Frederico, I love both I and II. Don't mean to sound brain dead but are these a name change from Lycaste or is Lycaste in the same Family????? They look so similar.
Bifrenaria and Lycaste are different Genera, but closely allied; both are in the same Subtribe (Maxillariinae) in the Tribe Maxillarieae, jointly with genus Maxillaria, Anguloa, Scuticaria and Xylobium, among others.
In terms of Genetics, Bifrenaria are closer to Rudolfiella and Scuticaria, and Lycaste is closer to Anguloa and Neomoorea. But looking the flowers, you are right, Bifrenaria and Lycaste are very similar!