The abdomen in both sexes is mainly black on top with the exception of (segment) S8 which is blue or, brown in some females. Both sexes have two-toned wing spots (pterostigma) on the front wings, which are whitish towards the tip and twice as long as they are wide.
Apart from the typica form the female occurs in four other colour forms.
The violacea form with violet sides
which will mature into the typica male type colouration or the olive-green thorax with brown S8 of the infuscans form as seen in the mating wheel (or Copula - 'in cop') below.
The rufescens form with orange - pink sides
which will mature into the pale brown colours, with dull brown S8, of the rufescens-obsoleta form.
and seen again 'in cop' in the image below.
These are the most likely Damselflies to be observed 'in cop' as they can typically stay in the mating wheel position for up to six hours....in some of the Dragonfly species, such as the Chasers, it can be as little as a few seconds!
* information taken from the excellent reference book... Britain's Dragonflies by Dave Smallshire and Andy Swash. Published by WildGuides Ltd.