Calopteryx virgo Mating (image) Lund University Share Print E-Mail Caption Male and female of the beautiful demoiselle (Calopteryx virgo) in the so-called "mating wheel." Note the male's dark blue wings, while the female is brown. Credit Photo: Erik Svensson / Lund University Usage Restrictions Photo: Erik Svensson / Lund University Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.