A giant water lily found in Bolivia has been identified as a distinct species that is the world's largest water lily, now known as Victoria boliviana.
A newly identified water lily species is also the largest of its kind, with lily pads up to 3.2 meters wide and flowers larger than a human head.
"The lily pads could definitely support the weight of a young child," says Natalia Przelomska, a member of the research team at Kew Gardens in the United Kingdom. In theory, the massive leaves can support an adult's weight of about 80 kilograms. "[However], I believe you'd need to put some kind of support in it to distribute their weight on the lily pad," Przelomska says. "Although we haven't tested it!"
Victoria boliviana is only the third species of giant water lily known to science.
Santa Cruz de La Sierra Botanic Garden and La Rinconada Gardens in Bolivia donated a collection of giant water lily seeds to Kew Gardens in 2016. As Carlos Magdalena, a Kew horticulturist and member of the research team, germinated and grew the seeds, he noticed they were distinct from the two known species of water lily. He traveled to Bolivia in 2019 to see the wild water lilies.
In north-eastern Bolivia, V. boliviana grows in freshwater rivers, floodplains, and ponds. Although it is unknown why water lilies grew to be so large, previous research suggests that their size may help them compete with other plants for sunlight.
"Because the biodiversity in the tropics is so high when an aquatic area opens up - for example, because rivers suddenly become larger due to a flood - the water lilies can thrive there because they grow so quickly and capture so much of the sunlight, outcompeting other plants," Przelomska says.
Przelomska and her colleague Oscar A. Pérez Escobar co-led an analysis of V. boliviana's genome as part of the new work. They discovered that it was slightly larger than the water lily species, Victoria cruziana, but smaller than Victoria amazonica. It has more than 4 billion base pairs.
"In general, a larger plant would not necessarily have a larger genome, but the largest water lilies happen to have the largest [lily] genomes, and we'd like to understand why," Przelomska says.
Further genetic analysis revealed that V. cruziana and V. boliviana split from V. amazonica about 5 million years ago, while V. cruziana and V. boliviana shared a common ancestor about 1 million years ago.
The team also discovered that V. boliviana appears to be more vulnerable to extinction than the other two species due to its smaller geographical range. As deforestation in the Amazon continues, all three species face increased threats.
"V. bolivana, like the other species, is under threat because the environment is deteriorating year by year," says Przelomska.
Reference: Frontiers in Plant Science, DOI: 10.3389/fpls.2022.883151