Cylindrospermopsis raciborskii was the second N2-fixing filamentous cyanobacterium that invaded Lake Kinneret. It was first observed in 2000 and by 2005 has replaced A. ovalisporum as the dominant N2 fixer in summer-fall. The thin (1.5 - 3 um), delicate filaments of this species are characterized by drop-shaped heterocytes, and when they don\'t appear, pointed terminal cells. In summer 2005 this species formed a massive bloom with > 30,000 filaments/mL.
aalster and tzohary
A Alster & T Zohary, Kinneret Limnological Laboratory, IOLR
Photo taken with an Olympus BX50 Microscope equipped with DIC optics and PixeLink digital camera, mag. X40