Portrait of Acanthocystis turfacea
(Carter,1863), a centroheliozoon with tangentially layered siliceous scales and two types of forked radial siliceous spines (one short, the other long) and radiating axopodia with extrusomes, all visible in this image. Detail of radiating forked siliceous spines of Acanthocystis turfacea
. . From standing fresh water near Boise, Idaho.DIC.