This is not actually a scallop, but rather a clam. The bright colors make it a perennial favorite.
Here is a close-up of the "eyelashes" found at the top of the shell.
You can clearly see the foot at the top. The flame uses this to crawl around, when it is not just flapping its shell to do the same. You may be able to make out some tiny red threads going straight up from the flame towards the glass. The flame would attach itself to the glass by means of these threads, and hang there.
You can see the internal structure of the clam, including the feathery filters (top) and the siphon (right).