Last year I misidentified these as Marsh Marigold. Now I have better resources, and I know that Marsh Marigolds don’t have this many petals. So based on the number of petals (8-12) and the heart-shaped variegated leaves, it’s Lesser Celandine (to distinguish from Celandine, a larger wild poppy). They follow the sun during the day and close in cloudy or cold weather. The name Celandine is derived from the Greek word for swallow (chelidon), because the early flowering time was also when the swallows arrived. (Last year we spotted these March 22… so… 3 weeks later this year.) Buttercup family.
Lesser Celandine (Ranunculus ficaria)