...
BTW when I said leathery skin, I was talking about perhaps something equivalent to some tree frog skin which has a waterproof layer (perhaps developed from keratin, similar to the keratin that you found on their hands and feet).