bush tomato

Herbarium Records Lead Bucknell Researcher to a New Plant Species in the Australian Outback

Australian botanists have newly identified Solanum nectarifolium, or the Tanami Bush Tomato, from historical specimens collected near the northern edge of the Tanami Desert.

Specialized Organs for Feeding Ants are First of Their Kind.

LEWISBURG, Pa. — A recent study led by Bucknell University Professor Chris Martine, biology, the David Burpee Professor in Plant Genetics & Research, has identified and described a new species of bush tomato with a special connection to ants — a taxonomic journey sparked by unusual specimens held in Australian herbarium collections.

The study, co-authored by a set of Australian botanists and Jason Cantley — the former Burpee Postdoctoral Fellow in Botany at Bucknell who is now Associate Professor of Biology at San Francisco State University — was published in the open-access journal PhytoKeys and underscores the critical role that natural history collections play in biodiversity science. The new species, Solanum nectarifolium, or the Tanami Bush Tomato, was named for the location of its original collection area — the northern edge of the Tanami Desert — and for the uniquely conspicuous nectar-producing organs on the undersides of its leaves.

The newly found Tanami Bush tomato from the Tanami Desert in Australia. — *Solanum nectarifolium,* a newly-described species of Australian bush tomato. Photo credit: Kym Brennan.

Martine first had an inkling that something was unusual about the plants from that region of the Northern Territory while working on a project with another former Burpee Postdoc, Angela McDonnell, now an Assistant Professor at St. Cloud State University. The pair included DNA extracted from two herbarium specimens representing Solanum ossicruentum, a species known as the Blood Bone Tomato that the Martine Lab described in the same journal in 2016, in an ongoing analysis meant to build a new bush tomato evolutionary tree.

“We couldn’t understand why the two collections of the same species kept showing up in different parts of the tree,” says Martine. “I had collected one of them and was certain that it represented Solanum ossicruentum, so I reached out to the person who collected the other one, David Albrecht, and asked whether he thought the plants he saw in 1996 at a place called Jellabra Rockhole could be something else.”

Albrecht, Senior Botanist at the Northern Territory Herbarium at Alice Springs, suggested that the best way to know would be for botanists to revisit that remote region of the northwestern Tanami Desert and see for themselves. Martine, who had participated in seven collecting expeditions to northern Australia since 2004, wasn’t disappointed.

“I was kind of hoping he’d tell me that,” Martine says. “Because I was already planning some new fieldwork in the Northern Territory and this would give me a great season to visit an area I had never been to before. But to really be prepared for a trip like that, I first needed to understand what other botanists had recorded and collected there in the past – and there is only one surefire way to do that: check what is in the herbarium collections.”

So Martine started by using the Australasian Virtual Herbarium (AVH), a database of every plant specimen held in every herbarium in Australia. He searched for collections made of Solanum ossicruentum and a similar species called Solanum dioicum in the northern Tanami, finding 15 records for specimens gathered as far back as 1971.

Map showing distribution of *Solanum nectarifolium* sp. nov. and *S. ossicruentum* based on accessions held at the Northern Territory Herbarium, Palmerston (DNA), the Western Australian Herbarium (PERTH), and the National Herbarium of New South Wales (NSW). Credit: Martine et al., 2025

“It was a really interesting distribution of points on the map, too,” Martine says. “These were far south of the other records for Solanum ossicruentum, with hundreds of miles of ‘empty’ country between the two clusters. I couldn’t wait to get to Australia to see what those Tanami plants looked like.”

In May 2025 Martine headed to Australia to meet his team for the trip: Cantley and paper coauthors Kym Brennan, Aiden Webb, and Geoff Newton, all associated with the Northern Territory Herbarium at Palmerston. But, first, Martine made a stop in another plant collection in the southwestern city of Perth.

“The visit to the Western Australian Herbarium was my first chance to spend a bunch of time with some of the actual specimens that I had earmarked based on the data in AVH,” Martine explains. “And what I saw there legit blew my mind.”

Every specimen looked similar to Solanum ossicruentum, except for a few subtle characteristics – and one thing that Martine had never seen in more than two decades of Outback botanizing.

Leaf of Solanum nectraifolium. — The veins on the leaf of *Solanum nectarifolium*, showing the extrafloral nectaries (EFNs). Phtoo credit: Kym Brennan.

“On the backs of the leaves, along the veins, were these visible round disks,” Martine notes. “They were each around a half-millimeter wide, really obvious, and the only bush tomato specimens that had them – we’re talking hundreds and hundreds of collections – were the ones from the northern Tanami.”

