We decided to focus on the weird and unusual with our latest AquaNerd Picture of the Week. Our subject is the thorny oyster (Spondyllus sp.), and as you can probably tell, that name is very fitting to some extent. Where the name is wrong is the oyster part. The thorny oyster is actually a clam, but it doesn’t use photosynthesis like the far more popular Tridacnid clams. Instead, it is a filter feeder that requires heaving feedings of plankton based products. Additionally, the thorny oyster can be quite difficult to care for, making it a not so common find in the aquarium trade.