Well you can learn something new every day. I found this discription of Oysters on the Texas Parks and Wildlife Agency
Eastern Oyster (Crassostrea virginica) . It certainly is an impressive way to describe fresh oysters! I have shucked a few oysters in my years and never have I had the good fortune to experience this:
“Frequently, the novice oyster shucker will encounter a golden-brown “worm” within the oyster’s body. The initial reaction is to throw the oyster away, thinking it is parasitized. However, the “worm” is an enzyme complex formed by the oyster itself when it has been actively feeding. Thus, it could be considered a mark of freshness. Red and green worms that live outside the oyster’s shell sometimes wander across the shucked oyster meat. They may be startling, but should not interfere with the enjoyment of the meal.”
Enjoy! 