Beauty may be in the eye of the beholder, but a newly discovered orchid is likely not the best choice for many as a centerpiece of the bodice.
Gastrodia agnicellus, from the forests of Madagascar, has received the label of the ugliest orchid in the world by botanists at the Royal Botanic Gardens, Kew, in the United Kingdom.
And yet the plant is fascinating, unusual among orchids, and indicates what we may be missing from what is hidden in the undergrowth of the forest.
In turn, this highlights the importance of protecting the environment: even though it has only just been discovered, G. agnicellus it is already considered an endangered species.
It seems reasonable that the plant would not have been recognized until September last year. G. agnicellus it spends most of its life buried underground, emerging in August and September only flowering and fruiting under the leaf humus in the forest floor before disappearing underground again.
These flowers are also small, only 11 millimeters long (0.43 inches), and are indescribable against ground debris, ranging in color from brown to white. Still, the flower had been found before; is that no one has noticed until recently.
Flowering G. agnicellus, after clearing the leaf litter. (J. Hermans, Curtis’s Bot. Mag., 2020)
“New material Gastrodia agnicellus, found near Ifanadiana in southeastern Madagascar in the 1990s, was recognized as belonging to the genus and was initially considered to be G. madagascariensis“, wrote the botanist Johan Hermans of Kew Gardens in the official description of the species.
“During an excursion to Madagascar in December 2017, in Gastrodia with high and dry infructescences was first noticed in the Ranomafana area. During a more recent trip, in September 2019, the same place was visited again and, after extensive research, some fruiting inflorescences were found in development.
“It wasn’t until a layer of leaves was lifted that a small number of flowers were also discovered. It soon became apparent that the flowers were quite different from those of the recently validated ones. G. madagascariensis and that it was an unrecognized species. “
Orchids were found in deep shade in a moist evergreen forest, at the base of trees, hidden among flowers, moss and leaf litter. Still, they emitted a pleasant, soft, rose-like aroma, Hermans wrote, which grew stronger at warmer temperatures.
After pollination of the flowers, the stem becomes longer, probably helping the seeds to disperse.
The fruits are fully developed. (J. Hermans, Curtis’s Bot. Mag., 2020)
And, as with other members of the Gastrodia genus, the orchid plant has no leaves; in fact, it has no photosynthetic tissue.
This is because this plant is a holomycotroph, a type of orchid that relies solely on a relationship with the fungus to get the nutrients it needs to survive. The fungus extracts nutrients such as soil carbon or other plants, and the orchid makes out of the fungus what it needs.
All orchids depend on a relationship like this with fungi at some point in their life cycle, but as most species grow into adulthood, their dependence on fungi fades. It is not exactly clear what the fungus derives from the relationship, but in many cases it is part of a mycorrhizal network, where the fungus exchanges nutrients with other plants.
To G. agnicellus, its precise relationship to fungi is one of several unknowns, but it will be important to find out. Its habitat under specific trees suggests that the mycorrhizal system on which it is based is quite specific. This is consistent with other species in the genus, but it also means that threats to their habitat, such as invasion of human agriculture and forest fires, could be a serious problem.
It is also unclear how the plant is pollinated. Ants were observed crawling in and out of the flowers (probably, Hermans pointed out, to steal nectar), so this is a possible route of pollination. But more study will be needed to determine how G. agnicellus it is based on and contributes to the complex ecosystem it inhabits.
But there is good news. Although the extent of the plant appears small, it has been found in the protected area of Ranomafana National Park. Which means, according to Kew Gardens, that it has some protection, for now, against anthropogenic habitat loss.
G. agnicellus has been selected as one of the 10 new species in Kew Gardens of 2020 and described in Curtis Botanical Journal.