On the tenth day of Fishmas, my dear love gave to me… a pinecone fish!
Pinecone fish consist of four fish from the family Monocentridae. It is easy to see how they got their name, with their thick, ridged scales. They live in the Indo-Pacific and are the darlings of aquarists (but are notoriously hard to keep alive).
Fun fact: pinecone fish have glowing photophores (bioluminescent organs) on either side of their lower jaws, thought to be used to attract prey. Their color varies with light levels, going from orange during the day to blue-green at night.