Thanks to all that helped me with the ID of the plant, you are absolutely right, its not an aroid but belongs to the piperaceae family.
At the beginning i thougt it was some sort of scindapsus, but then i realized that it lacks some typical characteristics of that genus, specially the total absence of roots traces at the nodes, and i also made a google search and found nothing like that plant under scindapsus and related genera.
Then the plant flowered to me and the flower reminded me of an aroid spadix, but the spathe was missing, so i thought it could be totally reduced or someting like that...
I grow peperomia, but never related the inflorescences of each other, as peperomia are so compact and look different!...
That flower, the leaf attachement, the growing habbit and the shape of the leaves of that piper fooled me all this time! But now i am glad that i finally know what it is!
Anyway, I apologise to ask this here, since this is an aroid list and not piper list, but can we tell that the inflorescence of aroids (monocots) and piperaceae (dicots), that are so "far away" from each other, be considered as some sort of convergent evolution? At first glance they really look very similar, even in the floral arrangement. I would like to know your opinion!