Ooooh Lin, i'll not be growing this plant and already it is on the compost pile because i have limited garden space and all my plants are either nectar rich for the bflies and hummers and bees and/or host plants for the bflies and most of the Ipomoeas are not sufficiently interesting in this regard. As for adding the photo of the seedling, i am not certain that it is in fact I. lobata. There could be several Ipomoeas that may look like this photo that are not lobatas. I didn't research that thoroughly because if it's I. lobata or something similar, i am not interested in growing it. Also, i am very careful about images i add to the database. I won't add anything that i am not 99% (i always like to leave room for possible error) certain of. As far as i am concerned, the thread isn't so much "solved" as it is "finished" in that i have enough information to serve my purpose. I don't know how the thread could be solved unless i grew the plant to see what it actually is and i don't have enough space to do that.
On the bright side, i am growing another volunteer that showed up in my garden. It is a Lupin and i am hoping it will be a native and that i will be able to identify the species so i can add it to the database. I am really excited about this one.