Double Bass Ribs shrinking?

[Arduy]

Hello everybody. Today I took the endpin out of my double bass to reduce it's lenght, and I noticed at the bottom of the instrument where the ribs meet (and where the endpin is) that the entire joint has come apart for about 1,5 mm (I'm sure there was no such separation there before). There's no other problem with the bass. Could it be wood shrinkage? What can be done? Any help would be much appreciated. Thanks.

 

[arnoldschnitzer]

Look inside and make sure the tailblock is not split in half.

 

[Arduy]

From what I can see the tailblock isn't broken, but it's hard to tell (the wood grains are quite evident and follow the direction of the presumed rib separation, the visible glue of the tailblock is continuous). There aren't any seams open around the bass.

 

[toman]

So the ribs are still attached to the block, but there's a gap where they meet? I'm not quite getting this.

 

[Arduy]

Yes, there is a gap that wasn't there until now. The endpin block inside the db doesn't seem to be broken apart. I'm a bit worried, but in two days the gap hasn't extended; so I'll wait to see if it stabilizes. I know I should go to a luthier, but this would be difficult for me at this moment. If the endpin block breaks I imagine that the top of the instrument should be removed in order to do repairs...do not tell me that!...
Maybe a few pictures may help:

Thanks for the help.