Acceleration of new species discoveries is fundamental to global biodiversity conservation. Species attributes have been widely considered as strong predictors for species discoveries, as species with larger geographic range and body size tend to be described earlier. Previous studies mainly focused on models including all known species. However, it remains unclear whether species attributes can still be used to predict more recent species discoveries, and to guide future species discoveries. Here, we compiled data of description date, biological traits and environmental information where species occur for 632 mammal species in China. We explored the temporal changes of predictive strength of species attributes in predicting species description dates over a 254-year period. We showed that when considering all known species, species attributes, especially the number of congenerics and mean elevation within species distribution range, have contributed 63.73% of the total variation in description date. When only recently described species were considered, however, the predictive strength of species attributes decreased. For species described in the recent century, most species attributes became not important in predicting species description dates. Our results suggest that more recently discovered species tend to share similar species attributes, indicating that species attributes will be weak predictors for future species discovery. To accelerate species discoveries and make catalog of life as complete as possible, our study highlights an urgent need to conduct specific biodiversity surveys with traditional taxonomic methods based on distinctive species attributes, and molecular phylogeny-based taxonomy to discover new species from taxonomically complex groups.
