Orchid and bees

I was not only surprised at the number of bees visiting this Catasetum orchid, but also by the kind of bee. This one is different than the big black bee (mangangá) on which I reported a few days ago. I would assume that these bees are also classified as orchid bees, but I'm not sure. I never saw more than two mangangá bees at a time. As you can see from the image, there are at least half a dozen here.