Hombre,
Your's is a Creole knife, known locally as a `puņal' on account of its small false edge, and it is the most common type in use since the demise of the legendary large `facon' of the 19th cntry and earlier.
`Puņal' is a misnomer that equates with `poniard', a primarily stabbing weapon and a typology that this blade shape does not fit, being that of a working knife intended for cutting tasks. As to why the locals decided upon this name for these knives is not known.
The brand is that of `La Movediza' a factory that started cutlery production during WWII and finally closed its doors in 1963. However blades with this brand keep turning up and there is much conjecture in Argentinean circles as to whether these are unsold originals or later fakes trying to cash in on this iconic brand.
Because of material shortages during the war, the knives were made from recycled steel taken from scrap and their quality is said to be highly variable.
You may find these two threads of interest:
http://www.vikingsword.com/vb/showth...light=movediza
http://www.vikingsword.com/vb/showth...light=movediza
Cheers
Chris