A team of researchers from the Missouri Botanical Garden and the University of Wisconsin–Madison identified an additional species of baobab in Madagascar. Scientists preliminarily classified the species, Adansonia bozy, as critically endangered due to its population size and threats like deforestation.
“It’s exciting that use of genetic data coupled with traditional taxonomic methods has finally led to the definitive distinction of this species, said Nisa Karimi, lead author and research associate at the Missouri Botanical Garden.
The Tree of Life
Baobabs belong to the genus Adansonia, which Carl Linnaeus named for French naturalist Michel Adanson in 1753.
Also known as the “upside down tree,” baobabs have thick horizontal branches that resemble tree roots. One of longest living trees, sometimes living more than 1,000 years, baobabs are also called the “the tree of life.”
Native to Africa, Australia, and Madagascar, baobabs are succulent trees that can grow to massive size. For example, the Sagole baobab in South Africa has a circumference of about 47 meters (154 feet) and stands 22 meters tall (72 feet). Girth measurements can fluctuate depending on rainfall. The trees use water stored in their trucks to flush new leaves at the start of the rainy season.
The largest flowering succulent trees in the world, baobabs flower for about a month each year. They produce white, yellow, orange, or red flowers, depending on the species. They bloom at night, attracting fruit bats, bushbabies, lemurs, or hawkmoths for pollination.
Baobabs in Madagascar
With this new discovery, there are now nine known baobab species, most of which are only found in Madagascar. The International Union for Conservation of Nature (IUCN) lists one species as critically endangered and two other Malagasy species as Endangered. The IUCN lists the remaining as “Least Concern,” but scientists believe “Near Threatened” is more appropriate given the declining populations.
Baobabs are of great ecological, ethnobotanical and spiritual importance across continental Africa and Madagascar, with over one hundred uses documented. The leaves, roots, flowers, fruit pulp, and seeds are all edible and have various traditional medicinal and religious uses. Baobabs also support people’s livelihoods through fruit harvest and the ecotourism they attract.
Scientists have studied baobabs in Madagascar for more than 100 years and have long believed the known list of Malagasy baobab species was incomplete, due to incomplete herbarium collections coupled with the logistical difficulties studying the trees.
“Historical collections from Madagascar are fairly limited, in part because some occur in regions difficult to access which makes them challenging for researchers to study, or populations have already been destroyed due to deforestation,” Karimi explained.
Solving the Puzzle
In particular, scientists were puzzled by one baobab species, Adansonia za. This widespread species grows in arid areas, savannah, and in deciduous and spiny forests. But scientists found physical and genetic differences among some populations of the species.
To solve the puzzle of this species, the team of researchers traveled to Madagascar to observe flowering baobabs. The large trees presented a challenge—Karimi had to learn to climb trees in order to collect their flowers for study. The team also collected tissue samples for DNA testing. Back in the U.S., they sequenced hundreds of genes to investigate the trees’ evolutionary histories.
A Distinct species
Their data revealed a distinct species of baobab, which the authors named Adansonia bozy. This species name was first used in 1910, but it eventually become synonymous with another species, Adansonia za.
Scientists previously identified the trees in this study, collected north of the Sambirano River region, as Adansonia za. The new genetic data showed that the Adansonia bozy trees are a distinct species more closely related to two other northern baobab species, A. perrieri and A. madagascariensis.
Adansonia bozy is limited to populations in the Sambirano River region that are genetically distinct from the rest of Adansonia za. Given the narrow distribution and presumed population size of A. bozy, scientists believe Adansonia bozy would most likely be classified as Critically Endangered following criteria put forth by the International Union for Conservation of Nature (IUCN).
“Hopefully this work will catalyze the much needed conservation and restoration efforts for this taxon, and many others, in Madagascar,” Karimi said.
The work also revealed other new information on baobab evolution in Madagascar, including surprising evidence of hybridization among other morphologically-distinct species and hints that the poorly studied northwest coast of Madagascar may house yet another new species of baobab.
“It is exciting to finally have a robust understanding of the evolutionary history of these iconic tree species; and an understanding of the likely role of gene flow in carrying floral traits among species,” said David Baum, senior author of the study and professor at the University of Wisconsin–Madison, who has been studying baobabs for nearly 40 years.
Why Taxonomy Matters
Accurately describing and cataloguing species in an ecosystem is foundational to studies of biodiversity and conservation. Taxonomists have done this work for centuries, using museum and herbaria collections to compare species’ traits. Today, scientists can integrate traditional observational biology with DNA sequencing and newer technological methods to better distinguish species.
Each year, the Missouri Botanical Garden scientists discover and name about 200 plant species new to science. That’s roughly 10% of all new plant species scientists describe worldwide annually.
Discovery is the first crucial step in plant conservation. Many newly-described species are critically endangered and at risk of disappearing. Once the species has a name, plans to try to ensure its survival can begin.
About the Study
About the study
“Phylogenomic analysis of Madagascar’s baobabs reveals admixed populations and supports resurrection of a previously described species” was published in Taxon in 2026 and is open access: doi.org/10.1002/tax.70176
The authors are Nisa Karimi (Missouri Botanical Garden, Corrinne E. Grover and Jonathan F. Wendel (Iowa State University), David A. Baum, University of Wisconsin, Madison.
Learn more about the Missouri Botanical Garden’s work in Madagascar. >
Written by Catherine Martin, Senior Public Information Officer
Leave a Reply