The green coloration seen in this spotted salamander egg mass (Striar VP #3) is from a specific symbiotic alga.
From Wikipedia:
Chlorococcum amblystomatis, synonym Oophila amblystomatis,[1] commonly known as chlamydomonad algae or salamander algae, is a species of single-celled green algae. When placed in the genus Oophila, it was the only species.[2] The Latin specific name amblystomatis means "loves salamander eggs". It does not occur anywhere in nature other than in the eggs of the spotted salamander, Ambystoma maculatum. The alga can invade and grow in the amphibian's egg capsule. Once inside, it metabolizes the carbon dioxide produced by the embryo and provides it with oxygen and sugar as a result of photosynthesis. This is an example of symbiosis,[3] and the only known example of an intracellular endosymbiont microbe in vertebrates.[4][5]
