Soprano pipistrelle (IMAGE) University of Oldenburg Caption The soprano pipistrelle (Pipistrellus pygmaeus) weighs no more than a quarter dollar. Tens of thousands of individuals fly south along the Baltic coast of Latvia in August and September. Credit Christian Giese Usage Restrictions Use only in connection with press release and with appropriate credit. License Licensed content 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.