The UK is home to four resident Darters (Sympetrum), two of which, the Common Darter (Sympetrum striolatum) and Ruddy Darter (Sympetrum sanguineum), are relatively widespread, while the remaining two are more restricted in their distribution. With both males and females to document, I’ve created two separate charts, one for each sex.
The females are all quite similar and can cause confusion. Here is my attempt to clarify them.
[On smaller screens reading may prove difficult so click on the image to open a larger version.]