Male Calopteryx virgo (image) Lund University Share Print E-Mail Caption This is the male of the greater demoiselle (Calopteryx virgo). The dark blue wings are present only in the males; the females do not have them. 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.