Missouri Botanical Garden scientists describe

Scientists and collaborators at the Missouri Botanical Garden have discovered and described a new species of orchid in Central Madagascar with a record nectar spur and close ties to the famous “Darwin’s orchid.” This new species needs urgent conservation action, say scientists.

“The discovery of a new species of orchid is always an exciting event, but finding such amazing and charismatic species happens only once in a scientist’s career. I really hope that this highly threatened species draws attention to the urgent crisis that affects Madagascar’s biodiversity and helps support the Garden’s program here,” said Tariq Stévart, Director of the Garden’s Africa and Madagascar program.

The flora of Madagascar is known for flowers with elongated floral tubes pollinated by long-tongued hawks. The most famous of these species, Angraecum sesquipedale, is known as Darwin’s orchid, to pay tribute to Charles Darwin’s theory that the flower was pollinated on an undiscovered moth with a long proboscis. Scientists have described the large hawkmoth, Xanthopan praedicta, 41 years after its prediction.

A newly published paper, “A new species of orchid expands Darwin’s predicted pollination guild in Madagascar,” reveals an unexpected new case of parallel evolution with Darwin’s orchid in the newly described giant spurge soleangis impraedicta, which the nectar spur reaches 33 cm in length.

“The contrast between the small 2 cm flowers and the hyper-long nectar tube is amazing,” said co-author João Farminhão of the Botanical Garden of the University of Coimbra.

Solenangis impraedicta has the third longest spur ever recorded among flowering plants, and the longest nectar spur of any known plant relative to flower size. It is the only new orchid species with such extreme adaptation to hawkmoth pollination described since 1965.

Patrice Antilahimena, a field botanist at the Garden, first collected the species during the baseline environmental impact study of a mining site in Central-Eastern Madagascar. Ten years later, Garden Botany Brigitte Ramandimbisoa and Simon Verlynde, student of Ph.D. in the New York Botanical Garden, they discovered a new place. The novelty belongs to the group of angraecoid orchids that Stévart and an international team of experts have studied extensively. Stévart, an expert in African orchid taxonomy and conservation, first identified this species as an undescribed species of Solenangis.

This sensational new member of the ‘Darwin Pollination Guild’ is threatened by mining and potentially poaching for the orchid trade.

“A precautionary approach is necessary when publishing such a spectacular new species. Wild populations must be protected and monitored and detailed information about their precise coordinates must be kept out of the public domain. Therefore, please do not ask us to reveal where we found it, somewhere in Madagascar,” Stévart added.

The gap of 15 years between the discovery of this species and the formal description allowed the team to implement conservation measures before the Solenangis, stripped of the giant, achieved fame. These include ex situ culture and the seed bank as part of a collaboration between the Garden and the Ambatovy Conservation Department.

The pollination biology of Solenangis impraedicta was studied using camera traps by Marie Savignac in 2019.

The observation period did not result in any conclusive pollination events, but the most likely pollinators are the large coelonia solani and Xanthopan praedicta. The name of the species “impraedicta” (meaning unexpected in Latin) is a nod to Darwin’s prediction of the star orchid pollinator, which took 130 years to fully confirm. Hopefully this time it won’t take so long to identify the pollinator in the act.

Photos and illustrations can be found here: Solenangis impraedicta images.

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The mission of the Missouri Botanical Garden is “to discover and share knowledge of plants and their environment to preserve and enrich life.” Today, 165 years after opening, the Missouri Botanical Garden is a National Historic Landmark and a center for science, conservation, education and horticultural display.