Hi Olivier,

The first bivalve looks like a Tellidora (family Tellinidae) . I'd have to
look it up to tell which species.
The abalone - perhaps Haliotis varia - again my best guess without reference
materials handy (I'm at work)
The first tree oyster - probably an Isognomon, species uncertain
The second one - probably Malleus albus
The last bivalve - I believe it is Hecuba scortum, family Donacidae.

Regards,
Paul M.