A significant number of dragonfly and damselfly species are recorded. Fishing flies that mimic damselfly nymphs are used in wet-fly fishing. Damselfly nymphs swim by fish-like undulations, the gills functioning like a tail. The general body plan of a damselfly is similar to that of a dragonfly. It has populations of the nationally rare southern damselfly and white-clawed crayfish. Some species of damselfly have elaborate courtship behaviours. Its common names include emerald spreadwing, scarce emerald damselfly and robust spreadwing. The azure damselfly ("Coenagrion puella") is a species of damselfly found in most of Europe. The beautiful demoiselle ("Calopteryx virgo") is a European damselfly belonging to the family Calopterygidae. The distribution and diversity of damselfly species in the biogeographical regions is summarized here. This family has the smallest of damselfly species. The male black-winged damselfly provides a striking example of an adaptation to sperm competition. Lestes silvaticus is a species of spreadwing in the damselfly family Lestidae. The appendages of the large red damselfly can be seen in the gallery below.