Crab Maggots

The life of a crab isn't all good. There is an endemic fruit fly that lays its eggs in the mouth parts of red crabs. The lavae eat their way out and drop into the soil to finish their life cycle. I tried to find out what the fly looks like, but can't find anything on the internet.

The above information is incorrect - my apologies, I misunderstood. The fly is actually a benefitial parasite. It eats decaying food from around the crabs mouth, which provides a cleaning service. The maggots don't eat the crab itself.