Library of Identification Resources: a FAIR overview of taxonomic keys.

Biodiversity is declining globally, and ecological research is key to monitor and counteract this decline. Such research requires the taxonomic identification of organisms by both professional and citizen scientists. A complete overview of resources for taxonomic identification is therefore crucial but missing, also posing problems for analysis into gaps in the taxonomic coverage of available identification resources. To create a repository of this kind, we applied the FAIR principles, collected data on identification resources, and created a search engine to find relevant identification resources for a given observation of an organism within this data. So far, the data collection has been strongly biased towards keys for insects of Northwestern Europe, leading to incomplete search results for other, underrepresented taxa and regions, which is then indicated in the interface. Our Library of Identification Resources already contains 2,158 works and is made available as linked data using domain-standard vocabularies including BIBO and Audiovisual Core. To increase the accuracy, size and scope of the repository, processes for entering metadata of identification resources should be streamlined. We discuss how publishers, authors, and libraries could be involved and persuaded to register their own published dichotomous or multi-access keys, species descriptions, field guides, and image- or audio-based identification applications, as inclusion makes their identification resources findable for a larger group of potential users.