Kew's successful year of discoveries

A very successful year for Kew

From rock faces in the snowy wastes of Antarctica, branches of monkey-puzzle trees in Chile, a pile of rotting leaves in the New Forest, to the forests and wooded grasslands of the tropics, new species have been found that vary from the microscopic fungal Rectipilus of the UK, to the massive, c.105 tonne Gilbertiodendron maximum trees of Gabon.

Most of these discoveries are the fruits of years of painstaking research partnerships, extensive fieldwork, dedicated expertise and lots of hard work. The top Kew producers this year, each with over 20 new species to their names, were John Wood, Iain Darbyshire and Eve Lucas.

The new species include crop wild relatives, sources of essential oils, sources of antibiotics and other medicinal compounds, potential new timbers, ornamental plant species for gardens and conservatories, and fungal species that underpin coniferous forest ecosystems in the North Temperate Zone.

Genera new to science

Four genera new to science were discovered in 2015. The first of these was Jaffrea, a shrub in the buckthorn family Rhamnaceae, which is specific to metal-rich soils in New Caledonia. It was published by Helen Fortune-Hopkins.

The second is a cryptic new shrubby legume genus, Arquita from the dry inter-Andean valleys of Ecuador, Bolivia and Peru, extending into northern Argentina. The genus comprises a set of five species formerly placed in a large unnatural assemblage traditionally known as Caesalpinia, and is clearly distinguished from close relatives in molecular analyses. It includes a new species, Arquita grandiflora, and a new variety Arquita trichocarpa var. boliviana, published by Gwilym Lewis and colleagues.

Legumes in South America and Africa

Among the other legume species published by Dr Lewis were a bright red, hummingbird-pollinated Brazilian jack bean (crop wild relative) of the genus Canavalia; a tree species of Amburana from NE Brazil with shiny red seeds with sap that is used locally as a soap; an overlooked itching Mucuna from Ethiopia; four Bauhinia from Brazil; and a Tephrosia from Peru. Brian Schrire published two new Indigofera species from a newly explored part of the Eastern Cape.

Heavyweight discoveries

The largest and heaviest of all new species described on planet Earth in 2015 was probably Gilbertiodendron maximum, one of eight threatened Cameroon-Congolian African rainforest canopy trees described by Xander van der Burgt and colleagues. Growing to 45 m tall, with a massive trunk to 1.4 m diameter, this Critically Endangered leguminous giant is endemic to Gabon. Its mass has been calculated as about 105 tonnes using allometric methods.

Six more new African rainforest trees, species of the Brazil-nut alliance Lecythidaceae, in the genera Crateranthus and Napoleonea, and also Rhaptopetalum cheekii, were described by past Director of Kew Sir Ghillean Prance, and his collaborator Carel Jongkind.

African successes

Topping the list for species discovery from Africa at Kew in 2015 was the family Acanthaceae. These tropical herbs of forest and woodland have stunning, showy flowers. One of the new species, Barleria hydeana, was collected by Mark Hyde, an actuary and amateur botanist in Zimbabwe who found this mauve-flowered subshrub in the Great Dyke, a linear geological formation with metal-rich rocks toxic to most plant species. This was one of 21 new Acanthaceae species published by Iain Darbyshire, Kaj Vollesen together with Ensermu Kelbessa in Kew’s now nearly complete Flora Zambesiaca series. Four additional new species of Acanthaceae were described from other tropical areas by John Wood.

Exploration of a previously understudied area of coastal evergreen thicket and woodland in the north east corner of Mozambique, highly threatened by a French petroleum giant, has led to the discovery of 36 new range-restricted species which are now in the process of being published, including Ochna dolicharthros, a 60 cm tall shrub with dark green glossy leaves and large, bright yellow flowers published by Frances Crawford and Iain Darbyshire.

Ectadiopsis thulinii (Asclepiadaceae-Apocynaceae), a spectacular flesh-flowered succulent from northern Somalia was only induced to flower by its author, Mike Gilbert, at his home in Brentford, after he had acquired cuttings from a botanic garden in Sweden! Other new African species included three pipeworts (Eriocaulon) from Sylvia Phillips, three sedges, a dock, a nettle and a daisy.

The discovery in Madagascar of Sartidia isaloensis, a new species of grass with C3 carbon fixation, exposes a fascinating story. Research by Bat Vorontosova suggests that the extensive grasslands of the central highlands, long thought to be composed of invasive African species and to have replaced forest destroyed by humans, are in fact largely made up of native C4 species of Aristida. C4 species are typically more tolerant of drought and high temperature. Vorontosova hypothesises that Sartidia, sister to Aristida, was once more widespread and common but has been outcompeted and displaced by Aristida, due to the increased frequency of fires associated with the arrival of humans on the island 1,500-2,000 years ago. Sartidia isaloensis survives only on the ledges of sandstone cliffs of the Isalo National Park, out of reach of annual fires. The only other Sartidia species from Madagascar is already believed extinct.

Brazilian collaboration pays off

The Kew-Brazilian botanical research collaboration was founded by Ray Harley over 30 years ago. Eve Lucas and collaborators from Brazil working on the myrtle family Myrtaceae had a particularly productive year. They published 22 new species of Eugenia and Myrcia, trees and shrubs from the Mata Atlantica (Atlantic Rainforest) of coastal Brazil. All of these are range-restricted species from a vegetation type which has been 90% cleared and is far more threatened than the more famous Amazon forest.

