start stage end stage artery primitive mesencephalic artery PMsA TAO:0001062 zebrafish_anatomy ZFA:0001062 Artery that branches dorsally from the cranial division of the internal carotid artery, then curves caudally along the dorsal medial wall of the eye capsule to drain into the PMBC just rostral to the midbrain hindbrain boundary. pharyngula:prim-5 pharyngula:high-pec