Martine thought they could be extrafloral nectaries (EFNs), non-flower organs on a plant that exude sweet liquid, typically as a means to attract ants that might protect the plants from herbivores. These were known to exist in a few Australian bush tomatoes, but those are tiny and have only been confirmed with microscopes. EFNs that could be seen without magnification would be something truly novel.

A few days later, Martine was in the herbarium at Palmerston and found the same pattern: more visible disks and only on plants from that same geographic area. Then he noticed that the most recent collection, from 2021, had been made by Kym Brennan – a renowned field biologist with an expertise in photography who was preparing for their trip in the next room.

“I ran in there and asked whether he remembered anything unusual about that collection – and before I could finish my explanation for why, he was already showing me an incredible photo of the leaves of that same plant. They were positively oozing with shiny, round droplets of nectar. And all from those disks on the veins.”

Oozing nectar from underneath the leaf of the newly found Tanami Bush Tomato. — The oozing extrafloral nectaries (EFNs) on the underside of the *Solanum nectarifolium* leaf. Photo credit: Kym Brennan

Eight days and more than 1000 kilometers of driving later the team arrived near Brennan’s collection site 50 kilometers southwest of the community of Lajamanu, right along the edge of the unpaved Lajamanu Road.

“This was more-or-less the same place where others had collected it in the early 1970s, so we were cautiously optimistic that we’d not only find it there again, but that the plants would have the flowers and fruits on them that we needed to describe this as a new species,” explains Martine. “But it’s a harsh environment and the abundance of bush tomatoes is often dependent on fire occurrence. Sometimes you get to a place and there is nothing but old gray stems. Other times there are more happy plants than you can count. In this case, it was the latter situation!”

Habitat of the Australian Tanami Bush Tomato. — Habitat of *Solanum nectarifolium* at the type locality. Photo credit: Aiden Webb.

The team got to work taking notes, making measurements, and shooting photographs. And then Cantley called for Martine to come over to the plant he was examining. There were ants all over the leaf undersides, avidly moving from disk to disk and probing them for nectar. Hypothesis confirmed.

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The collaborators decided on the scientific name “nectarifolium” – which translates to “nectar leaf,” for obvious reasons – and the English-language name Tanami Bush Tomato. Martine then contacted a few experts about the conspicuous nature of the EFNs and whether that has been seen anywhere else in the genus Solanum, a group of around 1200 species that includes the tomato, potato, and eggplant.

“As far as we know, this is the first Solanum species to be described as having extrafloral nectaries that you can see with your naked eye. That’s a pretty cool finding – and it all started with the examination of specimens that have been waiting in herbaria for as long as a half-century for someone to come along and take a closer look.”

Bucknell’s own Wayne E. Manning Herbarium, which holds approximately 25,000 plant specimens, now includes new samples of the Tanami Bush Tomato. But the official holotype remains at the Northern Territory Herbarium in Palmerston — almost 10,000 miles away from Bucknell’s campus.

Five different pictures of the newly discovered plant Solanum nectarifolium. — Habit and morphology of *Solanum nectarifolium*. Photo credit: Kym Brennan and Chris Martine.

“The Manning Herbarium may be small, but every specimen is a snapshot of biodiversity,” Martine says. “These collections allow us to study where species occur, how they’ve changed over time, and — in cases like this — even help discover new ones.”

The publication of the new species comes amid broader concern over the fate of natural history collections, such as Duke University’s recently announced closure of its herbarium housing more than 800,000 specimens. Martine and his colleagues agree that such closures could hinder future discoveries and conservation efforts.

Martine, a leading expert on Australian bush tomatoes, was recently elected president-elect of the Botanical Society of America. He will begin his term as president following the organization’s annual meeting in August 2026.

“It still doesn’t feel real and probably won’t until I start my term just after Botany 2026,” Martine says. “But I promise to do my best because plants are awesome and so are botanists.”

Original study:

Martine, C.T., Brennan, K., Cantley, J.T., Webb, A.T. and Newton, G. (2025). A new dioecious bush tomato, Solanum nectarifolium (Solanaceae), from the northern Tanami Desert, Northern Territory, Australia, with reassessment of S. ossicruentum and a change in the circumscription of S. dioicum. PhytoKeys, 268, pp.183–199. doi: https://doi.org/10.3897/phytokeys.268.169893

Scientists highlight safe access to the outdoors with naming of new plant species

The scientific name and English-language common name acknowledge the importance of maintaining equitable and safe access to outdoor spaces for all people.

