In some really rare cases
Marina can be called by
Maria's nickname -
Masha.
Marina is my mother's name and she is a Russian jew from Petersburg. She gets called Marisha, Marishka, Marishen'ka, Marinochka or Marinka. (She gets called
Marina in situations she doesn't know interlocutor very well and she doesn't want to be called too oficially -
Marina Aleksandrovna)
At the moment
Marina is not the trendiest name in Russia, but many of about 50 (or 30) years old women are named
Marina.
...................
'Not causing trouble, not touching anything, fixing the primus'
Bulgakov, The Master and
Margarita