Encysted eastern elliptio mussel larvae (glochidia) on its American ee

A close-up photograph of an American eel’s (Anguilla rostrata) gill with larval mussels (glochidia) attached.  Larvae will remain on the gills for 2-4 weeks until they metamorphosis into juvenile mussels.  Juveniles detach from the host gills and settle into the river’s sediment where they grow into adult mussels and can live as long as 100+ years.