Dr. Chris Martine, Bucknell’s David Burpee Professor, examining a *Solanum scalarium* plant at its only currently known location on the Escarpment Walk, Judbarra National Park, Northern Territory, Australia. Photo by Angela McDonnell

A new species of Australian bush tomato described from the Garrarnawun Lookout in Judbarra National Park provides a compelling example of the need to provide equal and safe access to natural places. Bucknell University postdoctoral fellow Tanisha Williams and biology professor Chris Martine led the study following a chance encounter with an unusual population of plants during a 2019 research expedition to the Northern Territory.

Martine, who has studied northern Australia’s bush tomatoes for more than 20 years, immediately sensed that the plants were representative of a not-yet-described species, so he, Angela McDonnell (St. Cloud State University), Jason Cantley (San Francisco State University), and Peter Jobson (Northern Territory Herbarium in Alice Springs) combed the local area for plants to closely study and make research collections from. The task was made easier by the fact that the Garrarnawun Lookout is accessible by a set of dozens of human-made stone steps running directly from the unpaved parking area to the peak of the sandstone outcrop – without which the new species might have otherwise gone unnoticed.

The botanists were able to collect numerous new specimens and have now published the new species description in the open-access journal PhytoKeys, choosing the name Solanum scalarium as a nod to the steps leading to the plant and the unusual ladder-like prickles that adorn the flowering stems. The Latin “scalarium” translates to “ladder”, “staircase” or “stairs.”

Photo of *Solanum scalarium*, a newly-described bush tomato species from the Northern Territory, Australia, showing the unusual ladder-like arrangement of prickles on male floral stems. Plants grown in the Rooke Biology Research Greenhouse at Bucknell University were closely studied by undergraduate student Jonathan Hayes (Biology ‘22) under the supervision of Drs. Tanisha Williams and Chris Martine. Photo by J. Hayes

“This Latin name does relate to the appearance of this species, how it looks,” says first-author Williams. “But it is also a way for us to acknowledge how important it is to create ways for people to interact with nature; not just scientists like us, but everyone.”

*Solanum scalarium*: immature green fruits enclosed in prickly calyx. Photo by Angela McDonnell

According to the authors, a recent study done by the Department of Local Government, Sport and Cultural Industries in Western Australia found that 8 in 10 people felt it is important to have access to natural spaces, both locally and outside of their current jurisdictions. However, one in three persons felt dissatisfied with the current outdoor spaces available to them and many identified barriers to access and participation in outdoor activities that include urbanization – which is especially credited for the growing number of Australians that lack outdoor experiences.

Importantly, the awareness of who has access and feels safe to participate in outdoor activities is being recognized throughout Australia and the lack of diversity in participation from culturally diverse and marginalized populations has been identified as an issue. Key indices such as ethnic background, socio-economic status, physical abilities and gender, are indicators of low outdoor recreation participation.

“These disparities of who are and are not participating and who feels safe and welcomed are artifacts of historic and current environmental and social injustices,” notes Williams. “To overcome these injustices and increase access and participation from diverse groups, intentional and targeted efforts are needed to provide a range of outdoor experiences that attract people from all of the 270 plus ancestries with which Australians identify with and special attention should be placed on groups historically excluded from outdoor spaces.”

Dr. Tanisha Williams, Bucknell’s Richard E. and Yvonne Smith Post-doctoral Fellow, on the rim of the Wolfe Creek Meteorite Crater during fieldwork in Western Australia in June 2022. Photo by Chris Martine

Also now known as the Garrarnawun Bush Tomato, Solanum scalarium is a distant cousin of the cultivated eggplant and a close relative to a number of other Australian species recently discovered by Martine and colleagues that were also published in PhytoKeys including Solanum plastisexum, named to reflect the diversity of sex forms across Earth’s organisms; and Solanum watneyi, named for the space botanist of the book/film The Martian.

The scientists hope that the naming of this latest new species highlights the importance of building community around natural spaces.

*Solanum scalarium* in the field, type locality. Photos by Angela McDonnell

“We suggest the use of Garrarnawun Bush Tomato for the English-language common name of the species,” the authors write, “In recognition of the Garrarnawun Lookout near where the type collection was made, a traditional meeting place of the Wardaman and Nungali-Ngaliwurru peoples whose lands overlap in this area.”

Access to nature is not just a concern in Australia.

