Top 10 plant and fungal species named new to science in 2024

Scientists from the Royal Botanic Gardens, Kew and their partners reveal their pick of the top 10 plants and fungi named new to science in 2024.

From marzipan-scented lianas to an entirely new genus and family of plants, the annual list is a reminder of the many unknowns waiting to be discovered, as well as a call to action inspiring a new generation to take an interest in plant and fungal taxonomy.

In the past 12 months, Kew’s scientists and collaborators have named approximately 149 plants and 23 fungi from virtually every corner of the globe. Among these are new fungi from Europe and Africa, climbers from tropical Asia, and five beautiful orchids from across Indonesia.

Other highlights include a bracket fungus found in Buckinghamshire in the UK, a ghostly palm from the island of Borneo, and an enigmatic family of plants without the ability to photosynthesize, that relies instead entirely on mycorrhizal fungi for sustenance.

Where possible, Kew works with international partners to protect plants in situ, that is in their natural habitats, by incorporating them into a network of Important Plant Areas (IPAs). Where in situ conservation is impossible, plant material may be collected and expertly propagated by Kew’s horticulturists to include in the Living Collections at Kew Gardens in West London, or by conserving their seeds at the Millennium Seed Bank at Wakehurst, Kew’s wild botanic garden in Sussex.

Unfortunately, several of the new species are already at risk of extinction, such as a Critically Endangered species of Vietnamese liana that is threatened by the clearing of its natural habitat for the manufacture of cement. Last year, Kew’s scientists warned in the State of the World’s Plants and Fungi 2023 report that as many as three in four undescribed plants are already threatened with extinction.

Dr. Martin Cheek, Senior Research Leader in RBG Kew’s Africa team, says, “The sheer privilege of describing a species as new to science is a thrill that not many will ever get to experience. Sadly, this delight is increasingly being overshadowed by the many threats that plants face as a direct consequence of human activity.

“The devastating reality is that more often than not, new species are being found on the brink of extinction and its a race against time to find and describe them all. We urgently need more funding, training, and public awareness of plant and fungal taxonomy. Biodiversity loss is a crisis that affects us all: every unknown species we lose could have been a potential new food or new medicine that we never even knew existed.”

The scale of the challenge is immense: each year scientists globally describe on average 2,500 new plants and 2,500 fungi, and estimates indicate there could be as many as 100,000 plant species left to uncover. For fungi, it is a much higher estimate, between two and three million species unknown to science.

Anna Bazzicalupo, Research Leader in Comparative Fungal Biology at RBG Kew, says, “Identifying new species of fungi is a colossal but increasingly important task as we estimate more than 2 million species are waiting to be described, and an overwhelming number of them are likely threatened with extinction, meaning they may disappear before they are even recognized.

“There have been many positive developments in the field this year, however. Key among them was the Fungal Conservation Pledge at COP16, which will help prioritize the protection and conservation of fungi and put the kingdom of Funga firmly on the map.”

Here are the top 10 weird, wonderful, and intriguing species named new to science in 2024:

1. A ‘ghost palm’ discovery 90 years in the making

Although long used in western Borneo (Malaysia and Indonesia) by local Iban communities for basketry and for its edible young shoots, this highly distinctive rattan or climbing palm has remained without a scientific name until now. The earliest-known herbarium specimen dates back over 90 years and it has been suspected to be a new species more than 40 years ago.

Local communities call the plant wi mukoup or wee mukup, and it is only known from three locations in or near protected rainforest habitats. It has now been given the scientific name of Plectocomiopsis hantu.

The name hantu is the Indonesian and Malay word for ghost, due to its ghostly appearance, with white undersides to the leaves and gray stems, and because scientifically it is mysterious and still incompletely known. A formal description does, however, mean it is now visible to future conservation efforts.

2. Three new fishy fungi from Europe and North America

There are about 800 described toadstool species in the genus Russula globally, recognized by the absence of a veil, their brittle gills, and apple flesh-like stalks that often smell of fish. Like many toadstools, they are mycorrhizal, their hyphae connecting with the roots of plants, often trees, in a mutualism. And though many of these species are edible, some are toxic to humans.