Eugenia and Myrcia are mega-diverse genera that are extremely challenging to identify in South America due to the high degree of superficial similarity. The former is the most species-diverse genus in Brazil. Myrtaceae are sensitive ecological indicators: high species diversity of myrtles in a forest is an indicator of good quality forest for conservation. In addition, pharmaceutical interest is growing in the vast range of essential oils that myrtles produce. Two new Rudgea species were published from the same Mata Atlantica forest habitat by Rubiaceae specialist Daniela Zappi. Other new discoveries from Brazil included two new species of the mint family and a Mollugo by Ray Harley, and a rock-dwelling nettle by Melanie Wilmot-Dear and Alex Monro.

What’s the story morning glory?

The morning glory and bindweed family Convolvulaceae rivalled Myrtaceae for discovery, with John Wood and colleagues publishing five species of Convolvulus from Eurasia, and 18 species of Ipomoea from Bolivia, among which, excitingly, is a relative of the sweet potato, Ipomoea batatas.

Amazing orchids

Among the new orchids discovered and published in 2015 is Dendrobium cynthiae, named by Andre Schuiteman for its grower in the USA, who acquired it from a dealer. The wild origin of the species is unknown, but it is thought to be New Guinea.

The largest orchid species published in 2015, 3 m tall, with three or four reed-like stems, is a slipper orchid, Selenipedium dodsonii, uncovered by Phil Cribb while researching a book on the slipper orchids of South America.

Four new Bornean species were published by Jeff Wood and colleagues: two Dendrobium, a Grosourdya and a Trichoglottis.

South East Asian discoveries

From the rainforests of SE Asia, five new species of liana, shrub and tree of primrose relatives Embelia, Maesa and Systellantha were published by Tim Utteridge and colleagues, who also, with Ian Turner, published five new custard-apple and ylang-ylang relatives, in the genera Alphonsea, Artabotrys, Meiogyne and Monoon, mainly from Malaysia and Indonesia. Three new species of insect-eating pitcher-plant, Nepenthes were published by me from a forest fragment in Luzon, and from new exploration in a proposed nickel mine in Halmahera, Indonesia.

Antarctic lichen

The snowy wastes of the deep Antarctic are too cold to host flowering plants, but lichens thrive on the bare rock of mountains that rise above the ice sheets, such as on Mount Kyffin. Lichens are collaborations of fungi and algae that can survive environmental extremes beyond those of flowering plants, and which produce chemicals of medical and commercial interest, such as rock digesting acids. Growing on one of the 40 lichen species at this site, a new genus and species of fungus, Bicoloromyces kyffiensis has been published by David Hawksworth and colleagues. Hawksworth has also co-published another new epiphytic lichen fungal species, Bryoria auracana from wild monkey-puzzle trees in Chile.

Fungal findings

While there are about 1,400 native vascular plant species in the UK, and no full new species to science has been found in many years, there are about 15,000 species of fungi, and new species are still being found by Kew scientists in collaboration with enthusiasts, through the Lost & Found Fungi project. This year Bryn Dentinger published Rectipilus afibulatus, found by Alan Lucas on rotting plant material in the New Forest. Larger, and possibly edible new species were also published by Bryn and collaborators from India and Pakistan: Austroboletus olivaceoglutinsus, Suillus marginielevatus, Boletus lakhanpali, and B. recapitulatus.

Meanwhile, from the conifer forests of North America and Europe, five new species of Cortinarius webcap toadstool were published by Tuula Niskanen and collaborators. Spending most of their existence as ectomycorrhizae on the roots of forest trees, these species are probably a critical element in supporting the existence of the conifer forests in which they occur.

Fossil discovery

The fourth new genus and species published by Kew scientists this year is a conifer tree of the cypress family, Cupressaceae. Scitistrobus duncaanensis was discovered from a single cone found on the Isle of Sky. Richard Bateman and colleagues described this fossil plant in the American Journal of Botany, placing it in the middle Jurassic, a new earlier period for the origin of the family.

Fighting extinction: the importance of discovering new species

Several of the new species published in 2015, like the Scitistrobus, are extinct or at risk of becoming so. One, Tarenna agnata, the forgotten Tarenna, in the coffee family Rubiaceae, which has not been seen alive for 50 years is a tree species of Ghana and Ivory Coast. The only records are from areas of dry forest habitat that has been reported as now having been cleared for agriculture or destroyed by fires. Another is the smallest known species thought to be published in 2015, a minute flowering plant of the waterfall-specific family Podostemaceae. The only known site for Ledermaniella lunda now has a hydro-electric dam built on it, and diamond mining has turned the river waters brown and turbid, inimicable to plants of this family, so it also is quite possibly extinct.

This case is not unusual. So many of the new species that we are discovering today are restricted to small areas and are at very high risk of global extinction, particularly from habitat clearance. Part of our responsibility as botanists discovering and publishing new species to science is to work with local partners to ensure that they do not become extinct. Our best hopes of doing this are through the Tropical Important Plant Areas programme (TIPAs): mapping and seeking to protect the most important areas for plants, in terms of concentrations of endemic, threatened and socio-economically useful species. Seedbanking through the Millennium Seed Bank Partnership is vital. Finally, finding and documenting uses for these new species wherever possible and making this information available, such as through the Useful Plants and Fungi Portal, will help to give incentives to local communities to protect natural vegetation as a resource that will provide them with benefits.