Key resources table.

Reagent type (species) or resource	Designation	Source or reference	Identifiers	Additional information
gene (Clytia hemishaerica)	CheOpsin4	this study	GenBank MF435920	sequence retrieved from Clytia trancriptome data
gene (C. hemisphaerica)	CheOpsin7	this study	GenBank MF435921	sequence retrieved from Clytia trancriptome data
gene (C. hemisphaerica)	CheOpsin9	this study	GenBank MF435922	sequence retrieved from Clytia trancriptome data
genetic reagent (C. hemisphaerica)	Opsin9 n1_4	this study		Mosaic F0 polyp colony
antibody	anti-PRPamide	Takeda et al., 2018		Affinity purified Rabbit polyclonal; against synthetic PRPamide
antibody	anti-acetylated alpha-tubulin (rat monoclonal)	Sigma Aldrich	6-11B-1	(1:500)
antibody	anti alpha-tubulin (rat monoclonal)	Thermo Fisher Scientific	YL1/2	(1:1000)
antibody	anti- ɣ-Tubulin	Sigma Aldrich	GTU-88,	(1:200)
antibody	Rhodamine goat anti-rabbit, Cy5 goat anti-mouse-IgG, Cy5 goat anti-rabbit- secondaries	Jackson ImmunoResearch		(1:1000)
other	rhodamine phalloidin	Molecular Probes		(1:250)
other	Hoechst dye 33258	Sigma Aldrich		(1:5000)
guide RNA (sgRNA)	Opsin9 n1	this study		sequence given in Figure 3—source data 1
recombinant DNA reagent	pDR27457 (plasmid)	Addgene	42250
Transcriptome data	Clytia hemisphaerica reference transcriptome	This study	GSE101072_Clytia_tophat_ trinityGG_combined_v2	Combined assembled transcriptome data from multiple samples.
Transcriptome data	Clytia gonad tissue samples	This study	GSM2698879 GEN-BR1 GSM2698880 GEN-BR2 GSM2698881 GEC-BR1 GSM2698882 GEC-BR2 GSM2698883 GrOo-BR1 GSM2698884 GrOo-BR2 GSM2698885 FGOo-BR1 GSM2698886 FGOo-BR2	Illlumina HiSeq 50nt reads for 8 RNA samples (four tissues, two duplicates for each tissue )