text: 5ubi:loxP-GFP-loxP-mCherry) (Mosimann et al., 2011; Kaufman et al., 2016) larvae/ metamorphic juveniles, even when nearby neural crest-derived cells in branchial arch cartilages and/ or gill filament mesenchyme were mCherry-positive (Figure 1g-h’; 166 serotonergic cells located near such mCherry-positive cells [ 6 per fish] were counted across 10 larvae/metamorphic juveniles).