Final answer:
The tympano-occipital fissure is likely to be in the region between the tympanic portion of the temporal bone and the occipital bone, which involves auditory structures such as the auditory canal.
Step-by-step explanation:
The tympano-occipital fissure lies between structures related to the anatomy of the cranium, specifically within the auditory region. This fissure is not commonly referenced in standard anatomical texts and may be a variant term or precise description used in specialist medical contexts. However, based on the structures provided in the question, it could be inferred that this fissure would relate to the area between the tympanic portion of the temporal bone (surrounding the auditory canal) and the occipital bone (part of the base of the cranium).
The tympanic portion makes up the floor and part of the walls of the external auditory canal, while the occipital bone contributes to the posterior aspect of the cranial fossae. These two structures are pertinent in the discussion of the cranial cavity and skull anatomy, with the former contributing to structures such as the mandibular fossa and the internal acoustic meatus, and the latter playing a role in the formation of the posterior cranial fossa.