The true identity of the largest fossil flower preserved in amber

The largest fossil flower preserved in amber has been correctly identified: with a corolla diameter of almost three centimeters, it bloomed over 34 million years ago in the Baltic region on a small plant currently extinct belonging to the Symplocaceae family (nowadays widespread in Southeast Asia) and not to the Theaceae family as hypothesized for over a century.

It has been demonstrated by the analysis of the pollen grains encased in the amber carried out by Eva-Maria Sadowski of the Natural History Museum in Berlin and Christa-Charlotte Hofmann of the University of Vienna. The findings, published in the journal Scientific Reports, will help to understand which plants formed the ancient Baltic forests during the late Eocene, a period when the climate in Europe was hot and rainy.

The fossil flower, from the largest amber deposit in the world (Kaliningrad), has five petals and is three times larger than any other amber-encased fossil flowers known so far. The specimen was first described in 1872 as belonging to the species Stewartia kowalewskii (of the Theaceae family) and dated to the late Eocene (38-34 million years ago).

After 150 years the two researchers decided to re-examine it, creating new detailed images and studying the pollen, laboriously extracted with a scalpel and analyzed under a scanning electron microscope.

The results show that for over a century the flower has been attributed to the wrong species: it is instead closely related to the Asian plant genus Symplocos and for this reason the two experts proposed to rename it as Symplocos kowalewskii.
This is the first fossil evidence of such a plant genus preserved in Baltic amber, but the ancient forests of the region were home to many plant species whose modern descendants are found today only in East and Southeast Asia. Together they formed a varied ecosystem, consisting of swamps and mixed forests.