Earliest flower bud

[Pandora]

A Jurassic flower bud from China

Abstract

Angiosperms may be distinguished from their gymnosperm peers by their
flowers, and thus a flower is a good proxy of fossil angiosperms.
However, flowers and their parts are usually too frail to be preserved
in the fossil record. This makes the origin of angiosperms and their
flowers the foci of controversy in botany. Eliminating such botanical
controversies can only be achieved by studying related plant fossils.
Applying routine scanning electron microscopy, light microscopy and
micro-computed tomography (micro-CT) technologies, we document a
fossil flower bud, Florigerminis jurassica gen. et sp. nov., from the
Jurassic of Inner Mongolia, China. This fossil includes not only a
leafy branch but also physically connected fruit and flower bud. The
developmentally interpolated existence of a blooming flower between
the flower bud and mature fruit in Florigerminis suggests that
angiosperm flowers were present in the Jurassic, in agreement with
recent botanical progress. Florigerminis jurassica underscores the
presence of angiosperms in the Jurassic and demands a rethinking of
angiosperm evolution.

Open access:
https://sp.lyellcollection.org/content/early/2022/01/04/SP521-2021-122