TY, Becky!!
Lin, something between the time of your comment and when I looked a few minutes ago, but none of the entries on P. grandiflora look like P. pilosa to me. P. pilosa has only 5 petals, flowers are about the size of a pencil eraser, always hot pink, not sold at stores (except maybe a specialty succulent place.) P. grandiflora flowers are so much bigger. P. oleracea flowers ARE always small and yellow, also with 5 petals.
You don't sound confused to me, you noticed the same discrepancies I did. Taking common names out of the discussion clears up everything. Not much point in discussing which is more often called purslane, or moss rose. And how would one say "chisme" anyway? Chiss-me? Kiss-me? Chizme? Chiss-um? Cheese-may? IDK, and don't want to devote memory space to that.