Societal Impact StatementGiven the current unprecedented concerns for global biodiversity loss, it is critical to identify best practices for describing new species more efficiently so we can complete the inventory of the Neotropical flora and implement appropriate conservation strategies in a timely manner. This study aims to answer the question of how long it takes to describe a new species of tree in the Neotropics by calculating the time elapsed from collection of the first specimen to the publication of a new species. It demonstrates that enhancing international collaboration and promoting taxonomy training may be the most efficient ways to accelerate species descriptions.Summary One of the main aspects of taxonomic research is the description of new species. Identifying how to describe new species more efficiently is key to completing the inventory of the Neotropical flora in an era of massive biodiversity loss. Here, we calculate the interval between first specimen collection and publication of new species for a group of 2123 Neotropical trees, and discuss the historical context surrounding specimen collection and new species publication events. Our results reveal that on average, it takes almost 16 years from specimen collection to publication of a new Neotropical tree species, which is considerably shorter than previous estimates for other tropical groups. Peru had the longest average time lags by country, while Haiti had the shortest. The average time lags increased until the early 1900s, when a decrease was observed, with the shortest lags between 1941 and 1960. We found that the majority of the species described more rapidly are from plants collected by a field botanist and described by a herbarium‐based researcher as part of ad hoc collaboration, and the ones collected and described by the same researcher. We demonstrate how political instability and conflict can delay or impede the completion of taxonomic research initiatives in the region. We argue that enhancing international collaboration and training opportunities in Latin American countries, as well as ensuring safe plant collection campaigns, are critical to complete the inventory of the Neotropical flora.