Christian identified the connector on the extension cerd as TX25-40P-LT-H1E.
I was looking for the other part (I would like to build a “riser” card in between the X32 and the extension cards to make the debugging more comfortable and not to have to solder wires onto the card(s) ): I found that 40P means 40 = 40pins / P = PLUG.
So I searched for the opposite which I though would be RECEPTACLE, i.e. 40R. But a TX25-40R-LT-H1E doesn’t seem to exists, but a TX24-40R-LT-H1E which can e.g. be found in the mouser eshop.
Can you please confirm that this is the correct countrerpart to theTX25-40P-LT-H1E ?