I thought that the oncidium alliance plants all had either one or two leaves at the apex of the pseudobulb. Apparently, I was wrong, because the newest pseudobulb on my Miltassia Shelob has three. Any ideas what's going on here????
It is most likely an accident... I have had an Oncidium Gower Ramsey 'Puna Queen' develop 3-5 leaves on the apex of a bulb... it also produced some new growths without bulbs that looked like a reed-stem Epidendrum (it eventually killed itself)...
I am unsure what causes it, perhaps growing conditions or just wanted to grab your attention... =)
Trifoliate pseudobulbs are not seldom among the Onc-Odont-Allies, e.g. Onc. flexuosum, Onc. ornithorhynchum are heavily used for hybridization. And don´t forget how some clones where tortured with colchicine and so one. As long as it blooms, don´t worry!
I have a Shelob Tolkeine that also does this from time to time. I have noticed that on these growths the blooms always are of supeior size and substance. As well as double spikes. I think its just in the genes. Nothing to really worry about!