The World Neuropterida Metakey is an integrating resource that contains web site and database elements. Both classes of elements are updated episodically. Significant one-time or cumulative updates are treated as ‘versions’ and are numbered and documented in Table 1. Minor updates between versions are treated as ‘releases’ and only the active release is documented in Table 1. The states of selected web pages as they existed at the time of the initial release of each version are documented as page snapshots in Table 2.