It may look like a delicate, pretty white flower — but this newly discovered plant packs a stealthy bite.
The aforementioned flower is a new finding by University of British Columbia and University of Wisconsin-Madison researchers in the peer-reviewed journal Proceedings of the National Academy of Sciences of the United States of America (PNAS).
Insects get trapped in the flower's sticky hairs and the carnivorous plant sucks nutrients from the dead corpses.
The plant is called Triantha – a species of false asphodel – and it is the first new carnivorous plant to be identified by botanists in 20 years, explains a news release. It is notable for the unusual way it traps prey with sticky hairs on its flowering stem.
“Carnivorous plants have fascinated people since the Victorian era because they turn the usual order of things on its head: this is a plant eating animal,” said co-author Dr. Sean Graham, a professor in the department of botany at UBC. “We’re thrilled to have identified one growing right here in our own backyard on the west coast.”
Where does it grow?
Triantha grows in "nutrient-poor, boggy but bright areas" along the west coast of North America, from California to Alaska. For the study, the researchers investigated specimens growing on Cypress Mountain in North Vancouver.
“What’s particularly unique about this carnivorous plant is that it traps insects near its insect-pollinated flowers,” said lead author Dr. Qianshi Lin, a PhD student at UBCbotany at the time of the study. “On the surface, this seems like a conflict between carnivory and pollination because you don’t want to kill the insects that are helping you reproduce.”
“We believe that Triantha is able to balance carnivory with pollination because its glandular hairs are not very sticky and can only trap midges and other small insects, so that the much larger and stronger bees and butterflies that act as its pollinators are not captured,” said co-author Dr. Tom Givnish, a professor in the department of botany at the University of Wisconsin-Madison.
UBC notes that the research builds on work done previously in Graham's lab, which found that "Triantha lacked a particular gene that is often missing in other carnivorous plants."
Isotopic analysis of Triantha
To find out if the plant was "eating" insects, Lin attached fruit flies labelled with nitrogen-15 isotopes to its flowering stem. The label acted as a tracking device that allowed him to trace changes in nitrogen uptake by the plant.
He then compared the results with those from similar experiments on other species that grow in the same area, including a recognized carnivorous plant (a sundew) and several non-carnivorous plants as controls.
Isotopic analysis showed significant uptake of nitrogen by Triantha, which obtained more than half its nitrogen from prey –comparable to sundews in the same habitat, and other carnivorous plants elsewhere.
The study also found that the sticky hairs on the Triantha flower stalk produce phosphatase, a digestive enzyme used by many carnivorous plants to obtain phosphorous from prey.
The proximity of Triantha to major urban centres in western Canada and the Pacific coast in the United States suggests that other carnivorous plants – and many other ecological surprises – remain to be discovered, even in well-studied ecosystems.
But if you’re tempted to recreate the film Little Shop of Horrors or bring Triantha home to deal with pesky summer fruit flies, the researchers warn the plant doesn’t do well outside of its natural environment and advise admiring its quirks from a distance.
The full paper, “A new carnivorous plant lineage (Triantha) with a unique sticky-inflorescence trap,” will be published on Aug. 13 in PNAS.
