`SQLite does not exist` despite Mono.Data.Sqlite added as reference in Xamarin on OS X

In Xamarin Studio on Mac OS X 10.10.2 I wrote a C# class that uses SQLiteConnection.

Xamarin complained about not knowing the class so I added using System.Data.SQLite;

Then when compiling Xamarin said:

The type or namespace name `SQLite' does not exist in the namespace `System.Data'.  
Are you missing an assembly reference? (CS0234) (CmisSyncContextMenu)

So I opened Edit References and added the Mono.Data.Sqlite:

I clicked OK, pressed Rebuild all and... I get the exact same error message as above.
What am I doing wrong?