3,026 plants in one park — Brazil's greenest treasure chest, fully counted

Deep in Rio de Janeiro's mountains, botanists have finished one of the most exhaustive plant inventories ever undertaken in Brazil. Serra dos Órgãos National Park now holds the richest documented flora of any protected area in the country: 3,026 species — 2,342 flowering plants, 433 ferns, 250 bryophytes — packed into just under 20,000 hectares of Atlantic Forest. That is roughly 38% of all plant species known in the entire state of Rio de Janeiro, squeezed into about half a percent of its territory, and 26.7% more than the previous tally. Botanist Marcus A. Nadruz Coelho of the Rio de Janeiro Botanical Garden and Cecília Cronemberger of the Chico Mendes Institute compiled the list from years of fieldwork plus two centuries of herbarium records reaching back to the 1820s. Published in the journal Discover Conservation, the inventory found 28 species that grow nowhere else on Earth, and 103 classified as threatened.