This looks similar to a blade that was sold to me as a Panabas:
http://www.vikingsword.com/vb/showthread.php?t=15658
Maybe this sets precedence for this particular form of blade in a Panabas? Of course, the piece I linked to has not been confirmed as a panabas or even Moro in origin. It does seem to be made very similarly to an old pira of mine though.