By Carolyn Webb
Many humans enjoy dining on shellfish, but have you ever heard of a plant with a hankering for seafood?
During a trek into a remote Malaysian jungle, a Melbourne botanist found a previously unknown carnivorous species that, to his astonishment, had eaten a crab.
Dr Alastair Robinson, a world expert on carnivorous plants, said it was “pretty spectacular” to see the remains of a crab, as well as of bits of giant millipedes, inside one of the tropical plants’ “pitchers”.
The pitchers, attached to the plants by tendrils, are jug-shaped organs filled with digestive enzymes.
The never-before documented species Robinson named was also unique for the orange hair covering its pitchers, stems and leaves, that resembled orangutans’ fur.
Robinson, the head of biodiversity services at Melbourne’s Royal Botanic Gardens, has named dozens of other new species in his global expeditions, but had never seen one that had eaten a crab. “It was amazing,” he said.
Dr Alastair Robinson in a jungle in Sabah, Malaysia, with the newly identified tropical pitcher plant Nepenthes pongoides.
Robinson, who as a boy was a fan of the 1980s macabre comedy musical, Little Shop of Horrors, said he was yet to come across a species that ate humans, like the fictional plant, Audrey II.
In reality, most carnivorous plants eat insects, but some larger pitcher plants can consume rodents.
“They’re big enough to inadvertently trap small mammals, and when they do, it’s Christmas,” he said. “They’re real opportunists, I think it’s fair to say.”
The species, Nepenthes attenboroughii, which Robinson and other scientists first recorded in the Philippines in 2007 and named after Sir David Attenborough, was found with a terrestrial shrew — a small, mole-like mammal — drowned in one of its pitchers.
And another species, found in Borneo and called Nepenthes rajah, had rats found in it a couple of times, Robinson said.
He and scientists from Malaysia’s Sandakan Herbarium documented the new species on a mountain in Sabah state, in eastern Malaysia, in May last year.
Robinson said that before the COVID-19 pandemic, he saw a photo of the plants in a Malaysian book that gave a species name in the caption that he knew was incorrect.
Robinson believed it was a new species but the pandemic postponed a visit until 2023.
Parts of a crab, the purple bits, were found inside the pitcher of newly named species Nepenthes pongoides.
The 2023 trek was funded by the US-based International Carnivorous Plant Society.
It took three days to reach the site from the Malaysian capital, Kuala Lumpur, by plane, 4WD, ferry and two days of walking.
The find can be revealed now after an official publication in the Australian Journal of Botany.
Robinson said the plants were low-growing, with leaves up to 40 centimetres long and pitchers equally tall, with 20-centimetre-diameter openings.
The plants’ orange hairs resembled orangutan fur. It was “the most extensive covering of hair of any pitcher plant found”, Robinson said.
The scientists had also spotted an orangutan in a tree the night before the discovery, and so they named the plant species Nepenthes pongoides.
“Nepenthes” is the term for a tropical pitcher plant, and “pongoides” comes from the scientific name for orangutans, Pongo.
Robinson said a common name had yet to be assigned but he favoured “orangutan pitcher plant”.
Just 39 individual mature plants were found, making the species critically endangered and at extreme risk of extinction.
Giant millipede remains being digested in the pitcher of Nepenthes pongoides in Malaysia.
Illegal poaching is a major threat.
In addition, the ground underneath the plants is rich with nickel deposits and there are oil palm plantations nearby.
Logging and wildfires are also threats.
Robinson said publicly naming and documenting the species was critical to its protection.
Botanist Dr Alastair Robinson at Melbourne’s Royal Botanic Gardens with Nepenthes truncata, a carnivorous species found in the Philippines. Credit: Jason South
He hopes the Malaysian government offers further protection by naming the site a national park. This could lead to ranger patrols and seeds being collected so the plants could be grown elsewhere.
Robinson said pitcher plants adapted to their conditions to survive.
One plant, Nepenthes lowii, native to Borneo, has evolved to be a “toilet to tree shrews”. It produces a waxy material that is carbohydrate-rich and attracts the shrews to feed, and they poo into the pitcher while they’re eating it. And the poo, in turn, feeds the plant.
Another species, Nepenthes ampullaria, found in Sumatra, peninsular Malaysia, Borneo and West Papua, has even turned vegetarian. “It has these little tubby pitchers that sit on the ground, and leaves that fall into them get digested over time.”
Robinson said he admired carnivorous plants for surviving in often harsh environments. All carnivorous plants come from areas that don’t have good soil, he said. “It’s a competitive advantage if you can acquire nutrients in different ways, and one of those ways is carnivory.”
In Sabah, Robinson’s team collected specimens – only as cuttings to avoid harming the small population – that are now deposited in Melbourne’s Royal Botanic Gardens Herbarium and in the Sandakan Herbarium.
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