The world’s largest giant waterlily from the wetlands of Bolivia, a spiny fungus named after the Queen and a herb threatened with extinction by pigeon droppings are among more than 100 plants and fungi recorded as being new to science in 2022 by the Royal Botanic Gardens, Kew. Many of the discoveries, including a tall tree from Brazil’s Atlantic forest and a busy lizzie from Cameroon, are extremely rare, and one is already considered globally extinct. Two in five plants globally are estimated to be at the risk of extinction. Scientists at Kew said their efforts to name new species, working with partners, was part of a global effort to protect the planet’s biodiversity and also help humanity. On average 2,000 new species of plant and fungi are named each year, revealing the complexity of the tree of life as well as potential new sources of food, medicines and further innovation. “It’s easy to think we have a picture-perfect understanding of the natural world and all its plants and fungi, but as these annual lists show us time and time again, we’ve only really scratched the surface of discovery,” said Dr Martin Cheek, the senior research leader in Kew’s Africa team. “We cannot put a stop to the biodiversity crisis unless we know exactly what it is we are saving and where.” This year’s discoveries include the Queen’s hedgehog, a white mushroom with soft spines beneath the cap instead of gills, which DNA analysis has revealed to be a distinct European species and not the North American fungus it was once assumed to be. It was named in honour of Queen Elizabeth II. Dr Tuula Niskanen, the research leader in Kew’s fungal diversity team, said that an estimated 2m fungal species – more than 90% of all fungi – remained to be described by science. She said: “Fungi have remained such a mystery to us, compared to plants and many animals, because their cryptic lives mainly unfold hidden from our eyes and have been challenging to study with traditional techniques. Only in the last few decades, thanks to the arrival of DNA-based methods, have we started to understand the true diversity of this kingdom.” DNA analysis also confirmed the discovery of the giant Bolivian waterlily from the Amazonian wetlands, with leaves measuring up to 3.3 metres across. Two previously known species in the Victoria genus of waterlilies were both named in the early 19th century and have long been popular attractions at botanic gardens. Unknown to Kew’s researchers, a dried specimen of the giant Bolivian waterlily was kept in Kew’s herbarium for more than 170 years before being revealed as a new species. A new species of leafy herb, Gomphostemma phetchaburiense, is classified as “critically endangered” in the wild because its total population is less than 50 plants, all found at the mouth of a limestone cave in south-east Asia. The remaining plants are particularly threatened by the droppings of a nearby colony of rock pigeons. Another newly discovered plant has been deemed globally extinct before it could be formally confirmed as new to science and named. Saxicolella deniseae, a herb adapted to living in rapidly flowing water, was first collected on the Konkouré River of Guinea in west Africa, and named in honour of its collector, Denise Molmou. But a hydroelectric dam was constructed 20 miles downstream, producing a reservoir that swamped the falls on the lower reaches of the Konkouré and its tributaries, leading to the plant’s likely disappearance. Fieldwork this year found that another new discovery, Ipomoea aequatoriensis, is a relatively common weedy flowering plant in coastal Ecuador. It has been identified as a putative progenitor of the sweet potato – a major food crop in tropical America – and new knowledge of its relatives could lead to the breeding of improved strains to benefit humanity. Kew’s top 10 plant and fungi discoveries 1. Queen’s hedgehog (Hydnum reginae) A rare European species known in Britain only by the specimen which defines the species, which was found in the ancient beech woodland of White Down, Surrey. Previously known as Hydnum albidum, a name originating from North America, a collaboration of British field mycologists and Kew experts led to its description as a distinct European species. 2. Carpotroche caceresiae A tree from the Caribbean rainforests of Nicaragua and Honduras, named in recognition of the bravery of Berta Isabel Cáceres Flores (1971–2016), one of at least 123 environmental activists assassinated in Honduras between 2009 and 2016 for opposing the destruction of natural habitats. 3. The giant Bolivian waterlily (Victoria boliviana) A species confined to the wetlands of Amazonian Bolivia. A partnership of 16 Bolivian and European botanists working with Kew experts led to its naming as new to science. 4. Gomphostemma phetchaburiense A leafy herb with pink-purple flowers and a new species in the genus Gomphostemma, which means “garland of nails”. 5. Saxicolella deniseae A family of herbs known as “orchids of the falls” because they are adapted to living in aerated white water that is too harsh an environment for many plants. Some species are only found on one or two waterfalls. Despite their common name, they are not orchids. 6. Turkish “winter daffodil” (Sternbergia mishustinii) First collected from the seed of an unknown bulbous plant near Mersin in southern Turkey in 1997 by the Ukrainian naturalist Ruslan Mishustin of Kherson State University. Took years of research to be identified as a distinct species. Plants in the Sternbergia genus contain anti-inflammatory and antioxidant compounds, making this new species a potentially untapped source of medicine. 7. Cyanoboletus mediterraneensis A new species of Mediterranean bolete, the fungus was found in northern Israel and Sardinia, Italy. Parts of its brown cap and lemon-yellow stipe turn dark blue when handled or damaged. 8. Impatiens banen A threatened species of busy lizzie found in the Ebo Forest, Cameroon, and named after the Banen, the defenders of the forest and wildlife reserve. Ebo Forest is still threatened with deforestation despite the suspension of logging in 2020 following protests. 9. Ipomoea aequatoriensis For many years, the parent species of the well-known sweet potato has remained a mystery but scientists have found this flowering plant from coastal Ecuador is the closest relative. 10. Eugenia paranapanemensis A tree which grows up to 27 metres tall (equivalent to an eight-storey building) and only found in the last fragments of Brazil’s threatened Mata Atlântica rainforest. Critically endangered, only three mature trees have been found so far.