ALBERT

Description: Although about two million species have been named, our knowledge about the biodiversity of many taxonomic groups remains inadequate and incomplete. There has been increased taxonomic effort for the discovery of more species and their geographical distribution information. During this process, species collected only from a single specimen/locality often appear. However, there are very few empirical data available to understand the current situation of single specimen/locality species in insect taxonomy. In this paper, we collected 1261 articles containing 4811 insect species from ZooKeys between 2009 and 2017, and we extracted data, including the publication date, number of specimens/locality, and DNA usage. Our analyses demonstrated that 21.53% and 21.74% of new species were described from only one specimen and one locality, respectively, and approximately half of all new species were published based on fewer than five specimens. Meanwhile, the rate of single-specimen species in papers with or without DNA data was 15.06% and 23.43%, respectively, which indicates that incorporating DNA data in species descriptions might effectively decrease the occurrence of single-specimen species. We suggest that taxonomists should adopt more beneficial practices, such as increasing specimen diversity, incorporating DNA data, and improving international collaboration, in the description of new species.