Figure 5.

Cryo-transmission electron microscopy (TEM) images of planktonic cells recovered from lake water on the 0.1-μm filters confirm the presence of very small cells, likely members of the Nanohaloarchaea. In all images, the electron microscopy grid is evident in the background. (a) Cryo-TEM of an organism presumed to be a nanohaloarchaeon next to a larger putative Haloquadratum-like organism. (b) An organism presumed to be a member of the Nanohaloarchaea because of its small size and small contrast elements in the inner membrane, outer membrane and perisplasmic space, as have been seen in the ARMAN nanoarchaea (Comolli and Banfield, 2014).