“In the United States, where most of the authors of this paper are located, “access” is one thing but safety and equitability are another,” says Martine, “The U.S. National Parks Service reports that around 95% of those who visit federal parks are white. Meanwhile, African Americans, Latinos, women, and members of the LGBTQIA+ communities often report feeling unwelcome or unsafe in outdoor spaces.”

“If African Americans, for example, are already apprehensive in a country where they make up 13% of the population, it should be understandable that they are hesitant to be part of a community where they represent as little as 1% of participants.”

Dr. Tanisha Williams, Bucknell’s Richard E. and Yvonne Smith Post-doctoral Fellow, and Dr. Chris Martine, Bucknell’s David Burpee Professor, in Western Australia in June 2022. Photo by Claire Marino

Williams suggests that James Edward Mills, author of The Adventure Gap (2014) put it best:

“It’s not enough to say that the outdoors is free and open for everyone to enjoy. Of course it is! But after four centuries of racial oppression and discrimination that systematically made Black Americans fear for their physical safety, we must also make sure that we create a natural environment where people of color can not only feel welcome but encouraged to become active participants as outdoor enthusiasts and stewards dedicated to the protection of the land.”

Recent Bucknell graduate Jonathan Hayes, who measured and analyzed the physical characters of the new species using plants grown from seed in a campus greenhouse, joins Williams, McDonnell, Cantley, Jobson, and Martine as a co-author on the publication.

Research Article:

Williams TM, Hayes J, McDonnell AJ, Cantley JT, Jobson P, Martine CT (2022) Solanum scalarium (Solanaceae), a newly-described dioecious bush tomato from Judbarra/Gregory National Park, Northern Territory, Australia. PhytoKeys 216: 103-116. https://doi.org/10.3897/phytokeys.216.85972

Curious new bush species growing ‘bleeding’ fruits named by a US class of 150 7th graders

A class of 150 US 7th graders has helped select a name for a newly discovered plant, which amazes with its fruits that appear to be bleeding once they are cut open. Bucknell University biology professor Chris Martine and life science teacher Bradley Catherman challenged the students to come up with ideas for what to call the new Australian species last spring.

Looking for a way to engage local youngsters in biodiversity science, Martine scheduled a presentation to the collective 7th grade life science classes at Donald H. Eichhorn Middle School. As the day of his assembly approached, he started to think that the best way to generate interest might be to somehow allow the students to participate in the actual research he was doing in his lab at the time. Only, he knew there were few things he could do with 150 13- and 14-year olds sitting in a gymnasium.

“I emailed Mr. Catherman and I said, ‘How about we ask them to name a new species for me?’ explained Martine. “And then I showed up with live plants, preserved specimens, and my notes from the Outback – and we said, ‘Go ahead, tell us what to call this thing.'”

Nearly a year later, Martine and his co-authors, including two undergraduate students, have published the new species in the open access journal PhytoKeys. The news is coming just in time for the National Teacher Appreciation Day, thus giving tribute to Bradley Catherman, a life science teacher who is not afraid to step beyond the standard curriculum and make that extra step to actually engage his students with their studies.

“I was really impressed with Mr. Catherman’s willingness to work outside of the typical curriculum on this,” said Martine, “In an age when K-12 teachers are increasingly pressured to ‘teach to the test’ he is still willing to think creatively and try something unusual.”

Curiously, the new flowering bush species ‘behaves’ nothing like an ordinary plant. While its unripened fruits are greenish white on the inside when cut open, they start ‘bleeding’ in no more than two minutes. The scientists have even filmed a video short showing how their insides turn bloody scarlet at first, before growing darker, appearing just like clotting blood.

A week after the presentation, each of the students submitted an essay in which they suggested a name, explained the meaning, and translated it into Latin (the language that scientific names are required to be in). Catherman and Martine then selected the two best essays for the inaugural Discovery Prize, a new middle school science award established by Martine and his wife, Rachel.

“As you might imagine, the suggestions ran the gamut from the silly to the scientific,” said Martine. “But for every request to name the species after a favorite food, family pet, or Taylor Swift, there were many suggestions based on the data the students had been provided.”

According to Martine, a number of the students suggested names based on two characteristics of the plant’s berries: the ‘bleeding’ unripened fruits and the dry and bone-hard mature ones. Based on this, the plant will now be known as Solanum ossicruentum, best translated to Australian blood bone tomato, with “ossi” meaning “bone” and “cruentum” meaning “bloody”. The species belongs to the genus of the tomato.

The species is native to the sub-arid tropical zone of northern Australia. Martine collected the seeds, he grew his research plants from, during a 2014 expedition to Western Australia and the Northern Territory. However, specimens of the plant had actually been gathered for years before then.

