A rare species of “waterfall orchid” declared extinct in the wild – Verve times

A team of botanists from Guinea and the Royal Botanic Gardens in Kew, UK, has died dying for a plant of the genus Saxicolella, which is endemic in one place in Guinea. A sad discovery was made by botanist Kew Dr. Martin Cheek, who examined the last known coordinates of the plant using Google Earth satellite scans after a taxonomic survey of the genus Saxicolella published this week in a scientific journal. Kew Bulletin.

The article introduces several new species for science, one of which is Saxicolella deniseae or ‘Denise’s Saxicolella’. Unfortunately, the latest satellite images from November 2021 reveal that the plant was submerged in water from a hydroelectric dam only 30-40 km downstream. According to Dr. Cheeka’s development actually led to the extinction of the plant.

Eight species of the genus Saxicolella occur in the “orchid waterfall” family, which includes about 300 species, mostly in the tropics. Although they are not orchids, they are all limited to falls and rapids. Officially known as Podostemaceae, it is a family of waterfall plants limited to living in fast-moving and aerated waters, many of which are only now described in science. The plants appeared prominently in an episode of the BBC documentary series The Green Planet earlier this year, when naturalist David Attenborough called the family “waterfall orchids”.

Saxicolella deniseae was believed to be endemic in a single location along the Konkouré River in the Republic of Guinea in West Africa, where there are now several newly built hydropower plants supplying energy to the region. The only known specimen was collected (and named after him) by botanist Denise Molmou in 2018 – the first and probably the last scientist to see this species in the wild – under the Guinea Tropical Important Areas (TIPAs) program – an international effort to conserve tropical plants. biodiversity in the wild.

Dr. Martin Cheek, head of research at RBG Kew’s African teams, says, “We know that many plant species have become extinct recently, but this case shows how unexpected and sudden extinction can be. In Africa, ‘orchid waterfall’ species are often limited to a single waterfall, sometimes two, three or four on the same river. In this case, due to the dam, there are now several waterfalls along Konkouré, where this species may also have occurred, under water reservoirs, so it seems quite certain that this species has become extinct. It probably happened last year, which we didn’t know about when we checked how close the tank had progressed. “

Unfortunately, botanists have not been able to collect and store any viable seeds that could preserve the genetic material of S. deniseae. Experts faced travel restrictions between 2020 and 2021 due to the COVID pandemic, and Kew’s partners at Guinea’s National Herbarium prevented internal unrest in the September 2021 military coup. Cheek’s attempts by local botanists to reach the race would be further hampered by the extremely poor condition of the surrounding roads.

Denise Molmou, a botanist from the UGAN-National Herbarium of Guinea, says that “although it is a great honor for me to be named after a species I discovered in the wild, it is really sad that it is almost certainly extinct. I’ll see if we can find him in other waterfalls, even if the chances of finding him alive aren’t very high. “

The waterfalls on the tributary of the Konkouré River, where S. deniseae was found, were targeted because there were no known collections of this plant along most of the river, despite the existence of many waterfalls visible on Google Earth. This indicated that no one had studied the biodiversity of the plants at the waterfalls of this river.

In order to prevent the extinction of biodiversity in the wild, it is important that botanists carry out full studies of plants in waterfalls in tropical areas, especially before the hydroelectric power plant construction plan. Kew botanists believe that exploring a waterfall for “orchid waterfall” species takes only one or two hours, followed by another time to see if they are in danger of extinction, whether or not they are new to science. Sadly, formal studies are rarely conducted before such projects begin.

Dr. Cheek says, “There’s still a very small chance that this species will survive somewhere. But because this water project and others upstream flooded about 150 km of the Konkouré River and also 30 km of the tributary where this species occurred, it is very likely that this species is lost forever. We will keep looking. “

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