A study by a group of 13 scientists from Slovakia, Sweden, Germany, U.S., and Kew, used DNA sequencing to distinguish three new species of Russula that have long been a puzzle to separate. Virtually indistinguishable to the naked eye, it was their microscopic features, DNA, and geographic and ecological separation that marked them out as unique species. The species are:

• Russula lapponica of mixed woods of birch, spruce, pine, aspen, elm, hazel in Swedish and Norwegian Sápmi, also Estonia.
• Russula neopascua among alpine willow of the high Rockies in Colorado and Montana.
• Russula olympiana with the same range, extending to the Pacific Northwest and British Colombia, in mostly coniferous forest.

3. The ‘black-souled’ Colombian Aphelandra

This newly described plant is related to the widely cultivated Brazilian zebra plant (Aphelandra squarrosa) that adorns many households around the globe. However, it hails from the dry forests of north-west Colombia, and it is named ‘black soul’ due to its black heartwood.

This deciduous shrub grows up to 5 m tall in its natural habitat, at altitudes of up to 1,000 m. It boasts spectacular pink flowers 4 to 5 cm long, with up to 110 flowers in each spike from November to March. Each spike is up to 32 cm long, giving it great potential as a house plant. Unfortunately, it is threatened by habitat clearance due to human activities.

It is one of many new acanths (plants from the Acanthaceae family) described as new to science by a partnership of two botanists working on Colombian acanths and has been given the formal name of Aphelandra almanegra. The name almanegra is a combination of the Spanish words for soul and black.

4. Afrothismiaceae: A new African family with a feeding quirk

Most flowering plants have green leaves and depend on sunlight to make carbohydrates (sugar molecules) through photosynthesis, while relying on their roots and mycorrhizal fungi to boost the uptake of minerals in exchange for some of those sugars.

Some plants, however, have learned to ‘cheat’ their fungal partners and take all their needs from them, losing in the process their green pigmentation. They only appear above ground to fruit and flower, such as the famous ghost orchid.

Scientists have now named an entirely new family of plants with this peculiar feeding quirk, calling it Afrothismiaceae after the genus Afrothismia. Afrothismia species are all confined to continental African forests and until now were thought to be members of the Thismiaceae family.

DNA studies, however, strongly pointed to this genus being contained in its own family. All these species are extremely rare or even extinct and most have only been recorded once. Of the named species, most appear in Cameroon.

5. A star-studded mystery of jumping genes and rule-breaking

The discovery of this new herb from Guinea in West Africa has caused something of a stir among botanists. Officially named Virectaria stellata, the species belongs to the genus Virectaria in the family Rubiaceae, one of the largest families with thousands of species. Oddly enough, V. stellata is characterized by star-shaped (stellate) hairs, which has never been seen in this family before.

Even more intriguingly, these hairs are a special type of stellate which occur in a group of species in the genus Barleria in the unrelated family Acanthaceae. It appears the genes for producing stellate hairs may have jumped over from one family to another, possibly via sap-feeding insects.

The mysterious plant was discovered by a team of Guinean and Kew botanists from remote sandstone cliffs of the Fouta Djalon in Guinea, West Africa, as part of a program to discover and protect the most Important Plant Areas (IPAs) in Guinea.

6. Three new tooth fungi from the UK

When you turn over a toadstool, you are likely to see gills or pores beneath the caps that act as a means of spore dispersal. But this is not the case for several fungi, particularly those in the genus Phellodon, where the gills have been replaced by teeth-like structures (as seen in the attached image).

Scientists typically consider fungi in this genus to be an indicator of overall good quality forest habitat due to their sensitivity to nitrate pollution. Unfortunately, they are disappearing across Europe and species identification has been a problem, further complicating efforts to conserve them. But the good news is that DNA sequencing has now revealed four new Phellodon species, three of which occur in the UK.