“This is just one of thousands of unnamed Australian species that have been collected by dedicated field biologists and then stored in museums,” said Martine, who studied specimens of the new species in the Northern Territory Herbarium before hunting for it in the bush.

“There is a wealth of museum material just waiting to be given names – and, of course, the organisms represented by those specimens await that recognition, as well as the attention and protection that come with it.”

Luckily for Solanum ossicruentum, attention and protection are not too much of an issue.

“Not only is it widespread and fairly abundant,” said Martine, “but one of the healthiest populations occurs in Mirima National Park, a popular and easily-accessible natural area just outside the Western Australian town of Kununurra.”

“Plus, middle schoolers can be tough to deal with. I don’t think anyone in their right mind would mess with this plant, now,” the botanist joked.

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Original source:

Martine CT, Cantley JT, Frawley ES, Butler AR, Jordon-Thaden IE (2016) New functionally dioecious bush tomato from northwestern Australia, Solanum ossicruentum, may utilize “trample burr” dispersal. PhytoKeys 63: 19-29. doi: 10.3897/phytokeys.63.7743

New bush tomato species is the link between botany and an Oscar-nominated Hollywood movie

A new Australian bush tomato species, discovered by a team of researchers led by biology professor Chris Martine of Bucknell University, has been named after main character Mark Watney from the book and film The Martian. The authors, among whom is the undergraduate student Emma Frawley, have published the new species in the open-access journal PhytoKeys.

Martine announced the new name, Solanum watneyi, in The Huffington Post last year when he described it as a tribute to the heroic portrayal of Watney as a NASA botanist and engineer who saves himself with plant science expertise after being stranded on Mars.

In fact, Matt Damon’s botanist character impressed both the audience and the critics so much that it resulted in several Academy Awards nominations to the whole production team. The actor himself received a Golden Globe among many other prestigious recognitions including the BAFTA for Best Actor and the Critics’ Choice Award for Best Actor.

“This is a botanist portrayal that turns an unusually bright spotlight on authentic scientific endeavor,” Martine explains the choice. “Scientist heroes are already unusual in Hollywood, but a space-deserted protagonist who studies plants as a profession is something extraordinary.“

However, according to Martine, the decision to name the species after Watney also has some taxonomic relevance.

“The plant that Watney manages to grow on Mars is none other than Solanum tuberosum (the potato), a member of the same genus as our new species,” he says.

This connection was not missed by Andy Weir, author of the book-turned-movie and father of the Watney character, who expressed his approval of the name on his Facebook page.

“What higher honor could a botanist like Watney ask for than to have a plant named after him?” writes Weir. “And to have it be a relative of the potato as well? Perfect!”

Martine collected specimens of the new species during a six-week expedition to the Northern Territory of Australia with his wife, Rachel, and their two children. Rachel drew the illustration of the species that appears in the PhytoKeys paper.

In order to make sure the new species is not in fact a previously known and closely related Solanum species, the family team collected hundreds of seeds of both species. Thus, the plants could be grown and compared side-by-side in a research greenhouse.

In the summer of 2015, Bucknell undergraduate student Emma Frawley, class 2017, studied the plants, ultimately gathering and analyzing enough morphometric data to confirm the distinctiveness of Solanum watneyi. This is how Frawley, a double major in environmental studies and Spanish, became a co-author of the present paper.

The new species occurs in and around the western part of Judbarra/Gregory National Park, where it was occasionally encountered by regional botanists who nicknamed the oddball plant “Bullita” after the cattle station that once operated in the area.

“The nickname started being applied in the 1970s,” said Martine, who studied historical collections of the plant at the Northern Territory Herbarium. “But no one had yet done statistical comparisons between that plant and its similar relative.”

Watney is not the only one being recognized by the botanical community following the release of The Martian. In recognition of his botanist star turn, the Botanical Society of America has extended an honorary membership to actor Matt Damon, who portrays the space botanist in the film.

Note: Also listed as authors on the recent publication are Bucknell University Burpee Postdoctoral Fellow Jason Cantley and University of California-Berkeley Research Botanist Ingrid Jordon-Thaden.

Original source:

Martine CT, Frawley ES, Cantley JT, Jordon-Thaden IE (2016) Solanum watneyi, a new bush tomato species from the Northern Territory, Australia named for Mark Watney of the book and film “The Martian”. PhytoKeys 61: 1–13. doi: 10.3897/phytokeys.61.6995