RESULTS
Skin tissues from all 27 species contained both carotenoid and pteridine pigments (Figure 1). Among our samples, lutein/zeaxanthin (yellow) and β-carotene (orange) were the carotenoids with the highest concentrations. Isoxanthopterin and pterin-6-carboxilic acid were the pteridines with the highest concentrations but we also found substantial concentrations of yellow xanthopterin and red drosopterin (Figure S1).