I am pretty sure this is not bimaculoides but wonder about bimaculus. O. bimaculoides shows definite orange around the suckers where these show the more typical blue/purple of O. hummelincki. I have not seen definitive photos of O. maya but both are on the other side of the canal. The eye spot on the bottom one does not show the yellow/orange center and is not completely round but I have seen in O. hummelincki but I have seen the eyespot show differently or not at all. Are there any definitive photos of O. bimaculatus to examine? I know they are not supposed to be visually distinguishable but the open part of the eye spot brings to mind some of the descriptions and I have not seen other references to the sucker tips to know if they may be different but not often reported.
O. hummelincki from the Caribbean (I have seen enough differences to wonder about at least 2 different animals here) can show those yellow "pimples" around the eyespot in a similar pattern around the eyespot (last picture).
They can also show that craggy look (as can O. bimaculoides):
However, given the location, the eyespot, and sharpenss of patterns, I would look for a match on O. bimaculatus if the rings around the suckers can be blue vs orange.
I did a little research and came up with a suggestion for the first two as well. I believe they are O. oculifer. Orginially not found along the coast of Panama, however, I did find a source that said their range has extended to that area... (once again, if someone would like to confirm, that would be awesome).
Hhhmm, yes, it is an ocellate, however all the pictures I've seen of it (not many thanks to google images) do not appear to have a promanent ocellus. The blurb I read said that the ocellus resembles a dark patch of pigment... which unfortunately is a ridiculously vague description. Oh well, it was worth a guess! haha.