Phellodon castaneoleucus, an ectomycorrhizal fungus that forms partnerships with the living roots of sweet chestnut, beech, and oak, was described from a wooded heathland near Royal Tunbridge Wells. P. frondosoniger, another ectomycorrhizal fungus partnered with broadleaved trees such as oaks but with black caps was described from Crown Estate land near Windsor. And finally, P. aquiloniniger, which also boasts a black cap, was found in Scottish pine forests such as Abernethy Forest.

7. Lonely liana laments extinction risk from cement manufacture

This is a new genus and individual species endemic to Vietnam, in the tropical liana family Malpighiaceae. The genus is named Chlorohiptage after its flowers, which are uniquely green rather than the usual yellow seen in the family.

At present, the Vietnamese and Kew authors are at a loss as to what kind of insect would pollinate these green flowers. They do, however, note that its limestone karst habitat is being cleared for quarries to make cement that is mostly sold overseas.

The scientists, therefore, consider the new species Chlorohiptage vietnamensis to be the only known species of its kind, and have assessed it as Critically Endangered.

8. An orchid bonanza straight from Indonesia

Consisting of more than 17,000 individual islands, Indonesia is home to some of the most spectacular biodiversity in the world. And yet, many of the plant species scattered across the country still remain unknown to science.

However, thanks to a long-standing collaboration between Indonesian and Kew orchid specialists, five new and quite spectacular orchids from various sites across the archipelago have been published in 2024. The species are:

• Coelogyne albomarginata from Sumatra.
• Coelogyne spinifera from Seram.
• Dendrobium cokronagoroi from West New Guinea.
• Dendrobium wanmae from West Papua Province and assessed as Critically Endangered.
• Mediocalcar gemma-coronae, also from West Papua Province, and has been assessed as Endangered.

9. A marzipan-scented liana named after a Guinean botanist

Keita deniseae is a new species and genus of African rainforest liana, characterized by the strong smell of marzipan given off by its roots and stems when scraped.

The type specimen of K. deniseae was collected in the Boyboyba forest of Guinea, where the plant climbs into the canopy with strange, hooked structures and bears large, edible fruit. The plant’s name honors its collector, Guinean botanist Denise Molmou, who in 2018 discovered the rare and now most likely extinct “orchid of the falls,” Saxicolella deniseae, or ‘Denise’s Saxicolella’.

Meanwhile, the genus Keita was named after the late Professor Sékou Moussa Keita, a champion of plant conservation in Guinea. In Maninka, the clan name Keita can be interpreted as ‘blessing’.

10. Threatened by cinnamon farming, a moth-pollinated liana from China

Cheniella is a genus of tendrilled forest lianas in the bean family that occur from India to SE Asia. A collaborative taxonomic revision by Kew and Chinese scientists has revealed three new species in the genus (taking the total up to 15), all of which occur in southern China, Cheniella’s center of diversity. Unfortunately, all three species are under threat from human habitat clearance.

One of the new species, C. pubicarpa, is recognizable for its hairy pods and angled stems and is known from only two individual limestone hills.

Another, C. longistaminea, flowers only at night and is pollinated by moths, featuring stamens twice as long as its petals. It boasts stems up to 80 m long and climbs up to 30 m into the canopy, and its native forest habitat has been replaced by trees planted for timber and carbon sequestration (e.g. Chinese fir) as well as Chinese cinnamon (Cinnamomum cassia), the main source of cinnamon in North America and an important element of traditional Chinese medicine thought to have been used in embalming Egyptian mummies.

Runners up and honorable mentions:

11. New species of fungus found on dead willows in the UK

This new species is a small, white bracket fungus measuring 2 to 4 cm in diameter, officially named Fomitopsis solaris. Found here in the UK on dead willow (Salix) wood, the fungus is known from locations across Europe, from Sweden to France, with a few verified records from Argentina, Canada, and Israel.

F. solaris is a prime example of a previously known species of fungus being split into multiple new species based on the sequencing of its DNA. In the UK it has been observed in Berkshire, Buckinghamshire, Hampshire, Kent, Somerset, and Surrey in wet woodlands.