I haven't made a definate connection with what causes it, no, but I can say that, I have noticed it mostly in the morning, about the time direct light hits them and burns off the dew. So the plants are wet all night and then when first they are first exposed to direct sun...is when I've noticed it most. That's not at all to say that either one is to blame, or that they aren't! I can't say Ive ever noticed on poly, I see it on my big alocasias, portora, boa, Mac and odora... I have say and studied it, poked and prodded, and made mental images... What I have noticed is these spots appear early, by 1 or 2pm they are gone, the next day they reappear, sometimes in the same exactly spot and pattern, sometimes in entirely different spots, often both... It's been quite the mystery to me for some years now... I'm not at all sure that it's anything wrong with the plant, certainly unattractive, but not obviously detrimental... I'd like to know more, and speculate less about it! Lets see what I can come up with!

Could be a fungus like Vladimir said, could also be an insect egg or just dirt on a bit of fluff. However, I'm more concerned with how dusty the leaves are. I may just be dust or it could be the beginnings of a spider mite infestation. It's a good idea to wash off the leaves from time to time, like maybe every 4-6 weeks. Take them outside and hose them off, or if that's not possible, put them in the shower and shower them off with cool water. Then let them drain well and put them back where they were. It helps prevent spider mites as they're attracted to dusty plants. And your plants love the rinsing off!

Looks like they didn't like your aphid remedy. Aphids just love lupines. I think if you just give them some time they may recover. One of the leaves looks like it may have a slug trail on it. I spray slugs with a half amonia half water mixture to kill them. I winter sow lupines and they seem stronger than what you buy at the nurseries.

Thanks for the replies! Gnappi, I'm glad to hear it's nothing to worry about. This was taken in our "winter" (if you can call it that, mostly warm this year but I suppose with it being our dry season that could've induced winter-like symptoms in the leaves as well), I'll have to remember to check out the tree to see if it's rebudding now. And I don't fertilize or water this tree at all, it's in our backyard in a line of fruit trees, mostly huge mango trees, so it gets natural rainfall and a huge amount of leaf litter from the other trees that breaks down over time. Euricolemos (nice name), I'm not so sure this is anthracnose. From what I understand of the condition, if such were the case it would affect the fruit as well? All our sugar apples from the trees in our yard are always unblemished even if the trees have leaves like this which leads me to believe it's a environmental/conditional response to something rather than an affliction. Also anthracnose is progressive yes? The leaves just keep these burned-looking margins for weeks/months at a time without dying off. Your thoughts? We have a bit of the fungus on mangoes; especially when they bloom, so I'm roughly familiar with it. How far back should I prune the branches/the tree? I don't believe they've been pruned much at all (if ever) so that sounds like a really good idea. And what should I feed it? I have some Sunniland 6-4-6 with most micros that's a granular slow-release, sounds good? Also most of our trees have grass under them, if I spread out the granular will the grass just absorb it before they tree can be fed or should I just use a heavier amount to compensate for the grass taking some? Thanks again for the responses! I look forward to the replies, Dan