A new study revealed that there have been 11,676 Amazonian tree species discovered in the Amazon rainforest between 1707 and 2015, still a little too far away from the 2013 estimation that round up the total number of trees species in the Amazon around 16,000. This means that there are still about 4,000 Amazon tree species still waiting to be discovered.

"Since 1900, between fifty and two hundred new trees have been discovered in the Amazon every year," explained Nigel Pitman, The Field Museum's Mellon Senior Conservation Ecologist, in a statement. "Our analysis suggests that we won't be done discovering new tree species there for three more centuries."

For the study, the researchers tallied up the number of species in more than half a million museum specimens collected from the Amazon between 1707 and 2015. Their tally revealed that 11,676 tree species in the Amazon has already been discovered and described.

In 2013, the same group of researchers estimated a total of 16,000 tree species living in the Amazon. However, no one actually counted the tress specie one by one. Comparing the 2013 estimate and the present tally, researchers believe that there are still around 4,000 of the rarest Amazon tree species hiding in the forest, waiting to be discovered.

The study, published in the journal Scientific Reports, relied upon the digitization of museum collections data--photographs and digital records of the specimens housed in museum collections that are shared worldwide through aggregator sites like IDigBio.

Researchers believe that by having a checklist of all the discovered tree species in the Amazon can provide valuable information to other researchers and can also strengthen conservation efforts.

"We're trying to give people tools so they're not just laboring in the dark," explained Hans ter Steege at the Naturalis Biodiversity Center, in a press release. "The checklist gives scientists a better sense of what's actually growing in the Amazon Basin, and that helps conservation efforts."