The requested vessel with name SEIYU MARU and MMSI:0 and IMO:5319042 is temporary not in our database.
Perhaps you mean one of the following ships:

Vessel name IMO MMSI In range Destination Last report
SEIYU MARU 9682174 431004475 >JP KZU OFF Feb 20, 2018 21:46 UTC
SEIYU MARU N/A 431002433 > JP HIM Feb 20, 2018 21:07 UTC

Also, you may try to find the vessel in our comprehensive Vessels Database or track this ship on the map.