I like looking at Utric flower pics so I enjoy looking in this thread (even if it is old...). Here's another species not represented: U. campbelliana
.... or a bit closer:
I did some pollinating on 04.26.14 & 05.04.14. Sorry - I don't remember when they started to open. I planted seeds on 06.25.14. The only real seasonal clues mine get are temps - basement lighting doesn't move.do you remember what time of year they bloomed for you? I am guessing they are seasonal. Now that mine has filled out some wondering if it will bloom...