In the Surrey woodland of southern UK mainland I chanced upon a piece of corrugated metal. Lifting it up I found a bare patch of soil except for what appeared to be a nest of dry plant material and two palmate newts.
The newts had suffered traumatic removal of most of their heads leaving just the back-most portion of the skull and a dry wound with an airway/oesophagus present, little or no sign of a lower jaw or orbital sockets was present.
The newts showed rudimentary reflex withdrawal from gentle prodding, confirming that basic life-functions continued.
This was a rodent's nest and larder (food-store), the newts being preserved (and immobilised) in this way for later consumption.
Assuming sufficient body-mass and internal resources to draw from (and not being interrupted by being eaten), might these newts be able to regenerate to become fully functional again? (The question of resource limits within a newt might be mooted, but not the primary focus of my question).
perfect adult regeneration of many other important tissues and structures as diverse as heart, brain, spinal cord, jaws, retina and lens, has also been described
Experiments have been done on newts, in which a 70% of the optic tectum is surgically removed. A proliferative response was observed in these animals and after 8 months the tectum was almost fully regenerated, but the origin of the new neurons was not investigated (Okamoto et al., 2007).
Here, it's later indicated that the origin of the progenitor cells for the regeneration is not known.
I'm unable to find or access any more recent or advanced research