Oophila

Oophila amblystomatis, commonly known as chlamydomonad algae or salamander algae, is a species of single-celled green algae. The Latin specific name 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 as a result of photosynthesis. This is an example of symbiosis, and the only known example an intracellular endosymbiont microbe in vertebrates. This symbiosis between Oophila and the salamander may exist beyond the oocyte and early embryonic stage. Chlorophyll autofluorescence observation and ribosomal DNA analysis suggest that this algal species has invaded embryonic salamander tissues and cells during development and may even be transmitted to the next generation.