Mature males of the Ruby Whiteface have a black body with red and orange markings on the abdomen and thorax which become darker with age.
Young males and females have pale yellow markings.
All have a conspicuous white frons at the front of the head.
The wings have a brown patch at the base.

The Ruby Whiteface (Leucorrhinia rubicunda) can easily be confused with the White-faced Darter (Leucorrhinia dubia).
However, there is one distinctive difference: In Leucorrhinia dubia the edge of the forewing is dark from the base to the middle and yellow from the middle to the tip, whereas in Leucorrhinia rubicunda the edge of the forewing is entirely yellow (from the base to the tip).
In addition, the spots (red with males; yellow with females/young males) on the abdomen of Leucorrhinia dubia are usually smaller than with Leucorrhinia rubicunda.

Bargerveen Nature Reserve, Emmen, The Netherlands, 15 May 2018