Bhuurpedia
1. Anatomy.Imagine a tyranosaurus, but much smaller. Paint it white. Remove the eyes. It won't obviously need so muscular legs, so you may slim them down somewhat. Arms and tail should be longer. Somewhat enlarge the cranium and rebuild its mouth flatter and wider. Add bat-like, scaly ears. Its teeth should be removed and replaced with some dull ones. And let it close its goddamn mouth, so it won't look like it constantly smiled.
Well, this something would resemble a Bhuur gatherer.
They are equipped to move through the caverns. Clawed paws let them climb through mountainous areas. Their limbs have not yet specialized, but they already have begun to. As for now, gatherers walk on their two often, using front limbs to carry the food.
As there isn't much food underground, they needed to develop effective means of digestion. Their stomach acid, through based on HCl, is much stronger than other animals' and full of digesting enzymes. It can digest not only unprotected tissue (which does not actively try to neutralize the acid), but also bone, wood and some hydrocarbons. Most of them are further reduced in intestines almost to their core components (if it's needed). New proteins are synthetised from reserves stored in various organs - derivatives of the liver. But most substances are converted to glucose.
It does have some disadvantages, as Bhuur regeneration rate is somewhat slow. One of them needs much rest to heal a major injury, which means being useless. Most of lizards just devour their wounded.
Perhaps that's why they seem to rage when severely injured. They are screwed and their organisms know, so they make use of their stored energy fast. Sudden bursts of strength from a seemingly debilitated Bhuur are not uncommon.
Their mouth is adapted to eating just everything. Teeth can grind both plants and meat. If for some reasons it's not enough, vomiting on the food usually makes it edible. As Bhuur esophagus and mouth are protected from the stomach acid, it doesn't hurt them.
This species has no eyes. Their remnants are closed inside the skull and completely useless. They use echolocation to orient themselves and smell to localize their prey. The former is also one of their means of communication (the second one is burping).
Skin barely protect them from anything save cold and their acid. Particularly it offers almost no UV radiation resistance. The light of the sun causes sunburns and sometimes cancer. Even the light reflected by the moon can be harmful if exposure is long enough. They are much more resistant to alpha, beta and gamma radiation.