Unidentified gastropods from Queensland

[khan]

Hello Pierre,
This is some ways to follow, from left to right :
1 : hard to say, but can be a beached juvenile of Cerithium coralium
2 : Potamididae family, must be Cerithideopsilla cingulata
3 : no idea...
4 : genus Polinices, this looks like a beached Polinices bicolor, but the range of this species is near Taiwan.
5 : must be a juvenile of Telescopium telescopium

These species are typical from muddy sand substrates. Maybe this can help.
J'espère que cela vous donnera quelques pistes.