part_of part of part of existence starts during or after Stage 6 trail cell PMID:30485821 Ovo+ neoblasts and post-mitotic eye progenitors that simultaneously migrate and differentiate into photoreceptor neurons and non-neuronal pigment cup cells comprising the optic cup. PMID:23250205 Planarian_Anatomy PMID:24040508 eye progenitor cell ovo+ eye progenitor PMID:21852957 eye progenitor PMID:29674431 https://orcid.org/0000-0003-2569-1939 | https://orcid.org/0000-0002-7535-4940 PMID:27606067 PMID:28072387 PMID:28245923 PMID:22884275 visual system neoblast