The four-spotted chaser (Libellula quadrimaculata), known in North America as the four-spotted skimmer, is a dragonfly of the family Libellulidae found frequently throughout Europe, Asia, and North America.
The adult stage is found between April to early September in the United Kingdom, and from mid-May to mid-August in Ireland. Larvae have a two-year developmental cycle. Adults feed predominantly on mosquitoes, gnats and midges; the larvae feed primarily on other aquatic insect larvae and on tadpoles.
There is a variant form, praenubila Newman, which has exaggerated wing spots. This is believed to be related to water temperatures during larval development, and appears to be more common in Europe than in the Americas.