Derwoody stated that General Physics should apply to a fanatasy setting. This only half correct. There is nothing wrong with a world that violates our laws of science (evolution, gravity, least effort etc) as long as it is self-consistant. That is: one law should not apply to only one creature, object etc. All laws in the world should be universal.
Secondly, the argument of \"there is magic\" is not acceptable when describing science. Just because magic exists, does not give anyone the ability to dismiss criticisms of science. Magic in itself must be bound by laws, and therefore the \"it is a magic object\" excuse doesn\'t give a person free reign over \"creativity\".
Thirdly, just because Klyos have wings doesn\'t mean they can fly like a bird, they may glide. Indeed many large birds are too large to \"fly\", rather use updrafts to achieve altitude.
Fourthy, the size of an animal has less impact than many people think. Quetzalcoatlus is certainly larger than Klyos. What is important is the wingspan-weight ratio. Also, there is nothing preventing Klyos to have a bone sturtcure that is superiour to ours.
Lastly a few minor points:
1. Lizards do not have slimy skin. Exposure to water makes it \"wet\". The slimy texture would originate from exposure to mud (which maybe their habitat).
2. Amphibians generally cannot breathe underwater (but their larvae can). Klyos can.