What is the structure that Osmunda japonica petal cells do not have?

The nucleus. Lagerstroemia speciosa is a small deciduous tree or shrub of Lagerstroemia in Lysimachiaceae. Its petals do not contain chloroplasts, so its cell structure has no nucleus. The nucleus is the largest and most important cell structure in eukaryotic cells, the regulatory center of cell inheritance and metabolism, and one of the most remarkable signs that eukaryotic cells are different from prokaryotic cells.