Sorry I took so long to respond. I was in Chicago visiting the Shed Aquarium. (They had some algae outbreaks too, so I don't feel as bad.)
yum,
I believe you are describing an Otocinclus fry. I couldn't tell you which of your species had the fry. The fry I experienced had vertical stripes, and other odd spots which they either grow out of, or they become covered up by another color layer in the adult scales.
These are the best fry pictures I managed to get. They are from the first spawn. Unfortunately, none of them survived to adulthood. They are blown up pretty bad and very pixley, but I think you'll get the idea.


The first one is of one that is at least several hours old, perhaps as much as a day. His size can be determined by the veins on the sword plant. The second is a brand new hatchling. His body size was smaller than the size of a sand grain (not including the tail.)
Again, thank you all for your kind comments.