Flowers just seem so complicated to me so I'm sure it is something obvious. It opens up fully around noon but closes for the night.
Very likely some species tulip. Have a look at the foliage and compare with Tulipa kaufmanniana or T greigii,
Does it flower before big fat garden tulips in your area?
K.S.Veitch - I'm sure you must have plants in your blood if you dig deep! Maybe an ancestor?
Here is a link that might be useful: Veitch Nurseries