The legume family has grown - ten new species and two genera discovered

A team formed by Brazilian researchers, including the Botanical Garden of Rio de Janeiro, and foreigners discovered ten new species of leguminous plants native to Brazil, Bolivia, Peru, and Venezuela, many with strong indications of threat of extinction. One of them is the barbatimão-do-rio-doce (Stryphnodendron flavotomentosum), a tree that can reach 20 meters in height and, until now, has been found only in the Atlantic Forest of the Rio Doce basin, in Espírito Santo. The genus Stryphnodendron is best known for the medicinal plant barbatimão (Stryphnodendron astringens), a species native to the Cerrado.  The leguminous trees produce fruits and grains, such as, for example, the pod.

Another case that draws attention is Stryphnodendron velutinum, a tree species up to five meters tall, endemic to a small area of cerradão - a Cerrado forest formation - located in the northwest of Minas Gerais. The species occurs outside conservation units in a landscape heavily impacted by human activity.

- We analyzed a large number of specimens deposited in herbaria, including that of the Rio de Janeiro Botanical Garden, and carried out expeditions in search of barbatimão species. This allowed us to know them better, besides describing new species to the science - says Alexandre Gibau de Lima, PhD student at the National School of Tropical Botany/JBRJ and one of the authors of the studies.

According to him, the research described two new genera (scientific classification that groups a set of species) for science, named Naiadendron and Gwilymia. The name Naiadendron is a combination of naiades (nymphs of fresh waters, rivers and lakes in Greek mythology) and dendron (tree in Greek), that is, the tree of naiades. The name was chosen as a way to honor the Amazon forest and the German botanist Carl Friedrich Philipp von Martius, who, in his work, symbolically represented the Brazilian Amazon with the figure of the naiades.

The name Gwilymia is a tribute to the botanist Gwilym Peter Lewis, a researcher at the Royal Gardens of Kew in the UK, for his great contribution to legume studies.

The genus Stryphnodendron Mart. (legumes) comprises species unique to the Neotropics, many of them native to the Amazon and Cerrado. The species range from small shrubs to giant trees over 40 meters high.

- In contrast to Stryphnodendron astringens, established as a medicinal plant, many of the other species of the genus were poorly known and showed strong indications of being threatened with extinction. In this sense, our studies are essential, since they provide robust data to support conservation actions and studies on the biotechnological potential of the species - concluded Vidal de Freitas Mansano, researcher at the Rio Botanical Garden and also one of the authors of the studies.

The group also includes researchers from the University of São Paulo (USP), Empresa Brasileira de Pesquisa Agropecuária (Embrapa), Universidade Federal de Ouro Preto (UFOP), Universidade Federal de Santa Catarina (UFSC), Universidade Federal de São Carlos (UFSCAR), Universidade Estadual de Feira de Santana (UEFS), University of Gothenburg (GU), in Sweden, and the University of Zurich (UZH), in Switzerland.

The new species were described and published in the journals Systematic Botany and Phytotaxa. The new genera were published in PhytoKeys, in the 14th edition of Advances in Legume Systematics, a special issue coordinated by the international community of legume specialists to publish and promote the most recent and significant advances in the evolutionary and taxonomic knowledge of this plant family.

The articles can be found in the following links:

Lima, A.G.; Paula-Souza, J.; Scalon, V.R. and Souza, V. C. 2021. Stryphnodendron flavotomentosum (Leguminosae, Caesalpinioideae, mimosoid clade), a New Species from the Atlantic Forest, Brazil. Systematic Botany.

Lima, A.G.; Paula-Souza, J.; Ringelberg, J.; Simon, M.F.; Queiroz, L.P.; Borges, L. M.; Mansano, V.F.; Souza, V.C. and Scalon, V.R. New Segregates from the Neotropical Genus Stryphnodendron (Leguminosae, Caesalpinioideae, mimosoid clade). Phytokeys.

Scalon, V. R.; Paula-Souza, J.P.; Lima, A.G. and Souza, V.C. 2022. A synopsis of the genus Stryphnodendron (Fabaceae, Caesalpinioideae, mimosoid clade). Phytotaxa.