Botanical Garden researchers discover rare tree in Rio

A new species of fruit tree has been found in the area of the Pedra de Itaocaia Municipal Natural Monument, in the municipality of Maricá, in the metropolitan region of Rio de Janeiro. The discovery of Siphoneugena carolynae, a “close relative” of the jabuticaba trees, was made by Rio de Janeiro Botanical Garden researchers Thiago Fernandes and João Marcelo Braga.

The study reveals that this 7-meter-tall tree is unique in the world. According to researcher Thiago Fernandes, only one specimen of the species has been identified so far.

“It’s the 13th species of the Siphoneugena genus known so far. We collected it while the fruit was still green, so we haven’t seen the ripe fruit yet. However, we expect it to be similar to jabuticabas (Plinia genus), given their close relationship,” states the Botanical Garden study.

Thiago Fernandes noted that the region has attracted the interest of naturalists since the 19th century, including Charles Darwin. The British naturalist, geologist, and biologist visited the area in 1832 and stayed at the historic Fazenda Itaocaia, the very site where the species was discovered.

The researcher sees this as a significant breakthrough for science. “This discovery advances our understanding of the Atlantic Forest's flora, which still harbors many species unknown to science. It also demonstrates the importance of protected areas in conserving this and other rare species with limited distribution,” he added.

Siphoneugena Carolynae - Thiago Fernandes/JB

Thiago Fernandes noted that he has been conducting studies with his supervisor and other collaborators since his graduation, and this is not the first rare discovery they have made.

"We’ve made additional discoveries in the area, including a fruit species previously known from just one 19th-century collection, now being cultivated at the Botanical Garden. We also identified two new species in Itaocaia and Niterói,” he said.

According to the Botanical Garden, the scientific name of the new tree was proposed by the researchers to honor Carolyn E. B. Proença, a senior specialist in Myrtaceae from the University of Brasília. This plant family, prevalent in the Americas, includes fruit trees such as guava and jabuticaba. The name recognizes Proença’s extensive career in advancing the taxonomy and reproductive biology of Myrtaceae species, as well as her contributions to the discussion on this new species.

“The results of the research were published last July in the scientific journal Brittonia, a publication of the New York Botanical Garden, one of the most respected in the world,” said the Botanical Garden.