A 'Blood Rain' Infiltrates Villages of Spain (2 of 3) (image) FECYT - Spanish Foundation for Science and Technology Share Print E-Mail Caption This is a colony of microalgae 'H. pluvialis' in a state of encystment and a close-up of the red color of the cell's nucleus due to the production of astaxanthin. The arrow points to a transparent specimen that does not possess the carotenoid. Credit J. Fernández-Lozano et al. / USAL Usage Restrictions None 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.