Wednesday, August 11, 2021

New species of “killer tobacco” found at Australian truck stop
by Liz Kimbrough on 11 August 2021

Found at truck stop in Australia, Nicotiana insecticida is the first wild tobacco species reported to kill insects.

The new tobacco does not appear to be carnivorous, but rather uses its sticky hairs to trap insects and protect itself from being eaten.

This sticky killer is one of seven newly named species of Nicotiana (wild tobacco) from Australia’s harsh, arid regions.

“The fact that we have only now found it,” said one of the researchers,“means that there are probably a lot more similarly interesting species out there to be found.”


At a truck stop along a Western Australian highway, researchers noticed an unfamiliar wild tobacco plant. Covered in sticky hairs, the plant appeared to be a mass grave for small insects — flies, gnats, and aphids, which met an untimely death in the tobacco’s fetid liquid armor.

After shepherding its seeds from the truck stop to the greenhouses of Kew Gardens in London for cultivation, scientists found that the second generation continued its murderous ways on foreign soil, making it the first wild tobacco species reported to kill insects.

The tobacco, previously unknown to science, has been named Nicotiana insecticida. Its description was published today in the journal Curtis’s Botanical Magazine.

Nicotiana insecticida, a wild tobacco newly named by science. Photo by Maarten Christenhusz

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Insects caught in the glandular hairs of Nicotiana insecticida. Photo by Maarten Christenhusz.

“Nicotiana insecticida demonstrates well the adage that ‘tobacco kills,’” Mark Chase, a scientist at the Royal Botanic Gardens, Kew, said in a press release, “although in this case it is insects that become ensnared on its sundew-like glandular hairs and die.”

Because N. insecticida does not appear to be “eating” the insects like the sundew plant (Drosera spp.), which captures insects with sticky hairs and dissolves them for food, it is not considered carnivorous. The tobacco’s gooey glands, researchers believe, are simply there to protect the plant from being munched on, and are quite effective.

“Many plants have sticky glands, but generally they do not kill insects in such numbers,” Chase told Mongabay in an email. “Tomatoes (a relative of the tobaccos) have glands that trap and kill some insects, but not in these numbers and not so regularly.”

Nicotiana insecticida captures insects to protect itself from being eaten. Photo by Maarten Christenhusz.

The sticky killer tobacco is one of seven species of Nicotiana (wild tobacco) newly named by scientists from the Royal Botanical Gardens, Kew, Australia’s Curtin University, and the University of Vienna. These new plants were described following eight years of fieldwork in the Australian outback by Chase and Maarten Christenhusz, senior researcher at Plant Gateway Ltd., with offices in the U.K. and the Netherlands. Their research explores the way plants adapt to the harsh, arid conditions of Australia’s dry regions.

“The arid parts of Australia, which is most of the continent, have been thought of as almost barren with limited plant diversity, but in recent years these poorly studied areas have yielded many new and unusual species,” Chase said in a press release.

Along the salt lakes between the Western Australian wheat belt and the dry central region, scientists found Nicotiana salina (salty tobacco), and in the Northern Territory, Nicotiana walpa, named from the local Aboriginal word for wind (in Pitjantjatjara, the language of the Anangu people). The wind plant only grows after storms dampen the desert; otherwise, the seeds lay dormant in the soil.

“The fact that we have only now found [these species],” Chase told Mongabay, “means that there are probably a lot more similarly interesting species out there to be found.”

Nicotiana insecticida flower. Photo by Maarten Christenhusz.

Citation:

Chase, M. W., & Christenhusz, M. J. M. (2021). Nicotiana insecticida: Solanaceae. Curtis’s Botanical Magazine. doi:10.1111/curt.12402

Liz Kimbrough is a staff writer for Mongabay. Find her on Twitter: @lizkimbrough_

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