Definition

A category on the IUCN Red List of Threatened Species which indicates there is inadequate information to make a direct, or indirect, assessment of a taxon's risk of extinction based on its distribution and/or population status. A taxon in this category may be well studied, and its biology well known, but appropriate data on abundance and/or distribution are lacking.

International Union for Conservation of Nature (IUCN) 2012 ¹