You will be hard pressed to find a site that will give you a description of all (or even many) Ball Python morphs. Plus, most only have dorsal, or side, shots posted (sometimes, but not always both) without giving any of the belly.
Here is one video for Spark:
https://youtu.be/PkGPK8aEB8o
Specters/Spectors also have that Yellowbelly complex look, to them. Coloration, a head stamp, etc. Although not as much blushing and the belly is not exactly like that of a YB ... nor is it the same as that of a normal.
Keep in mind that there can be some variability with any morph. While some can be described, as having "this or that", there will be others, of the same morph, that do not follow the same exact description.
Either, of these two morphs, can look like normals to the "untrained".
For Sparks, &/or Specters/Spectors, it is best to go to a breeder known to work with these morphs and who have a fair amount of experience with them.
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