Several mature males within the Libellulids develop a powdery blue coating called pruinosity (after the bloom that develops on some prunes); it is actually a waxy deposit. We can’t help referring to these characters as “prunes”.
In Europe there are six such potentially confusing species but in the UK we are limited to these four, two of which are Chasers and two of which are Skimmers:
- Scarce Chaser (Libellula fulva)
- Broad-bodied Chaser (Libellula depressa)
- Keeled Skimmer (Orthetrum coerulescens)
- Black-tailed Skimemr (Orthetrum cancellatum)
[In case this diagram proves difficult to read, clicking on it will open a larger version.]