Researchers at Oregon State University have identified a spectacular new genus and flower species from the Middle Cretaceous period, frozen in time by Burmese amber.
“This isn’t a Christmas flower, but it’s a beauty, especially considering it was part of a forest that existed 100 million years ago,” said George Poinar Jr., professor emeritus at OSU School of Science (Oregon). State University). The findings were published in the Journal of the Botanical Research Institute of Texas.
“The male flower is tiny, about 2 millimeters wide, but has about 50 stamens arranged like a spiral, with anthers pointing to the sky,” said in a statement Poinar, an international expert on the use of plant and animal life forms preserved in amber for more information on the biology and ecology of the distant past.
A stamen consists of an anther, the pollen-producing head, and a filament, the stem that connects the anther to the flower. “Despite being so small, the detail that still remains is amazing,” Poinar said. “Our specimen was probably part of a group on the plant that contained many similar flowers, some possibly female.”
The new discovery has an empty egg-shaped floral cup, the part of the flower from which the stamens emanate; an outer layer consisting of six petal-shaped components known as tepals; and two-chamber anthers, with pollen sacs that are opened by valves with side hinges.
Poinar and collaborators from OSU and the U.S. Department of Agriculture named the new flower Valviloculus pleristaminis. Valve is the Latin term for leaf in a folding door, loculus means compartment, plerus refers to many and stamens reflect the dozens of male sexual organs of the flower.
The flower was wrapped in amber in the ancient supercontinent of Gondwana and was transported on a continental plate about 6,000 kilometers across the ocean from Australia to Southeast Asia, said Poinar.
Geologists have been debating just when this piece of land, known as the West Burma Bloc, separated from Gondwana. Some believe it was 200 million years ago; others claim it was more than 500 million years ago.
Numerous angiosperm flowers have been discovered in Burmese amber, most of which have been described by Poinar and a colleague from the state of Oregon, Kenton Chambers, who also collaborated in this research.
Angiosperms are vascular plants with stems, roots and leaves, with eggs that fertilize and develop inside the flower.
Since angiosperms only evolved and diversified about 100 million years ago, the West Burma Bloc could not have separated from Gondwana before, Poinar said, which is much later than the dates suggested by geologists.