TERM: Description of glossary term.
Fish related glossary
guanine
A crystalline purine chetnical compound found in the inner layers of fish skin. There it
produces iridescent blues and greens called "structural" coloration. (Common in bird excrement, hence the word guano.).
Reference
Barlow, George. 2002. "The Cichlid Fishes (Nature's Grand Experiment in Evolution)". Perseus Publishing. 352 - (ffm03927)