I think you could definitely rule out all others except tigrinum and magdaleniatum. Would need to do more in depth research but from just the patterns on the ones I have seen this looks like your two possibilities to me. Not to say that I am right. 
this is just my opinion. A quick observation just from what I remember in the differences in the patterns and reviewing the updated Pseudoplatystoma info from a few years back. Favors tigrinum more in my eyes though. Again could be wrong. Hope this helps narrow it down some lol.
this is just my opinion. A quick observation just from what I remember in the differences in the patterns and reviewing the updated Pseudoplatystoma info from a few years back. Favors tigrinum more in my eyes though. Again could be wrong. Hope this helps narrow it down some lol.