part of start stage end stage neural arch neural spine Neural spines are extensions of neural arches dorsal to the neural canal in the median skeletogenous septum. Neural spines are typically unpaired median structures but can be paired in some instances, e.g., in the abdominal region of basal teleosts such as Leptolepis, Elops, Megalops, and Hiodon). neural spines zebrafish_anatomy ZFA:0001336 TAO:0001336 endochondral bone unknown adult