Rhea.
It does not have a known name apart from 'trident'.
the function of Poseidons temple was for Poseidons honor.
Poseidon's sign is a trident. Other signs include horses and an earthquake.
Rhea.
cronus
Cronus and Rhea
Triton
a trident
He doesn't had friends
In myths, he does not have one.
The sea, particularly the Mediterranean.