WIP stands for “wing interference pattern” and it refers to the shiny patterns of light refracted from the wings of insects (for example, little parasitoid wasps). These patterns are ubiquitous and there is some excitement in the notion that they might eventually be usable for identification purposes.
If so, there could be huge benefits. For example, you could identify damaged specimens with only the wings intact, or you could identify wings that had become removed from specimens. At the very least, it could provide confirmation of an identification.
Anyway, WIPs are very interesting to look at as well, so I thought I would share some. These are all photos borrowed from the USGS flickr feed, by Sam Droege.
If you have some pinned specimens, try and look for WIPs…according to Sam Droege, “Best viewing if WIPs is to have the light source from above and a black background behind.“