sandtiger;484086; said:
Not all mussels have a stage like this, zebra mussels are not parasitic.
I would not keep them in a tank though. I actaully had some once, not with fish but with newts. They came in on some wild plants I collected and quickly took over the entire tank, worse than snails. If you want something similer try freshwater clams, I collect these quite often and also live in NY, they are about the size of a thumbnail.
Yep, you got me there. Their life cycle is:
* Preshell Larva - the shell has not formed yet.
* Veliger Stage - the velum develops. Velum is the organelle used for feeding and swimming.
* Straight-hinged Larva - the first time the shell is all around the internal organs.
* Ilmbonal Larva - the shell is not transparent anymore. (The umbo is opaque.)
* Post-Veliaer Stage - time after the velum has finished developing.
* Pediveliger - has foot to help it move. The shell is thicker and whiter.
* Planti grade - the last stage as a larva. The shell is not round; it has elongated. The siphons form. Siphons are holes for excretion and respiration.
* Settling Stage - the zebra mussel has finished making organs, gills, and siphons. It is now a juvenile and will be an adult when it can reproduce. It has also made byssal threads to attach itself to things.