WIP is short for Wing Interference Pattern, and is a newly discovered morphological character system present in extremely thin insect wings, i.e. in wings of very small insect species (pdf of pub.). Seemingly clear and non-pigmented wings display WIPs if viewed against a dark background. Many small Hymenoptera have colourful WIPs and a number of Eulophidae species show strikingly beautiful colour patterns. The significance of these patterns remains to be discovered, but in some genera they appear to be species specific and in some groups they appear to be genus specific. To see a selection of WIPs of the Eulophidae click here, and to see a more extensive photo gallery click here. In the latter photo gallery the images are arranged alphabetically by genus, and within genera alphabetically by species. More examples from other chalcid groups are posted on this website wipbarcode.
To get good pictures, or a good view of WIPs the wings are removed from the specimen and placed on a slide. To keep the wings flat a thin cover glass is placed on top of them. The slide is then viewed against a black background, and the colour pattern appears as if by magic. After the wings have been photographed (if that is an option) the wings are glued to the card with the specimens from which they were removed.