part of start stage end stage portion of tissue optic choroid tapetum lucidum zebrafish_anatomy tapetum cellulosum 2019-05-29T16:15:09Z ZFA:0005916 Ceri Iridophore layer that forms along the dorsal region of the poster segment of the eye. The tapetum is formed by a single layer of Iridophores and is proximal to the photoreceptors and is located in the choroid. The tapetum reflects photons back to the photoreceptors if they were not initially absorbed by the photoreceptors. unknown adult