Most interesting. Did you happen to photo the vegetative growth as well? I haven't the slightest what this is but curious what the overall plant looks like.
My best guess is Sigmatostalix macrobulbon.
More info on Sigmatostalix in Costa Rica here.
Thanks Bruce for your ID help. I checked the Sigmatostalix macrobulbon Kraenzl. out with the description in the Manual de Plantas de Costa Rica and to me there is no doubt.