Hard to tell from the picture but typically what they’ll do is leave behind little pieces of them selves as they move around the tank and those little chunks grow into full sized Yuma’s.
Difficult to make out, but it sounds like it. Mine looked like little patches of the flesh near the edge of the Yuma first, like it was stretching out a root almost, but flat. Then they got more color, and began to fluoresce under the actinics. Finally developed into little mini yuma. These are how mine look right now.