Oldest flowering plant

The earliest angiosperm (flowering plant) currently known to science is Florigerminis jurassica ("Jurassic flower bud"), which dates back 164 million years, to the Jurassic period. The new species (and genus) was scientifically named and described in the journal Geological Society on 6 January 2022 from a 4.2-cm-long (1.7-in) fossil discovered in China's Inner Mongolia region. It consists of a stem, a leafy branch, a bulbous fruit and a tiny flower bud, circa 3 mm2 in size. This is presently the only recognized angiosperm species of any kind dating back as far as the Jurassic.

Prior to this, two other notable fossil angiosperm species had been put forward for this record. The first of these was Archaefructus sinensis ("ancient fruit from China"), whose discovery had been publicly announced on 3 May 2002. Approximately 125 million years old (Early Cretaceous), it was found in a slab of stone in north-east China, and in life it is believed to have thrived in clear shallow water, with its flowers and seeds extending above the surface.

This species' claim was superseded 13 years later by Montsechia vidalii, a Spanish fossil aquatic angiosperm dating back approximately 130 million years (Early Cretaceous again), which superficially resembles modern-day coontails (genus Ceratophyllum), and whose evolutionary significance was publicized in 2015.

There are also various fossil angiosperm pollen samples dating back approximately 134 million years (Early Cretaceous yet again), but these are not megafossils like the two documented above.