Freshwater clams?

Numerous studies on parasitized fish indicate that the attached larvae are of now harm in the low numbers seen in open systems, but can be lethal and detrimental in closed systems.

Clams do not survive well in aquaria. Most have natural life spans of 10-20 years, so 2-3 years in a tank is pretty pathetic. They need very clean water--they do little to clean a tank--and most starve because very few tanks have the required organics in sufficient volume to provide for them. IMO, one of those things that don't belong in a tank.

Mussels and clams are the same thing, just a different name.
 
Tyella, to answer your question.

Clams and mussels have a high point on their shells called an umba or a ‘beak’. On clams it’s more centralized around a rounded shell. The umba on mussels is of off centered and often closer to the ends of the shell.

The majority of FW mussels in N.A. belong to the Unionidae Family which produce parasitic glochidium larvae.

N.A. FW clam species are concentrated in the Families Sphaeriidae and Corbiculidae. These bivalves are hermaphroditic brood breeders. Larvae develop in specialized chambers within the shell and in most cases are later released as miniature adults.

All in all, I agree with Oriongirl, except that Sphaeriids and Corbiculoids only live for a few years.

Also, it’s a good idea to check on State regulations before collecting or transporting FW clams or mussels. Populations are stressed and many species are regulated.


Tom
 
I must note that Corbicula fluminea - the "golden Asian clam" of aquarium trade infamy - occurs as an invasive across a broad swath of North America.
 
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