The stapedial artery is an embryological vessel arising from the primitive second aortic arch that divides into a dorsal branch (the future middle meningeal artery) and a ventral division (future maxillary and mandibular arteries).  These divisions link with branches developing from the external carotid artery during the third fetal month causing the stapedial artery to regress.

If the stapedial artery persists in postnatal life, the middle meningeal artery arises from it thus the foramen spinosum (normally containing the middle meningeal) is absent.

The vessel is important to recognize as it can be confused on examination with vascular tumors such as tympanic paraganglioma.  It should not be biopsied as it will bleed profusely.